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Essays on Endangered Species

Endangered species essay topics and outline examples, essay title 1: vanishing wonders: the plight of endangered species and conservation efforts.

Thesis Statement: This essay explores the critical issue of endangered species, delving into the causes of endangerment, the ecological significance of these species, and the conservation strategies aimed at preserving them for future generations.

• Introduction
• Understanding Endangered Species: Definitions and Criteria
• Causes of Endangerment: Habitat Loss, Climate Change, Poaching, and Pollution
• Ecological Significance: The Role of Endangered Species in Ecosystems
• Conservation Strategies: Protected Areas, Breeding Programs, and Legal Protections
• Success Stories: Examples of Species Recovery and Reintroduction
• Ongoing Challenges: Balancing Conservation with Human Needs
• Conclusion: The Urgent Need for Global Action in Protecting Endangered Species

Essay Title 2: Beyond the Numbers: The Ethical and Moral Imperatives of Endangered Species Preservation

Thesis Statement: This essay examines the ethical dimensions of endangered species preservation, addressing questions of human responsibility, intrinsic value, and the moral imperative to protect and restore these species.

• The Ethical Dilemma: Balancing Human Needs and Species Preservation
• Intrinsic Value: Recognizing the Inherent Worth of All Species
• Interconnectedness: Understanding the Ripple Effects of Species Loss
• Human Responsibility: The Moral Imperative to Protect Endangered Species
• Conservation Ethics: Ethical Frameworks and Philosophical Perspectives
• Legislation and International Agreements: Legal Approaches to Ethical Conservation
• Conclusion: Embracing Our Role as Stewards of Biodiversity

Essay Title 3: The Economic Value of Biodiversity: Endangered Species and Sustainable Development

Thesis Statement: This essay explores the economic aspects of endangered species conservation, highlighting the potential economic benefits of preserving biodiversity, sustainable ecotourism, and the long-term economic consequences of species loss.

• Economic Importance of Biodiversity: Ecosystem Services and Human Well-being
• Sustainable Ecotourism: How Endangered Species Can Drive Local Economies
• Case Studies: Success Stories of Economic Benefits from Species Conservation
• The Costs of Inaction: Economic Consequences of Species Extinction
• Corporate Responsibility: Businesses and Conservation Partnerships
• Balancing Economic Growth with Conservation: The Path to Sustainable Development
• Conclusion: The Interplay Between Biodiversity, Economics, and a Sustainable Future

Giant Pandas Ailuropoda

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Endangered Species: The African Elephant

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Endangered Species in Vietnam: South China Tiger and Asian Elephant

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De-extinction Can Help to Protect Endangered Species

Protection of endangered species can help us to survive, the way zoos helps to protect endangered species, ways of protection endangered species, sharks demand protection just like endangered species, the reasons why the koala species is endangered, the issue of philippine eagle endangerment, the issue of conserving endangered animals in the jungles of southeast asia, primates research project: the bushmeat crisis, the negative impact of the food culture on the environment and jani actman article that fish on your dinner plate may be an endangered species, nesting and population ecology of western chimpanzee in bia conservation area, human impact on red panda populations , the impact of climate change on the antarctic region, the ethics of bengal tigers, poaching and the illegal trade.

Endangered species are living organisms that face a high risk of extinction in the near future. They are characterized by dwindling population numbers and a significant decline in their natural habitats. These species are vulnerable to various factors, including habitat destruction, pollution, climate change, overexploitation, and invasive species, which disrupt their ecological balance and threaten their survival.

The early stages of human civilization witnessed a relatively harmonious coexistence with the natural world. Indigenous cultures across the globe held deep reverence for the interconnectedness of all living beings, fostering a sense of stewardship and respect for the environment. Nevertheless, with the rise of industrialization and modernization, the exploitation of natural resources escalated at an unprecedented pace. The late 19th and early 20th centuries marked a turning point, as rapid urbanization, deforestation, pollution, and overhunting posed significant threats to numerous species. The dawn of globalization further accelerated these challenges, as international trade in exotic species intensified and habitats faced relentless encroachment. In response to this growing concern, conservation movements emerged worldwide. Influential figures such as John Muir, Rachel Carson, and Aldo Leopold championed the cause of environmental preservation, raising awareness about the fragility of ecosystems and the need for proactive measures. International conventions and treaties, such as the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), were established to regulate and monitor the trade of endangered species across borders. As our understanding of ecological dynamics deepened, scientific advancements and conservation efforts gained momentum. Endangered species recovery programs, habitat restoration initiatives, and the establishment of protected areas have all played a vital role in safeguarding vulnerable populations. However, the struggle to protect endangered species continues in the face of ongoing challenges. Climate change, habitat destruction, poaching, and illegal wildlife trade persist as formidable threats. Efforts to conserve endangered species require a multi-faceted approach, encompassing scientific research, policy development, sustainable practices, and international collaboration.

Leonardo DiCaprio: An acclaimed actor and environmental activist, DiCaprio has been an outspoken advocate for wildlife conservation. Through the Leonardo DiCaprio Foundation, he has supported various initiatives aimed at protecting endangered species and their habitats. Sigourney Weaver: Besides her notable acting career, Sigourney Weaver has been a passionate environmental activist. She has advocated for the protection of endangered species, particularly in her role as an honorary co-chair of the Dian Fossey Gorilla Fund. Prince William: The Duke of Cambridge, Prince William, has shown a deep commitment to wildlife conservation. He has actively supported initiatives such as United for Wildlife, which aims to combat the illegal wildlife trade and protect endangered species. Edward Norton: Actor and environmental activist Edward Norton has been actively involved in various conservation efforts. He co-founded the Conservation International's Marine Program and has been vocal about the need to protect endangered species and their habitats.

Amur Leopard (Panthera pardus orientalis) Sumatran Orangutan (Pongo abelii) Javan Rhino (Rhinoceros sondaicus) Vaquita (Phocoena sinus) Cross River Gorilla (Gorilla gorilla diehli) Hawksbill Turtle (Eretmochelys imbricata) Yangtze River Dolphin (Lipotes vexillifer) Philippine Eagle (Pithecophaga jefferyi) Sumatran Tiger (Panthera tigris sumatrae) African Elephant (Loxodonta africana)

1. Habitat Loss and Fragmentation 2. Climate Change 3. Pollution 4. Overexploitation and Illegal Wildlife Trade 5. Invasive Species 6. Disease and Pathogens 7. Lack of Conservation Efforts and Awareness 8. Genetic Issues 9. Natural Factors

The majority of the public recognizes the significance of conserving endangered species. Many people believe that it is our moral obligation to protect and preserve the Earth's diverse wildlife. They understand that losing species not only disrupts ecosystems but also deprives future generations of the natural beauty and ecological services they provide. Some individuals view endangered species conservation through an economic lens. They understand that wildlife and ecosystems contribute to tourism, provide ecosystem services like clean water and air, and support local economies. These economic arguments often align with conservation efforts, highlighting the potential benefits of protecting endangered species. Additionally, public opinion on endangered species is often shaped by awareness campaigns, education initiatives, and media coverage. Increased access to information about the threats faced by endangered species and the consequences of their decline has resulted in a greater understanding and concern among the public. Many people support the implementation and enforcement of laws and regulations aimed at protecting endangered species. They believe that legal frameworks are essential for ensuring the survival of vulnerable species and holding individuals and industries accountable for actions that harm wildlife. Moreover, individuals increasingly feel a sense of personal responsibility in addressing the issue of endangered species. This includes making conscious choices about consumption, supporting sustainable practices, and engaging in activities that contribute to conservation efforts, such as volunteering or donating to wildlife organizations. Public opinion can vary when it comes to instances where the protection of endangered species conflicts with human interests, such as land use, agriculture, or development projects. These situations can lead to debates and differing perspectives on how to balance conservation needs with other societal needs.

"Silent Spring" by Rachel Carson: Published in 1962, this influential book is credited with launching the modern environmental movement. Carson's seminal work highlighted the devastating impacts of pesticides, including their effects on wildlife and the environment. It drew attention to the need for conservation and sparked widespread concern for endangered species. "Gorillas in the Mist" by Dian Fossey: Fossey's book, published in 1983, chronicled her experiences studying and protecting mountain gorillas in Rwanda. It shed light on the challenges faced by these endangered primates and brought their conservation needs to the forefront of public consciousness. "March of the Penguins" (2005): This acclaimed documentary film depicted the annual journey of emperor penguins in Antarctica. By showcasing the hardships and perils these penguins face, the film garnered widespread attention and empathy for these remarkable creatures, raising awareness about their vulnerability and the impacts of climate change. "The Cove" (2009): This documentary exposed the brutal practice of dolphin hunting in Taiji, Japan. It not only brought attention to the mistreatment of dolphins but also highlighted the interconnectedness of species and the urgent need for their protection. "Racing Extinction" (2015): This documentary film by the Oceanic Preservation Society addressed the issue of mass species extinction and the human-driven factors contributing to it. It aimed to inspire viewers to take action and make positive changes to protect endangered species and their habitats.

1. It is estimated that around 26,000 species are currently threatened with extinction, according to the International Union for Conservation of Nature (IUCN). 2. The illegal wildlife trade is the fourth largest illegal trade globally, following drugs, counterfeiting, and human trafficking. It is a significant contributor to species endangerment. 3. The World Wildlife Fund (WWF) reports that since 1970, global wildlife populations have declined by an average of 68%. 4. Habitat loss is the primary cause of species endangerment, with deforestation alone accounting for the loss of around 18.7 million acres of forest annually. 5. The poaching crisis has pushed some iconic species to the brink of extinction. For example, it is estimated that only about 3,900 tigers remain in the wild. 6. The Hawaiian Islands are considered the endangered species capital of the world, with more than 500 endangered or threatened species due to habitat loss and invasive species. 7. Coral reefs, one of the most diverse ecosystems on the planet, are under significant threat. It is estimated that 75% of the world's coral reefs are currently threatened, primarily due to climate change, pollution, and overfishing. 8. The illegal pet trade is a significant threat to many species. It is estimated that for every live animal captured for the pet trade, several die during capture or transport. 9. The IUCN Red List, a comprehensive inventory of the conservation status of species, currently includes more than 38,000 species, with approximately 28% of them classified as threatened with extinction.

The topic of endangered species holds immense importance for writing an essay due to several compelling reasons. Firstly, endangered species represent a vital component of the Earth's biodiversity, playing crucial roles in maintaining ecosystem balance and functioning. Exploring this topic allows us to understand the interconnectedness of species and their habitats, emphasizing the intricate web of life on our planet. Secondly, the issue of endangered species is a direct reflection of human impacts on the environment. It brings attention to the consequences of habitat destruction, climate change, pollution, and unsustainable practices. By studying this topic, we can delve into the root causes of species endangerment and contemplate the ethical and moral dimensions of our responsibility towards other living beings. Moreover, the plight of endangered species evokes strong emotional responses, prompting discussions on the intrinsic value of nature and our duty to conserve it for future generations. Writing about endangered species enables us to raise awareness, foster empathy, and advocate for sustainable practices and conservation initiatives.

1. Dudley, N., & Stolton, S. (Eds.). (2010). Arguments for protected areas: Multiple benefits for conservation and use. Earthscan. 2. Fearn, E., & Butler, C. D. (Eds.). (2019). Routledge handbook of eco-anxiety. Routledge. 3. Groombridge, B., & Jenkins, M. D. (2002). World atlas of biodiversity: Earth's living resources in the 21st century. University of California Press. 4. Hoekstra, J. M., Boucher, T. M., Ricketts, T. H., & Roberts, C. (2005). Confronting a biome crisis: Global disparities of habitat loss and protection. Ecology Letters, 8(1), 23-29. 5. Kiesecker, J. M., & Copeland, H. E. (Eds.). (2018). The biogeography of endangered species: Patterns and applications. Island Press. 6. Laurance, W. F., Sayer, J., & Cassman, K. G. (2014). Agricultural expansion and its impacts on tropical nature. Trends in Ecology & Evolution, 29(2), 107-116. 7. Meffe, G. K., & Carroll, C. R. (Eds.). (1997). Principles of conservation biology. Sinauer Associates. 8. Primack, R. B. (2014). Essentials of conservation biology. Sinauer Associates. 9. Soulé, M. E., & Terborgh, J. (Eds.). (1999). Continental conservation: Scientific foundations of regional reserve networks. Island Press. 10. Wilson, E. O. (2016). Half-earth: Our planet's fight for life. Liveright Publishing.

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Endangered Species

An endangered species is a type of organism that is threatened by extinction. Species become endangered for two main reasons: loss of habitat and loss of genetic variation.

Biology, Ecology, Geography, Conservation

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An endangered species is a type of organism that is threatened by extinction . Species become endangered for two main reasons: loss of habitat and loss of genetic variation . Loss of Habitat A loss of habitat can happen naturally. Nonavian dinosaurs , for instance, lost their habitat about 65 million years ago. The hot, dry climate of the Cretaceous period changed very quickly, most likely because of an asteroid striking Earth. The impact of the asteroid forced debris into the atmosphere , reducing the amount of heat and light that reached Earth’s surface. The dinosaurs were unable to adapt to this new, cooler habitat. Nonavian dinosaurs became endangered, then extinct . Human activity can also contribute to a loss of habitat. Development for housing, industry , and agriculture reduces the habitat of native organisms. This can happen in a number of different ways. Development can eliminate habitat and native species directly. In the Amazon rainforest of South America, developers have cleared hundreds of thousands of acres. To “clear” a piece of land is to remove all trees and vegetation from it. The Amazon rainforest is cleared for cattle ranches , logging , and ur ban use. Development can also endanger species indirectly. Some species, such as fig trees of the rainforest, may provide habitat for other species. As trees are destroyed, species that depend on that tree habitat may also become endangered. Tree crowns provide habitat in the canopy , or top layer, of a rainforest . Plants such as vines, fungi such as mushrooms, and insects such as butterflies live in the rainforest canopy. So do hundreds of species of tropical birds and mammals such as monkeys. As trees are cut down, this habitat is lost. Species have less room to live and reproduce . Loss of habitat may happen as development takes place in a species range . Many animals have a range of hundreds of square kilometers. The mountain lion ( Puma concolor ) of North America, for instance, has a range of up to 1,000 square kilometers (386 square miles). To successfully live and reproduce, a single mountain lion patrols this much territory. Urban areas , such as Los Angeles, California, U.S.A., and Vancouver, British Columbia, Canada, grew rapidly during the 20th century. As these areas expanded into the wilderness, the mountain lion’s habitat became smaller. That means the habitat can support fewer mountain lions. Because enormous parts of the Sierra Nevada, Rocky, and Cascade mountain ranges remain undeveloped, however, mountain lions are not endangered. Loss of habitat can also lead to increased encounters between wild species and people. As development brings people deeper into a species range, they may have more exposure to wild species. Poisonous plants and fungi may grow closer to homes and schools. Wild animals are also spotted more frequently . These animals are simply patrolling their range, but interaction with people can be deadly. Polar bears ( Ursus maritimus ), mountain lions, and alligators are all predators brought into close contact with people as they lose their habitat to homes, farms , and businesses. As people kill these wild animals, through pesticides , accidents such as collisions with cars, or hunting, native species may become endangered.

Loss of Genetic Variation Genetic variation is the diversity found within a species. It’s why human beings may have blond, red, brown, or black hair. Genetic variation allows species to adapt to changes in the environment. Usually, the greater the population of a species, the greater its genetic variation. Inbreeding is reproduction with close family members. Groups of species that have a tendency to inbreed usually have little genetic variation, because no new genetic information is introduced to the group. Disease is much more common, and much more deadly, among inbred groups. Inbred species do not have the genetic variation to develop resistance to the disease. For this reason, fewer offspring of inbred groups survive to maturity. Loss of genetic variation can occur naturally. Cheetahs ( Acinonyx jubatus ) are a threatened species native to Africa and Asia. These big cats have very little genetic variation. Biologists say that during the last Ice Age , cheetahs went through a long period of inbreeding. As a result, there are very few genetic differences between cheetahs. They cannot adapt to changes in the environment as quickly as other animals, and fewer cheetahs survive to maturity. Cheetahs are also much more difficult to breed in captivity than other big cats, such as lions ( Panthera leo ). Human activity can also lead to a loss of genetic variation. Overhunting and overfishing have reduced the populations of many animals. Reduced population means there are fewer breeding pairs . A breeding pair is made up of two mature members of the species that are not closely related and can produce healthy offspring. With fewer breeding pairs, genetic variation shrinks. Monoculture , the agricultural method of growing a single crop , can also reduce genetic variation. Modern agribusiness relies on monocultures. Almost all potatoes cultivated , sold, and consumed, for instance, are from a single species, the Russet Burbank ( Solanum tuberosum ). Potatoes, native to the Andes Mountains of South America, have dozens of natural varieties. The genetic variation of wild potatoes allows them to adapt to climate change and disease. For Russet Burbanks, however, farmers must use fertilizers and pesticides to ensure healthy crops because the plant has almost no genetic variation. Plant breeders often go back to wild varieties to collect genes that will help cultivated plants resist pests and drought, and adapt to climate change. However, climate change is also threatening wild varieties. That means domesticated plants may lose an important source of traits that help them overcome new threats. The Red List The International Union for Conservation of Nature (IUCN) keeps a “Red List of Threatened Species.” The Red List de fines the severity and specific causes of a species’ threat of extinction. The Red List has seven levels of conservation: least concern , near threatened , vulnerable, endangered, critically endangered , extinct in the wild , and extinct. Each category represents a different threat level. Species that are not threatened by extinction are placed within the first two categories—least concern and near-threatened. Those that are most threatened are placed within the next three categories, known as the threatened categories —vulnerable, endangered, and critically endangered. Those species that are extinct in some form are placed within the last two categories—extinct in the wild and extinct. Classifying a species as endangered has to do with its range and habitat, as well as its actual population. For this reason, a species can be of least concern in one area and endangered in another. The gray whale ( Eschrichtius robustus ), for instance, has a healthy population in the eastern Pacific Ocean, along the coast of North and South America. The population in the western Pacific, however, is critically endangered.

Least Concern Least concern is the lowest level of conservation . A species of least concern is one that has a widespread and abundant population. Human beings are a species of least concern, along with most domestic animals , such as dogs ( Canis familiaris ) and cats ( Felis catus ). Many wild animals, such as pigeons and houseflies ( Musca domestica ), are also classified as least concern. Near Threatened A near threatened species is one that is likely to qualify for a threatened category in the near future. Many species of violets , native to tropical jungles in South America and Africa, are near threatened, for instance. They have healthy populations, but their rainforest habitat is disappearing at a fast pace. People are cutting down huge areas of rainforest for development and timber . Many violet species are likely to become threatened. Vulnerable Species The definitions of the three threatened categories (vulnerable, endangered, and critically endangered) are based on five criteria: population reduction rate , geographic range, population size, population restrictions , and probability of extinction . Threatened categories have different thresholds for these criteria. As the population and range of the species decreases, the species becomes more threatened. 1) Population reduction rate A species is classified as vulnerable if its population has declined between 30 and 50 percent. This decline is measured over 10 years or three generations of the species, whichever is longer. A generation is the period of time between the birth of an animal and the time it is able to reproduce. Mice are able to reproduce when they are about one month old. Mouse populations are mostly tracked over 10-year periods. An elephant's generation lasts about 15 years. So, elephant populations are measured over 45-year periods. A species is vulnerable if its population has declined at least 50 percent and the cause of the decline is known. Habitat loss is the leading known cause of population decline. A species is also classified as vulnerable if its population has declined at least 30 percent and the cause of the decline is not known. A new, unknown virus , for example, could kill hundreds or even thousands of individuals before being identified. 2) Geographic range A species is vulnerable if its “ extent of occurrence ” is estimated to be less than 20,000 square kilometers (7,722 square miles). An extent of occurrence is the smallest area that could contain all sites of a species’ population. If all members of a species could survive in a single area, the size of that area is the species’ extent of occurrence. A species is also classified as vulnerable if its “ area of occupancy ” is estimated to be less than 2,000 square kilometers (772 square miles). An area of occupancy is where a specific population of that species resides. This area is often a breeding or nesting site in a species range. 3) Population size Species with fewer than 10,000 mature individuals are vulnerable. The species is also vulnerable if that population declines by at least 10 percent within 10 years or three generations, whichever is longer. 4) Population restrictions Population restriction is a combination of population and area of occupancy. A species is vulnerable if it is restricted to less than 1,000 mature individuals or an area of occupancy of less than 20 square kilometers (8 square miles). 5) Probability of extinction in the wild is at least 10 percent within 100 years. Biologists, anthropologists, meteorologists , and other scientists have developed complex ways to determine a species’ probability of extinction. These formulas calculate the chances a species can survive, without human protection, in the wild. Vulnerable Species: Ethiopian Banana Frog The Ethiopian banana frog ( Afrixalus enseticola ) is a small frog native to high- altitude areas of southern Ethiopia. It is a vulnerable species because its area of occupancy is less than 2,000 square kilometers (772 square miles). The extent and quality of its forest habitat are in decline. Threats to this habitat include forest clearance, mostly for housing and agriculture. Vulnerable Species: Snaggletooth Shark The snaggletooth shark ( Hemipristis elongatus ) is found in the tropical, coastal waters of the Indian and Pacific Oceans. Its area of occupancy is enormous, from Southeast Africa to the Philippines, and from China to Australia. However, the snaggletooth shark is a vulnerable species because of a severe population reduction rate. Its population has fallen more than 10 percent over 10 years. The number of these sharks is declining due to fisheries, especially in the Java Sea and Gulf of Thailand. The snaggletooth shark’s flesh, fins, and liver are considered high-quality foods. They are sold in commercial fish markets, as well as restaurants. Vulnerable Species: Galapagos Kelp Galapagos kelp ( Eisenia galapagensis ) is a type of seaweed only found near the Galapagos Islands in the Pacific Ocean. Galapagos kelp is classified as vulnerable because its population has declined more than 10 percent over 10 years. Climate change is the leading cause of decline among Galapagos kelp. El Niño, the natural weather pattern that brings unusually warm water to the Galapagos, is the leading agent of climate change in this area. Galapagos kelp is a cold-water species and does not adapt quickly to changes in water temperature.

Endangered Species 1) Population reduction rate A species is classified as endangered when its population has declined between 50 and 70 percent. This decline is measured over 10 years or three generations of the species, whichever is longer. A species is classified as endangered when its population has declined at least 70 percent and the cause of the decline is known. A species is also classified as endangered when its population has declined at least 50 percent and the cause of the decline is not known. 2) Geographic range An endangered species’ extent of occurrence is less than 5,000 square kilometers (1,930 square miles). An endangered species’ area of occupancy is less than 500 square kilometers (193 square miles). 3) Population size A species is classified as endangered when there are fewer than 2,500 mature individuals. When a species population declines by at least 20 percent within five years or two generations, it is also classified as endangered. 4) Population restrictions A species is classified as endangered when its population is restricted to less than 250 mature individuals. When a species’ population is this low, its area of occupancy is not considered. 5) Probability of extinction in the wild is at least 20 percent within 20 years or five generations, whichever is longer.

Endangered Species: Scimitar -horned Oryx The scimitar-horned oryx ( Oryx dammah ) is a species of antelope with long horns. Its range extends across northern Africa. Previously, the scimitar-horned oryx was listed as extinct in the wild because the last confirmed sighting of one was in 1988. However, the first group of scimitar-horned oryx was released back into the wild in Chad, in August 2016, and the population is growing. Overhunting and habitat loss, including competition with domestic livestock , are the main reasons for the decline of the oryx’s wild population. Captive herds are now kept in protected areas of Tunisia, Senegal, and Morocco. Scimitar-horned oryxes are also found in many zoos . Critically Endangered Species 1) Population reduction rate A critically endangered species’ population has declined between 80 and 90 percent. This decline is measured over 10 years or three generations of the species, whichever is longer. A species is classified as critically endangered when its population has declined at least 90 percent and the cause of the decline is known. A species is also classified as endangered when its population has declined at least 80 percent and the cause of the decline is not known. 2) Geographic range A critically endangered species’ extent of occurrence is less than 100 square kilometers (39 square miles). A critically endangered species’ area of occupancy is estimated to be less than 10 square kilometers (4 square miles). 3) Population size A species is classified as critically endangered when there are fewer than 250 mature individuals. A species is also classified as critically endangered when the number of mature individuals declines by at least 25 percent within three years or one generation, whichever is longer. 4) Population restrictions A species is classified as critically endangered when its population is restricted to less than 50 mature individuals. When a species’ population is this low, its area of occupancy is not considered. 5) Probability of extinction in the wild is at least 50 percent within 10 years or three generations, whichever is longer. Critically Endangered Species: Bolivian Chinchilla Rat The Bolivian chinchilla rat ( Abrocoma boliviensis ) is a rodent found in a small section of the Santa Cruz region of Bolivia. It is critically endangered because its extent of occurrence is less than 100 square kilometers (39 square miles). The major threat to this species is loss of its cloud forest habitat. People are clearing forests to create cattle pastures .

Critically Endangered Species: Transcaucasian Racerunner The Transcaucasian racerunner ( Eremias pleskei ) is a lizard found on the Armenian Plateau , located in Armenia, Azerbaijan, Iran, and Turkey. The Transcaucasian racerunner is a critically endangered species because of a huge population decline, estimated at more than 80 percent during the past 10 years. Threats to this species include the salination , or increased saltiness, of soil . Fertilizers used for agricultural development seep into the soil, increasing its saltiness. Racerunners live in and among the rocks and soil, and cannot adapt to the increased salt in their food and shelter. The racerunner is also losing habitat as people create trash dumps on their area of occupancy. Critically Endangered Species: White Ferula Mushroom The white ferula mushroom ( Pleurotus nebrodensis ) is a critically endangered species of fungus. The mushroom is critically endangered because its extent of occurrence is less than 100 square kilometers (39 square miles). It is only found in the northern part of the Italian island of Sicily, in the Mediterranean Sea. The leading threats to white ferula mushrooms are loss of habitat and overharvesting. White ferula mushrooms are a gourmet food item. Farmers and amateur mushroom hunters harvest the fungus for food and profit. The mushrooms can be sold for up to $100 per kilogram (2.2 pounds). Extinct in the Wild A species is extinct in the wild when it only survives in cultivation (plants), in captivity (animals), or as a population well outside its established range. A species may be listed as extinct in the wild only after years of surveys have failed to record an individual in its native or expected habitat.

Extinct in the Wild: Monut Kaala Cyanea The Mount Kaala cyanea ( Cyanea superba ) is a large, flowering tree native to the island of Oahu, in the U.S. state of Hawai‘i. The Mount Kaala cyanea has large, broad leaves and fleshy fruit. The tree is extinct in the wild largely because of invasive species. Non-native plants crowded the cyanea out of its habitat, and non-native animals such as pigs, rats, and slugs ate its fruit more quickly than it could reproduce. Mount Kaala cyanea trees survive in tropical nurseries and botanical gardens . Many botanists and conservationists look forward to establishing a new population in the wild. Extinct A species is extinct when there is no reasonable doubt that the last remaining individual of that species has died. Extinct: Cuban Macaw The Cuban macaw ( Ara tricolor ) was a tropical parrot native to Cuba and a small Cuban island, Isla de la Juventud. Hunting and collecting the birds for pets led to the bird’s extinction. The last specimen of the Cuban macaw was collected in 1864. Extinct: Ridley’s Stick Insect Ridley’s stick insect ( Pseudobactricia ridleyi ) was native to the tropical jungle of the island of Singapore. This insect, whose long, segmented body resembled a tree limb, is only known through a single specimen, collected more than 100 years ago. During the 20th century, Singapore experienced rapid development. Almost the entire jungle was cleared, depriving the insect of its habitat.

Endangered Species and People When a species is classified as endangered, governments and international organizations can work to protect it. Laws may limit hunting and destruction of the species’ habitat. Individuals and organizations that break these laws may face huge fines. Because of such actions, many species have recovered from their endangered status. The brown pelican ( Pelecanus occidentalis ) was taken off the endangered species list in 2009, for instance. This seabird is native to the coasts of North America and South America, as well as the islands of the Caribbean Sea. It is the state bird of the U.S. state of Louisiana. In 1970, the number of brown pelicans in the wild was estimated at 10,000. The bird was classified as vulnerable. During the 1970s and 1980s, governments and conservation groups worked to help the brown pelican recover. Young chicks were reared in hatching sites, then released into the wild. Human access to nesting sites was severely restricted. The pesticide DDT , which damaged the eggs of the brown pelican, was banned. During the 1980s, the number of brown pelicans soared. In 1988, the IUCN “delisted” the brown pelican. The bird, whose population is now in the hundreds of thousands, is now in the category of least concern.

Convention on Biological Diversity The Convention on Biological Diversity is an international treaty to sustain and protect the diversity of life on Earth. This includes conservation, sustainability, and sharing the benefits of genetic research and resources. The Convention on Biological Diversity has adopted the IUCN Red List of endangered species in order to monitor and research species' population and habitats. Three nations have not ratified the Convention on Biological Diversity: Andorra, the Holy See (Vatican), and the United States.

Lonesome George Lonesome George was the only living member of the Pinta Island tortoise ( Chelonoidis abingdoni ) known to exist. The Pinta Island tortoise was only found on Pinta, one of the Galapagos Islands. The Charles Darwin Research Station, a scientific facility in the Galapagos, offered a $10,000 reward to any zoo or individual for locating a single Pinta Island tortoise female. On June 25, 2012, Lonesome George died, leaving one more extinct species in the world.

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November 1, 2023

20 min read

Can We Save Every Species from Extinction?

The Endangered Species Act requires that every U.S. plant and animal be saved from extinction, but after 50 years, we have to do much more to prevent a biodiversity crisis

By Robert Kunzig

Snail Darter Percina tanasi. Listed as Endangered: 1975. Status: Delisted in 2022.

© Joel Sartore/National Geographic Photo Ark

A Bald Eagle disappeared into the trees on the far bank of the Tennessee River just as the two researchers at the bow of our modest motorboat began hauling in the trawl net. Eagles have rebounded so well that it's unusual not to see one here these days, Warren Stiles of the U.S. Fish and Wildlife Service told me as the net got closer. On an almost cloudless spring morning in the 50th year of the Endangered Species Act, only a third of a mile downstream from the Tennessee Valley Authority's big Nickajack Dam, we were searching for one of the ESA's more notorious beneficiaries: the Snail Darter. A few months earlier Stiles and the FWS had decided that, like the Bald Eagle, the little fish no longer belonged on the ESA's endangered species list. We were hoping to catch the first nonendangered specimen.

Dave Matthews, a TVA biologist, helped Stiles empty the trawl. Bits of wood and rock spilled onto the deck, along with a Common Logperch maybe six inches long. So did an even smaller fish; a hair over two inches, it had alternating vertical bands of dark and light brown, each flecked with the other color, a pattern that would have made it hard to see against the gravelly river bottom. It was a Snail Darter in its second year, Matthews said, not yet full-grown.

Everybody loves a Bald Eagle. There is much less consensus about the Snail Darter. Yet it epitomizes the main controversy still swirling around the ESA, signed into law on December 28, 1973, by President Richard Nixon: Can we save all the obscure species of this world, and should we even try, if they get in the way of human imperatives? The TVA didn't think so in the 1970s, when the plight of the Snail Darter—an early entry on the endangered species list—temporarily stopped the agency from completing a huge dam. When the U.S. attorney general argued the TVA's case before the Supreme Court with the aim of sidestepping the law, he waved a jar that held a dead, preserved Snail Darter in front of the nine judges in black robes, seeking to convey its insignificance.

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Now I was looking at a living specimen. It darted around the bottom of a white bucket, bonking its nose against the side and delicately fluttering the translucent fins that swept back toward its tail.

“It's kind of cute,” I said.

Matthews laughed and slapped me on the shoulder. “I like this guy!” he said. “Most people are like, ‘Really? That's it?’ ” He took a picture of the fish and clipped a sliver off its tail fin for DNA analysis but left it otherwise unharmed. Then he had me pour it back into the river. The next trawl, a few miles downstream, brought up seven more specimens.

In the late 1970s the Snail Darter seemed confined to a single stretch of a single tributary of the Tennessee River, the Little Tennessee, and to be doomed by the TVA's ill-considered Tellico Dam, which was being built on the tributary. The first step on its twisting path to recovery came in 1978, when the U.S. Supreme Court ruled, surprisingly, that the ESA gave the darter priority even over an almost finished dam. “It was when the government stood up and said, ‘Every species matters, and we meant it when we said we're going to protect every species under the Endangered Species Act,’” says Tierra Curry, a senior scientist at the Center for Biological Diversity.

Bald Eagle Haliaeetus leucocephalus. Listed as Endangered: 1967. Status: Delisted in 2007. Credit: © Joel Sartore/National Geographic Photo Ark

Today the Snail Darter can be found along 400 miles of the river's main stem and multiple tributaries. ESA enforcement has saved dozens of other species from extinction. Bald Eagles, American Alligators and Peregrine Falcons are just a few of the roughly 60 species that had recovered enough to be “delisted” by late 2023.

And yet the U.S., like the planet as a whole, faces a growing biodiversity crisis. Less than 6 percent of the animals and plants ever placed on the list have been delisted; many of the rest have made scant progress toward recovery. What's more, the list is far from complete: roughly a third of all vertebrates and vascular plants in the U.S. are vulnerable to extinction, says Bruce Stein, chief scientist at the National Wildlife Federation. Populations are falling even for species that aren't yet in danger. “There are a third fewer birds flying around now than in the 1970s,” Stein says. We're much less likely to see a White-throated Sparrow or a Red-winged Blackbird, for example, even though neither species is yet endangered.

The U.S. is far emptier of wildlife sights and sounds than it was 50 years ago, primarily because habitat—forests, grasslands, rivers—has been relentlessly appropriated for human purposes. The ESA was never designed to stop that trend, any more than it is equipped to deal with the next massive threat to wildlife: climate change. Nevertheless, its many proponents say, it is a powerful, foresightful law that we could implement more wisely and effectively, perhaps especially to foster stewardship among private landowners. And modest new measures, such as the Recovering America's Wildlife Act—a bill with bipartisan support—could further protect flora and fauna.

That is, if special interests don't flout the law. After the 1978 Supreme Court decision, Congress passed a special exemption to the ESA allowing the TVA to complete the Tellico Dam. The Snail Darter managed to survive because the TVA transplanted some of the fish from the Little Tennessee, because remnant populations turned up elsewhere in the Tennessee Valley, and because local rivers and streams slowly became less polluted following the 1972 Clean Water Act, which helped fish rebound.

Under pressure from people enforcing the ESA, the TVA also changed the way it managed its dams throughout the valley. It started aerating the depths of its reservoirs, in some places by injecting oxygen. It began releasing water from the dams more regularly to maintain a minimum flow that sweeps silt off the river bottom, exposing the clean gravel that Snail Darters need to lay their eggs and feed on snails. The river system “is acting more like a real river,” Matthews says. Basically, the TVA started considering the needs of wildlife, which is really what the ESA requires. “The Endangered Species Act works,” Matthews says. “With just a little bit of help, [wildlife] can recover.”

The trouble is that many animals and plants aren't getting that help—because government resources are too limited, because private landowners are alienated by the ESA instead of engaged with it, and because as a nation the U.S. has never fully committed to the ESA's essence. Instead, for half a century, the law has been one more thing that polarizes people's thinking.

I t may seem impossible today to imagine the political consensus that prevailed on environmental matters in 1973. The U.S. Senate approved the ESA unanimously, and the House passed it by a vote of 390 to 12. “Some people have referred to it as almost a statement of religion coming out of the Congress,” says Gary Frazer, who as assistant director for ecological services at the FWS has been overseeing the act's implementation for nearly 25 years.

Gopher Tortoise Gopherus polyphemus . Listed as Threatened: 1987. Status: Still threatened. Credit: ©Joel Sartore/National Geographic Photo Ark

But loss of faith began five years later with the Snail Darter case. Congresspeople who had been thinking of eagles, bears and Whooping Cranes when they passed the ESA, and had not fully appreciated the reach of the sweeping language they had approved, were disabused by the Supreme Court. It found that the legislation had created, “wisely or not ... an absolute duty to preserve all endangered species,” Chief Justice Warren E. Burger said after the Snail Darter case concluded. Even a recently discovered tiny fish had to be saved, “whatever the cost,” he wrote in the decision.

Was that wise? For both environmentalists such as Curry and many nonenvironmentalists, the answer has always been absolutely. The ESA “is the basic Bill of Rights for species other than ourselves,” says National Geographic photographer Joel Sartore, who is building a “photo ark” of every animal visible to the naked eye as a record against extinction. (He has taken studio portraits of 15,000 species so far.) But to critics, the Snail Darter decision always defied common sense. They thought it was “crazy,” says Michael Bean, a leading ESA expert, now retired from the Environmental Defense Fund. “That dichotomy of view has remained with us for the past 45 years.”

According to veteran Washington, D.C., environmental attorney Lowell E. Baier, author of a new history called The Codex of the Endangered Species Act, both the act itself and its early implementation reflected a top-down, federal “command-and-control mentality” that still breeds resentment. FWS field agents in the early days often saw themselves as combat biologists enforcing the act's prohibitions. After the Northern Spotted Owl's listing got tangled up in a bitter 1990s conflict over logging of old-growth forests in the Pacific Northwest, the FWS became more flexible in working out arrangements. “But the dark mythology of the first 20 years continues in the minds of much of America,” Baier says.

Credit: June Minju Kim ( map ); Source: David Matthews, Tennessee Valley Authority ( reference )

The law can impose real burdens on landowners. Before doing anything that might “harass” or “harm” an endangered species, including modifying its habitat, they need to get a permit from the FWS and present a “habitat conservation plan.” Prosecutions aren't common, because evidence can be elusive, but what Bean calls “the cloud of uncertainty” surrounding what landowners can and cannot do can be distressing.

Requirements the ESA places on federal agencies such as the Forest Service and the Bureau of Land Management—or on the TVA—can have large economic impacts. Section 7 of the act prohibits agencies from taking, permitting or funding any action that is likely to “jeopardize the continued existence” of a listed species. If jeopardy seems possible, the agency must consult with the FWS first (or the National Marine Fisheries Service for marine species) and seek alternative plans.

“When people talk about how the ESA stops projects, they've been talking about section 7,” says conservation biologist Jacob Malcom. The Northern Spotted Owl is a strong example: an economic analysis suggests the logging restrictions eliminated thousands of timber-industry jobs, fueling conservative arguments that the ESA harms humans and economic growth.

In recent decades, however, that view has been based “on anecdote, not evidence,” Malcom claims. At Defenders of Wildlife, where he worked until 2022 (he's now at the U.S. Department of the Interior), he and his colleagues analyzed 88,290 consultations between the FWS and other agencies from 2008 to 2015. “Zero projects were stopped,” Malcom says. His group also found that federal agencies were only rarely taking the active measures to recover a species that section 7 requires—like what the TVA did for the Snail Darter. For many listed species, the FWS does not even have recovery plans.

Endangered species also might not recover because “most species are not receiving protection until they have reached dangerously low population sizes,” according to a 2022 study by Erich K. Eberhard of Columbia University and his colleagues. Most listings occur only after the FWS has been petitioned or sued by an environmental group—often the Center for Biological Diversity, which claims credit for 742 listings. Years may go by between petition and listing, during which time the species' population dwindles. Noah Greenwald, the center's endangered species director, thinks the FWS avoids listings to avoid controversy—that it has internalized opposition to the ESA.

He and other experts also say that work regarding endangered species is drastically underfunded. As more species are listed, the funding per species declines. “Congress hasn't come to grips with the biodiversity crisis,” says Baier, who lobbies lawmakers regularly. “When you talk to them about biodiversity, their eyes glaze over.” Just this year federal lawmakers enacted a special provision exempting the Mountain Valley Pipeline from the ESA and other challenges, much as Congress had exempted the Tellico Dam. Environmentalists say the gas pipeline, running from West Virginia to Virginia, threatens the Candy Darter, a colorful small fish. The Inflation Reduction Act of 2022 provided a rare bit of good news: it granted the FWS $62.5 million to hire more biologists to prepare recovery plans.

The ESA is often likened to an emergency room for species: overcrowded and understaffed, it has somehow managed to keep patients alive, but it doesn't do much more. The law contains no mandate to restore ecosystems to health even though it recognizes such work as essential for thriving wildlife. “Its goal is to make things better, but its tools are designed to keep things from getting worse,” Bean says. Its ability to do even that will be severely tested in coming decades by threats it was never designed to confront.

T he ESA requires a species to be listed as “threatened” if it might be in danger of extinction in the “foreseeable future.” The foreseeable future will be warmer. Rising average temperatures are a problem, but higher heat extremes are a bigger threat, according to a 2020 study.

Scientists have named climate change as the main cause of only a few extinctions worldwide. But experts expect that number to surge. Climate change has been “a factor in almost every species we've listed in at least the past 15 years,” Frazer says. Yet scientists struggle to forecast whether individual species can “persist in place or shift in space”—as Stein and his co-authors put it in a recent paper—or will be unable to adapt at all and will go extinct. On June 30 the FWS issued a new rule that will make it easier to move species outside their historical range—a practice it once forbade except in extreme circumstances.

Credit: June Minju Kim ( graphic ); Brown Bird Design ( illustrations ); Sources: U.S. Fish & Wildlife Service Environmental Conservation Online System; U.S. Federal Endangered and Threatened Species by Calendar Year https://ecos.fws.gov/ecp/report/species-listings-by-year-totals ( annual data through 2022 ); Listed Species Summary (Boxscore) https://ecos.fws.gov/ecp/report/boxscore ( cumulative data up to September 18, 2023, and annual data for coral ); Delisted Species https://ecos.fws.gov/ecp/report/species-delisted ( delisted data through 2022 )

Eventually, though, “climate change is going to swamp the ESA,” says J. B. Ruhl, a law professor at Vanderbilt University, who has been writing about the problem for decades. “As more and more species are threatened, I don't know what the agency does with that.” To offer a practical answer, in a 2008 paper he urged the FWS to aggressively identify the species most at risk and not waste resources on ones that seem sure to expire.

Yet when I asked Frazer which urgent issues were commanding his attention right now, his first thought wasn't climate; it was renewable energy. “Renewable energy is going to leave a big footprint on the planet and on our country,” he says, some of it threatening plants and animals if not implemented well. “The Inflation Reduction Act is going to lead to an explosion of more wind and solar across the landscape.

Long before President Joe Biden signed that landmark law, conflicts were proliferating: Desert Tortoise versus solar farms in the Mojave Desert, Golden Eagles versus wind farms in Wyoming, Tiehm's Buckwheat (a little desert flower) versus lithium mining in Nevada. The mine case is a close parallel to that of Snail Darters versus the Tellico Dam. The flower, listed as endangered just last year, grows on only a few acres of mountainside in western Nevada, right where a mining company wants to extract lithium. The Center for Biological Diversity has led the fight to save it. Elsewhere in Nevada people have used the ESA to stop, for the moment, a proposed geothermal plant that might threaten the two-inch Dixie Valley Toad, discovered in 2017 and also declared endangered last year.

Does an absolute duty to preserve all endangered species make sense in such places? In a recent essay entitled “A Time for Triage,” Columbia law professor Michael Gerrard argues that “the environmental community has trade-off denial. We don't recognize that it's too late to preserve everything we consider precious.” In his view, given the urgency of building the infrastructure to fight climate change, we need to be willing to let a species go after we've done our best to save it. Environmental lawyers adept at challenging fossil-fuel projects, using the ESA and other statutes, should consider holding their fire against renewable installations. “Just because you have bullets doesn't mean you shoot them in every direction,” Gerrard says. “You pick your targets.” In the long run, he and others argue, climate change poses a bigger threat to wildlife than wind turbines and solar farms do.

For now habitat loss remains the overwhelming threat. What's truly needed to preserve the U.S.'s wondrous biodiversity, both Stein and Ruhl say, is a national network of conserved ecosystems. That won't be built with our present politics. But two more practical initiatives might help.

The first is the Recovering America's Wildlife Act, which narrowly missed passage in 2022 and has been reintroduced this year. It builds on the success of the 1937 Pittman-Robertson Act, which funds state wildlife agencies through a federal excise tax on guns and ammunition. That law was adopted to address a decline in game species that had hunters alarmed. The state refuges and other programs it funded are why deer, ducks and Wild Turkeys are no longer scarce.

The recovery act would provide $1.3 billion a year to states and nearly $100 million to Native American tribes to conserve nongame species. It has bipartisan support, in part, Stein says, because it would help arrest the decline of a species before the ESA's “regulatory hammer” falls. Although it would be a large boost to state wildlife budgets, the funding would be a rounding error in federal spending. But last year Congress couldn't agree on how to pay for the measure. Passage “would be a really big deal for nature,” Curry says.

Oyster Mussel. Epioblasma capsaeformis.  Listed as Endangered: 1997. Status: Still endangered. Credit: © Joel Sartore/National Geographic Photo Ark

The second initiative that could promote species conservation is already underway: bringing landowners into the fold. Most wildlife habitat east of the Rocky Mountains is on private land. That's also where habitat loss is happening fastest. Some experts say conservation isn't likely to succeed unless the FWS works more collaboratively with landowners, adding carrots to the ESA's regulatory stick. Bean has long promoted the idea, including when he worked at the Interior Department from 2009 to early 2017. The approach started, he says, with the Red-cockaded Woodpecker.

When the ESA was passed, there were fewer than 10,000 Red-cockaded Woodpeckers left of the millions that had once lived in the Southeast. Humans had cut down the old pine trees, chiefly Longleaf Pine, that the birds excavate cavities in for roosting and nesting. An appropriate tree has to be large, at least 60 to 80 years old, and there aren't many like that left. The longleaf forest, which once carpeted up to 90 million acres from Virginia to Texas, has been reduced to less than three million acres of fragments.

In the 1980s the ESA wasn't helping because it provided little incentive to preserve forest on private land. In fact, Bean says, it did the opposite: landowners would sometimes clear-cut potential woodpecker habitat just to avoid the law's constraints. The woodpecker population continued to drop until the 1990s. That's when Bean and his Environmental Defense Fund colleagues persuaded the FWS to adopt “safe-harbor agreements” as a simple solution. An agreement promised landowners that if they let pines grow older or took other woodpecker-friendly measures, they wouldn't be punished; they remained free to decide later to cut the forest back to the baseline condition it had been in when the agreement was signed.

That modest carrot was inducement enough to quiet the chainsaws in some places. “The downward trends have been reversed,” Bean says. “In places like South Carolina, where they have literally hundreds of thousands of acres of privately owned forest enrolled, Red-cockaded Woodpecker numbers have shot up dramatically.”

The woodpecker is still endangered. It still needs help. Because there aren't enough old pines, land managers are inserting lined, artificial cavities into younger trees and sometimes moving birds into them to expand the population. They are also using prescribed fires or power tools to keep the longleaf understory open and grassy, the way fires set by lightning or Indigenous people once kept it and the way the woodpeckers like it. Most of this work is taking place, and most Red-cockaded Woodpeckers are still living, on state or federal land such as military bases. But a lot more longleaf must be restored to get the birds delisted, which means collaborating with private landowners, who own 80 percent of the habitat.

Leo Miranda-Castro, who retired last December as director of the FWS's southeast region, says the collaborative approach took hold at regional headquarters in Atlanta in 2010. The Center for Biological Diversity had dropped a “mega petition” demanding that the FWS consider 404 new species for listing. The volume would have been “overwhelming,” Miranda-Castro says. “That's when we decided, ‘Hey, we cannot do this in the traditional way.’ The fear of listing so many species was a catalyst” to look for cases where conservation work might make a listing unnecessary.

An agreement affecting the Gopher Tortoise shows what is possible. Like the woodpeckers, it is adapted to open-canopied longleaf forests, where it basks in the sun, feeds on herbaceous plants and digs deep burrows in the sandy soil. The tortoise is a keystone species: more than 300 other animals, including snakes, foxes and skunks, shelter in its burrows. But its numbers have been declining for decades.

Urbanization is the main threat to the tortoises, but timberland can be managed in a way that leaves room for them. Eager to keep the species off the list, timber companies, which own 20 million acres in its range, agreed to figure out how to do that—above all by returning fire to the landscape and keeping the canopy open. One timber company, Resource Management Service, said it would restore Longleaf Pine on about 3,700 acres in the Florida panhandle, perhaps expanding to 200,000 acres eventually. It even offered to bring other endangered species onto its land, which delighted Miranda-Castro: “I had never heard about that happening before.” Last fall the FWS announced that the tortoise didn't need to be listed in most of its range.

Miranda-Castro now directs Conservation Without Conflict, an organization that seeks to foster conversation and negotiation in settings where the ESA has more often generated litigation. “For the first 50 years the stick has been used the most,” Miranda-Castro says. “For the next 50 years we're going to be using the carrots way more.” On his own farm outside Fort Moore, Ga., he grows Longleaf Pine—and Gopher Tortoises are benefiting.

Whooping Crane. Grus americana.  Listed as Endangered: 1967. Status: Still endangered. Credit: © Joel Sartore/National Geographic Photo Ark

The Center for Biological Diversity doubts that carrots alone will save the reptile. It points out that the FWS's own models show small subpopulations vanishing over the next few decades and the total population falling by nearly a third. In August 2023 it filed suit against the FWS, demanding the Gopher Tortoise be listed.

The FWS itself resorted to the stick this year when it listed the Lesser Prairie-Chicken, a bird whose grassland home in the Southern Plains has long been encroached on by agriculture and the energy industry. The Senate promptly voted to overturn that listing, but President Biden promised to veto that measure if it passes the House.

B ehind the debates over strategy lurks the vexing question: Can we save all species? The answer is no. Extinctions will keep happening. In 2021 the FWS proposed to delist 23 more species—not because they had recovered but because they hadn't been seen in decades and were presumed gone. There is a difference, though, between acknowledging the reality of extinction and deliberately deciding to let a species go. Some people are willing to do the latter; others are not. Bean thinks a person's view has a lot to do with how much they've been exposed to wildlife, especially as a child.

Zygmunt Plater, a professor emeritus at Boston College Law School, was the attorney in the 1978 Snail Darter case, fighting for hundreds of farmers whose land would be submerged by the Tellico Dam. At one point in the proceedings Justice Lewis F. Powell, Jr., asked him, “What purpose is served, if any, by these little darters? Are they used for food?” Plater thinks creatures such as the darter alert us to the threat our actions pose to them and to ourselves. They prompt us to consider alternatives.

The ESA aims to save species, but for that to happen, ecosystems have to be preserved. Protecting the Northern Spotted Owl has saved at least a small fraction of old-growth forest in the Pacific Northwest. Concern about the Red-cockaded Woodpecker and the Gopher Tortoise is aiding the preservation of longleaf forests in the Southeast. The Snail Darter wasn't enough to stop the Tellico Dam, which drowned historic Cherokee sites and 300 farms, mostly for real estate development. But after the controversy, the presence of a couple of endangered mussels did help dissuade the TVA from completing yet another dam, on the Duck River in central Tennessee. That river is now recognized as one of the most biodiverse in North America.

The ESA forced states to take stock of the wildlife they harbored, says Jim Williams, who as a young biologist with the FWS was responsible for listing both the Snail Darter and mussels in the Duck River. Williams grew up in Alabama, where I live. “We didn't know what the hell we had,” he says. “People started looking around and found all sorts of new species.” Many were mussels and little fish. In a 2002 survey, Stein found that Alabama ranked fifth among U.S. states in species diversity. It also ranks second-highest for extinctions; of the 23 extinct species the FWS recently proposed for delisting, eight were mussels, and seven of those were found in Alabama.

One morning this past spring, at a cabin on the banks of Shoal Creek in northern Alabama, I attended a kind of jamboree of local freshwater biologists. At the center of the action, in the shade of a second-floor deck, sat Sartore. He had come to board more species onto his photo ark, and the biologists—most of them from the TVA—were only too glad to help, fanning out to collect critters to be decanted into Sartore's narrow, flood-lit aquarium. He sat hunched before it, a black cloth draped over his head and camera, snapping away like a fashion photographer, occasionally directing whoever was available to prod whatever animal was in the tank into a more artful pose.

As I watched, he photographed a striated darter that didn't yet have a name, a Yellow Bass, an Orangefin Shiner and a giant crayfish discovered in 2011 in the very creek we were at. Sartore's goal is to help people who never meet such creatures feel the weight of extinction—and to have a worthy remembrance of the animals if they do vanish from Earth.

With TVA biologist Todd Amacker, I walked down to the creek and sat on the bank. Amacker is a mussel specialist, following in Williams's footsteps. As his colleagues waded in the shoals with nets, he gave me a quick primer on mussel reproduction. Their peculiar antics made me care even more about their survival.

There are hundreds of freshwater mussel species, Amacker explained, and almost every one tricks a particular species of fish into raising its larvae. The Wavy-rayed Lampmussel, for example, extrudes part of its flesh in the shape of a minnow to lure black bass—and then squirts larvae into the bass's open mouth so they can latch on to its gills and fatten on its blood. Another mussel dangles its larvae at the end of a yard-long fishing line of mucus. The Duck River Darter Snapper—a member of a genus that has already lost most of its species to extinction—lures and then clamps its shell shut on the head of a hapless fish, inoculating it with larvae. “You can't make this up,” Amacker said. Each relationship has evolved over the ages in a particular place.

The small band of biologists who are trying to cultivate the endangered mussels in labs must figure out which fish a particular mussel needs. It's the type of tedious trial-and-error work conservation biologists call “heroic,” the kind that helped to save California Condors and Whooping Cranes. Except these mussels are eyeless, brainless, little brown creatures that few people have ever heard of.

For most mussels, conditions are better now than half a century ago, Amacker said. But some are so rare it's hard to imagine they can be saved. I asked Amacker whether it was worth the effort or whether we just need to accept that we must let some species go. The catch in his voice almost made me regret the question.

“I'm not going to tell you it's not worth the effort,” he said. “It's more that there's no hope for them.” He paused, then collected himself. “Who are we to be the ones responsible for letting a species die?” he went on. “They've been around so long. That's not my answer as a biologist; that's my answer as a human. Who are we to make it happen?”

Robert Kunzig is a freelance writer in Birmingham, Ala., and a former senior editor at National Geographic, Discover and Scientific American .

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Collection  03 May 2022

Editor's choice: threatened species

Biodiversity is in crisis and according to some estimates tens of thousands of species disappear every year. Many others are on the verge of extinction. We can only halt this decline if we have a fundamental understanding of threatened species and are able to put in place effective conservation plans to guarantee their survival.

Following the IUCN Red List categories, this collection brings together some of the latest research on the biology and conservation efforts of a wide variety of threatened species from around the world.

Critically Endangered

State-space models reveal a continuing elephant poaching problem in most of Africa

• Scott Schlossberg
• Michael J. Chase
• Keith Lindsay

Enhanced, coordinated conservation efforts required to avoid extinction of critically endangered Eastern Pacific leatherback turtles

• The Laúd OPO Network

The conservation value of admixed phenotypes in a critically endangered species complex

• Keren R. Sadanandan
• Gabriel W. Low
• Frank E. Rheindt

Molecular phylogeny of one extinct and two critically endangered Central Asian sturgeon species (genus Pseudoscaphirhynchus ) based on their mitochondrial genomes

• Artem V. Nedoluzhko
• Fedor S. Sharko
• Nikolai S. Mugue

First use of artificial canopy bridge by the world’s most critically endangered primate the Hainan gibbon Nomascus hainanus

• Bosco Pui Lok Chan
• Yik Fui Philip Lo

Wild Bornean orangutans experience muscle catabolism during episodes of fruit scarcity

• Caitlin A. O’Connell
• Andrea L. DiGiorgio
• Erin R. Vogel

Chimpanzees balance resources and risk in an anthropogenic landscape of fear

• Elena Bersacola
• Catherine M. Hill
• Kimberley J. Hockings

Fine-scale genetic structure in the critically endangered red-fronted macaw in the absence of geographic and ecological barriers

• Guillermo Blanco
• Francisco Morinha
• José L. Tella

Mapping silver eel migration routes in the North Sea

• Pieterjan Verhelst
• Jan Reubens
• David Righton

Genome-wide SNPs redefines species boundaries and conservation units in the freshwater mussel genus Cyprogenia of North America

• Kyung Seok Kim
• Kevin J. Roe

Defining priority areas for blue whale conservation and investigating overlap with vessel traffic in Chilean Patagonia, using a fast-fitting movement model

• Luis Bedriñana-Romano
• Rodrigo Hucke-Gaete
• Daniel M. Palacios

High resolution biologging of breaching by the world’s second largest shark species

• Jessica L. Rudd
• Owen M. Exeter
• Lucy A. Hawkes

Deep genetic structure at a small spatial scale in the endangered land snail Xerocrassa montserratensis

• Cristina Català
• Vicenç Bros
• Marta Pascual

Shrub and vegetation cover predict resource selection use by an endangered species of desert lizard

• Christopher J. Lortie
• Jenna Braun
• H. Scott Butterfield

The endocast of the Night Parrot ( Pezoporus occidentalis ) reveals insights into its sensory ecology and the evolution of nocturnality in birds

• Andrew N. Iwaniuk
• Aubrey R. Keirnan
• Vera Weisbecker

Uncovering unique plasticity in life history of an endangered centenarian fish

• Martin J. Hamel
• Jonathan J. Spurgeon
• Mark A. Pegg

Effects of both climate change and human water demand on a highly threatened damselfly

• Rassim Khelifa
• Hayat Mahdjoub
• Michael J. Samways

Changes in diving behaviour and habitat use of provisioned whale sharks: implications for management

• Gonzalo Araujo
• Jessica Labaja
• Alessandro Ponzo

Protecting nursery areas without fisheries management is not enough to conserve the most endangered parrotfish of the Atlantic Ocean

• Natalia C. Roos
• Guilherme O. Longo
• Adriana R. Carvalho

Heterogeneity in patterns of helminth infections across populations of mountain gorillas ( Gorilla beringei beringei )

• Klara J. Petrželková
• Carine Uwamahoro
• David Modrý

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Research Article

Too few, too late: U.S. Endangered Species Act undermined by inaction and inadequate funding

Roles Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Visualization, Writing – original draft, Writing – review & editing

* E-mail: [email protected]

Affiliation Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York, New York, United States of America

Roles Conceptualization, Supervision, Writing – original draft, Writing – review & editing

Affiliations Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey, United States of America, Princeton School of Public and International Affairs, Princeton University, Princeton, New Jersey, United States of America

Affiliations Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey, United States of America, Santa Fe Institute, Santa Fe, New Mexico, United States of America

• Erich K. Eberhard, 
• David S. Wilcove, 
• Andrew P. Dobson

• Published: October 12, 2022
• https://doi.org/10.1371/journal.pone.0275322
• Reader Comments

This year, the Conference of Parties to the Convention on Biological Diversity will meet to finalize a post 2020-framework for biodiversity conservation, necessitating critical analysis of current barriers to conservation success. Here, we tackle one of the enduring puzzles about the U.S. Endangered Species Act, often considered a model for endangered species protection globally: Why have so few species been successfully recovered? For the period of 1992–2020, we analyzed trends in the population sizes of species of concern, trends in the time between when species are first petitioned for listing and when they actually receive protection, and trends in funding for the listing and recovery of imperiled species. We find that small population sizes at time of listing, coupled with delayed protection and insufficient funding, continue to undermine one of the world’s strongest laws for protecting biodiversity.

Citation: Eberhard EK, Wilcove DS, Dobson AP (2022) Too few, too late: U.S. Endangered Species Act undermined by inaction and inadequate funding. PLoS ONE 17(10): e0275322. https://doi.org/10.1371/journal.pone.0275322

Editor: Laurentiu Rozylowicz, University of Bucharest, ROMANIA

Received: June 10, 2022; Accepted: September 14, 2022; Published: October 12, 2022

Copyright: © 2022 Eberhard et al. This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: All data are within the paper and Supporting Information files. The species data and appropriations data underlying the results presented in this study were collected from notices published by the U.S. Fish & Wildlife Service and annual budget legislation, all of which are publicly available through the Federal Registrar ( www.federalregistrar.gov ). The author's accessed FWS Notices through the Service's Environmental Conservation Online System (ECOS), which organizes documents by species name. This data base is also publicly accessible ( https://ecos.fws.gov/ecp/ ).

Funding: The author(s) received no specific funding for this work.

Competing interests: The authors have declared that no competing interests exist.

Introduction

Accelerating rates of species extinction are a matter of global concern [ 1 ] as exemplified in the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) report that predicted the loss of over 1 million species in the foreseeable future, which will also have significant impacts on the delivery of ecosystem services [ 2 ]. The prevention of species extinction is a primary goal of the Convention on Biological Diversity and the UN Sustainable Development Goals. In the United States, the strongest law to prevent species extinctions is the Endangered Species Act (ESA) [ 3 ], which has served as a model for other nations since its passage by the Nixon Administration in 1973. A longstanding concern of both supporters and opponents of the law has been the relatively low number of listed species that have successfully recovered to the point where they no longer need protection. In the 48 years since enactment of the ESA, only 54 US species have been declared fully recovered and delisted [ 4 ].

Multiple explanations have been given for this low rate of recovery including: (a) a pattern of not protecting species until their populations have reached very low levels, which increases both the time to recovery and the likelihood that species will vanish entirely due to environmental, genetic, and demographic stochasticity [ 5 ]; (b) a lack of incentives to landowners to participate actively in efforts to increase populations of endangered species [ 6 ]; and (c) inadequate funding for recovery actions [ 7 ]. Here, we have used data from the Federal Register to examine trends in the population sizes of species at time of listing and the levels of funding available to list and recover them.

Evidence that species are not being protected under the ESA until their populations have reached dangerously low levels was initially provided in a 1993 paper by Wilcove et al. [ 8 ]. The authors found that the median population size at time of listing during the second decade of ‘legal protection’ by the ESA (1985–1991) was just 1075 for vertebrates and 999 individuals for invertebrates. The median population size at listing for plant species was less than 120 individuals. We repeated their methodology to determine whether the US Fish & Wildlife Service (FWS) has become more proactive as we approach the 50 th anniversary of the ESA and roughly 30 years since attention was first drawn to this problem.

We also examined trends in the length of time between when a species is identified as potentially deserving of protection and when it actually receives that protection under the ESA (hereafter, “wait times”). It should be noted that, in recent years, most of the species added to the ESA have been the result of petitions from non-governmental entities to FWS requesting protection of a given species. Frequently, listing follows litigation brought by environmental organizations when petition decisions are overdue or petitions are denied [ 9 ].

Finally, we examined trends in funding for the listing and recovery of imperiled species (we use “imperiled” to include both Endangered and Threatened species protected under the ESA, and, unless indicated otherwise, we use the word “species” to refer to any entity protected under the ESA, including subspecies and vertebrate populations). We give particular attention to trends in funding per species , in order to account for changes in the number of species listed each year.

Materials and methods

The list of plants and animals granted protection under the ESA was collated from annual listing records available through the U.S. Fish & Wildlife Service’s Environmental Conservation Online System (ECOS). Population data were obtained from Final and Proposed Listing Notices issued by the U.S. Fish & Wildlife Service. Our analysis was restricted to wild populations of plants and animals known to occur in the United States and its territories and did not include captive populations.

When presented with a range of values, or an upper limit, for the total number of individuals or populations at time of listing, we favored interpretations that maximized population size. For example, if a population was said to be “between 500 and 1000” individuals, we recorded the population as being 1000 individuals at time of listing. Similarly, a population said to be “<1000” was recorded as being 999 individuals at time of listing. This was done in order to obtain the largest possible estimate of each plant and animal population at time of listing, making our subsequent analyses an optimistic “best case scenario”. Six species were listed with no known individuals or populations surviving in the wild. In these instances, the total number of individuals or total number of populations was recorded as being zero. Population data for plants and animals listed between 1985–1991 were obtained from Wilcove et al. in order to facilitate comparison with their results. We performed a non-parametric Wilcoxon Rank-sum Test to compare the medians of continuous variable x , the number of individuals at time of listing for species listed between 1985–1992, and continuous variable y , the number of individuals at time of listing for species listed between 1993–2020. The same approach was used to compare the median number of populations at time of listing for each time period. We adopted a significance threshold of p = 0.05.

Data for Resource Management Appropriations (discretionary funding that supports the management and recovery of imperiled species by FWS) and Section 4 Appropriations (funding allocated specifically to ESA listing activities) were obtained from the text of annual federal budget legislation and corrected for inflation to 2019 USD. These documents are publicly accessible through the Federal Registrar . Funding per species was defined as the average funding available for the management of each species in a given year. We calculated this value by dividing annual Resource Management Appropriations by the total number of species protected under the ESA as of the first day of that calendar year.

From 1992–2020, the FWS listed a total of 970 species for protection under the ESA; 68% of these listings were plants, 18% were invertebrates, and 14% were vertebrates. Full species accounted for the majority of listings during this period (80%). Of the species listed, 602 had data on their total population size (total number of individuals) at time of listing, and 843 had data on the number of populations at time of listing. For each taxonomic group analyzed, the total population size at time of listing ( Fig 1A ) did not differ significantly between the 1985–1991 and 1992–2020 time periods (Wilcox Test values of p = 0.08, p = 0.41, and p = 0.66, for plants, vertebrates and invertebrates respectively). For plants and invertebrates, the total number of populations at time of listing ( Fig 1B ) also did not differ significantly between the 1985–1991 and 1992–2020 time periods (p = 0.91 and p = 0.06, respectively). However, the median number of vertebrate populations at time of listing was slightly greater in the 1992–2020 time period, increasing from 2 to 4 populations (p = 0.04).

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(A) Comparison of population size at time of listing for plants and animals. There are no significant differences between the two periods (Wilcox Test values of p = 0.08, p = 0.41, and p = 0.66, for plants, vertebrates and invertebrates respectively). (B) Comparison of number of populations at time of listing. There are no significant differences between the two periods for plants and invertebrates. Values of zero indicate species for which there were either no known individuals or no known populations at time of listing. Median values shown above each plot.

https://doi.org/10.1371/journal.pone.0275322.g001

Our analysis revealed longer wait times for species petitioned for listing during the 2000–2009 period (median = 9.1 years), compared to those petitioned for listing during the 1992–1999 period (median = 5.9 years), followed by shorter wait times for species petitioned for listing during the 2010–2020 period (median 3.0 years). The number of petitions received during each period also varied greatly ( n = 49, 203 and 26 for 1992–1999, 2000–2009 and 2010–2020, respectively). While wait times seem to decrease when fewer species are listed, there are insufficient data to test whether this effect is significant.

Resource Management Appropriations climbed modestly from 1996–2010 before beginning a decade-long decline that was halted only in 2020 ( Fig 2A ). The same trend is observed in Section 4 Appropriations, which peaked in 2010 at $25.9 million USD before dropping to $20.1 million USD by 2020. Concurrently, the number of species listed for protection under the ESA increased by over 300% between 1985–2020. As such, Resource Management Appropriations, when measured on a per species basis, have dropped by nearly 50% since 1985.

(A) Change in cumulative number of ESA listings compared to change in Resource Management Appropriations. The lower timeline illustrates political control of the Presidency and, by a majority, each house of Congress. (B) Number of species delisted for various reasons.

https://doi.org/10.1371/journal.pone.0275322.g002

Our analysis of trends in the protection of imperiled species under the US Endangered Species Act warrants a limited amount of optimism and a larger amount of pessimism: Most species are not receiving protection until they have reached dangerously low population sizes. First reported in 1993, this pattern has persisted throughout the intervening quarter century. We suspect that most of the species listed since 1993 had fallen to low population levels well before the time span of our study, a reflection of past anthropogenic activities. Their protection under the ESA implies a painfully slow process of clearing a backlog of rare but unprotected species as opposed to a failure to respond to recent, rapid population declines in formerly more common species.

The wait-times between when a species is first petitioned for protection under the ESA and when it finally receives that protection have waxed and waned since 1992. The period with the longest median wait time (2000–2009, with a median wait-time of 9.1 years), was also the period when the greatest number of petitions were received by FWS ( n = 203). The period with the shortest median wait time (2010–2020 with a median wait-time of 3.0 years) was the period when the fewest number of petitions were received ( n = 26). This suggests that wait times may be exacerbated when limited resources for listing are strained by a large influx of petitions. Consistently, very few species have received protection in the two-year period that is prescribed in the ESA. For species with very small or rapidly declining populations, a multi-year delay in receiving protection increases the risk of extinction.

Our data suggest that inadequate funding has persisted for decades, with no clear relationship as to which political party is in power ( Fig 2A ). The unfortunate conclusion is that FWS is being asked to do more with less resources. The combination of delays in listing rare species, the typically mall population sizes of species at time of listing, and inadequate funding for recovery actions, are the key factors that can explain the relatively small number of listed species that have fully recovered ( Fig 2B ). Resource allocation frameworks and other decision-support tools can help FWS make the most efficient use of the funds it receives [ 10 ], but increased funding is essential for sustained, substantial progress in protecting imperiled species [ 11 , 12 ]. Studies have shown that government expenditures for imperiled species management do contribute to an improvement in recovery status and averted extinctions [ 13 ].

Although the US is one of only a handful of nations that have failed to ratify the Convention on Biological Diversity, its commitment to preventing the loss of its own “non-voting” species dates back nearly half a century to the passage of the ESA in 1973. In December 2022, when international leaders gather in Montréal, Canada for the 15 th meeting of the Conference of Parties to the Convention on Biological Diversity, the failure of the US to have solved the funding gaps that hamper the ESA will stand as a stark reminder of the difference between a visionary promise and its functional implementation.

Supporting information

https://doi.org/10.1371/journal.pone.0275322.s001

• View Article
• PubMed/NCBI
• Google Scholar
• 2. Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, (IPBES). Global assessment report on biodiversity and ecosystem services of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. IPBES Secretariat. 2019. Available from: https://ipbes.net/global-assessment
• 3. United States. The Endangered Species Act, Public Law 93–205, Section 3. Washington D.C. 1973.

REPORTS, ARTICLES AND RESEARCH PAPERS

Endangered species.

    • Paving the Road to Extinction: Congress’ Expanded Assault on Endangered Species Through Appropriations Poison-Pill Riders .Kurose, S., and Hartl, B., Center for Biological Diversity, January 2024.     • Recovery of the Grizzly Bear at the Intersection of Law and Science . Greenwald, N. August 2023.     • No Refuge: How America’s National Wildlife Refuges Are Needlessly Sprayed With Nearly Half a Million Pounds of Pesticides Each Year . Connor, H. May 2018.     • Mexico's 10 Most Iconic Endangered Species . Olivera, A. April 2018.      • A Wall in the Wild: The Disastrous Impacts of Trump's Border Wall on Wildlife . Greenwald, N., Segee, B., Curry, T. and Bradley, C. May 2017.      • Pollinators in Peril: A Systematic Status Review of North American and Hawaiian Native Bees . Kopec, K., Center for biological Diversity, February 2017.      • Removing the Walls to Recovery: Top 10 Species Priorities for a New Administration. Endangered Species Coalition (including the Center). December 2016.      • Shortchanged: Funding Needed to Save America's Most Endangered Species . Greenwald, N., Hartl, , B., Mehrhoff, L., Pang, J. December 2016.      • Taxa, Petitioning Agency, and Lawsuits Affect Time Spent Awaiting Listing Under the US Endangered Species Act . Greenwald, N., Kesler, D., Puckett, E. Biological Conservation . September 2016.      • Fishing Down Nutrients on Coral Reefs . Allgeier, J.E., Valdivia,A., Cox, C. & Layman, C.A. Nature Communications . August 2016.      • A Wild Success: A Systematic Review of Bird Recovery Under the Endangered Species Act . Suckling, K., Mehrhoff, L., 2016. Beam, R. & Hartl, B. June 2016.      • Poisoned Waters: How Cyanide Fishing and the Aquarium Trade Are Devastating Coral Reefs and Tropical Fish . Center for Biological Diversity & For the Fishes. June 2016.     • Lethal Loophole: How the Obama Administration Is Increasingly Allowing Special Interests to Endanger Rare Wildlife . Sanerib, T., Elkins, C., and Greenwald, N. February 2016.     • Biodiversity on the Brink: The Role of “Assisted Migration" in Managing Endangered Species Threatened With Rising Seas . Lopez, J. Harvard Environmental Law Review Vol. 39. 2015.     • Politics of Extinction: The Unprecedented Republican Attack on Endangered Species and the Endangered Species Act . Pand, J., and Greenwald, N. July 2015.     • Runaway Risks: Oil Trains and the Government's Failure to Protect People, Wildlife and the Environments . Margolis, J., 2015.     • Sea-Level Rise and Species Survival along the Florida Coast . Lopez, J. 2014.     • Collision Course: The Government's Failing System for Protecting Florida Manatees from Deadly Boat Strikes . Center for Biological Diversity. September 2014.      • Nourished by Wildfire: The Ecological Benefits of the Rim Fire and the Threat of Salvage Logging . Center for Biological Diversity and John Muir Projejct, January 2014.      • Deadly Waters: How Rising Seas Threaten 233 Endangered Species . Center for Biological Diversity. 2013.     • In Harm's Way: How the U.S. State Department and U.S. Fish and Wildlife Service Have Ignored the Dangers of the Keystone XL Pipeline to Endangered Species . Burd, L., Greenwald, N., & Bradley, C., 2013.     • Dying for Protection: The 10 Most Vulnerable, Least Protected Amphibians and Reptiles in the United States . Adkins Giese, C. 2013.     • On Thin Ice: After Five Years on the Endangered Species List, Polar Bears Still Face a Troubling Future . Center for Biological Diversity. 2013.     • A Poor Track Record, but a Chance to Excel . Snape, W., 2013. The Environmental FORUM   Environmental Law Institute, www.eli.org ) 30(1): 53.     • Can A Multi-Species Habitat Conservation Plan Save San Diego's Vulnerable Vernal Pool Species? Buse, J., 2012. Golden Gate University Environmental Law Journal 6(1): 52-80.     • On Time, On Target: How the Endangered Species Act Is Saving America's Wildlife . Suckling, K., Greenwald, N., Curry, T. 2012.     • Protecting Rare Amphibians Under the U.S. Endangered Species Act . Adkins Giese, C., FrogLog (May 2012): 21-23.     • White-nose Syndrome Headed to a Cave Near You . Matteson, M. Desert Report (June 2011): 6-7.     • Impact of Dunes Sagebrush Lizard on Oil and Gas Activities in New Mexico . Lininger, J. & Bradley, C., 2011.    • Assessing Protection for Imperiled Species of Nevada, U.S.A.: Are Species Slipping Through the Cracks of Existing Protections? Bradley, C. & Greenwald, N., 2008.     • Not Too Late to Save the Polar Bear: A Rapid Action Plan to Address the Arctic Meltdown . Siegel, K., Cummings, B., Moritz, A. & Nowicki, B., 2007.     • Status of the Bald Eagle in the Lower 48 States and the District of Columbia: 1963-2007 . Suckling, K. & Hodges, W., 2007.     • The Bureaucratically Imperiled Mexican Wolf . Povilitis, A., Parsons, D.R., Robinson, M.J., & Becker, C.D., 2006.     • A Review of Northern Goshawk Habitat Selection in the Home Range and Implications for Forest Management in the Western United States . Greenwald, D. N., Crocker-Bedford, C., Broberg, l., & Suckling, K., 2005.     • Suitable Habitat for Jaguars in New Mexico . Robinson, M., Bradley, C., Boyd, J., 2005.     • Impacts of the 2003 Southern California Wildfires on Four Species Listed as Threatened or Endangered Under the Federal Endangered Species Act: Quino Checkerspot Butterfly, Mountain Yellow-legged Frog, Coastal California Gnatcatcher, Least Bell's Vireo . Bond, M. & Bradley, C., 2003.     • A Conservation Alternative for the Management of the Four Southern California National Forests (Los Padres, Angeles, San Bernardino, Cleveland) . 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ENDANGERED SPECIES ACT

   • Taxa, Petitioning Agency, and Lawsuits Affect Time Spent Awaiting Listing Under the US Endangered Species Act . Greenwald, N., Kesler, D., Puckett, E. Biological Conservation . September 2016.     • A Wild Success: A Systematic Review of Bird Recovery Under the Endangered Species Act . Suckling, K., Mehrhoff, L., Beam, R. & Hartl, B. June 2016.     • Saving Species and Wild Spaces: 10 Extraordinary Places Saved by the Endangered Species Act , Pang, J. & Hartl, B. May 2016.     • Politics of Extinction: The Unprecedented Republican Attack on Endangered Species and the Endangered Species Act . Pang, J., and Greenwald, N. July 2015.     • A Different Perspective on the Endangered Species Act at 40 Responding to Damien M. Schiff . Buse, J., 2015. University of California, Davis 38(1): 145-166.     • Making Room for Wolf Recovery: The Case for Maintaining Endangered Species Act Protections for America's Wolves . Weiss, A., Greenwald, N. & Bradey, C. Center for Biological Diversity, November 2014.     • A Wild Success: American Voices on the Endangered Species Act at 40 . Center for Biological Diversity, Endangered Species Coalition, Defenders of Wildlife, February 2014.     • On Time, On Target: How the Endangered Species Act Is Saving America's Wildlife . Suckling, K., Greenwald, N., Curry, T., 2012.     • A Future for All: A Blueprint for Strengthening the Endangered Species Act . 2011.     • Effects on Species' Conservation of Reinterpreting the Phrase “Significant Portion of its Range” in the U.S. Endangered Species Act . Greenwald, N., 2009. Conservation Biology 23(6): 1375-1377.     • State Endangered Species Acts . In Baur, D.C. & Irvin, W.R. (eds.), Endangered Species Act: Law, Policy, and Perspectives , second edition. American Bar Association. George, S. & Snape, W., 2010.     • Politicizing Extinction: The Bush Administration's Dangerous Approach to Endangered Wildlife . Greenwald, N., 2007.     • Measuring the Success of the Endangered Species Act, Recovery Trends in the Northeastern United States . Suckling, K.F., 2006.     • Factors Affecting the Rate and Taxonomy of Species Listings under the US Endangered Species Act . In Gobel, D, Scott, M.J. & Davis, F.W. (eds.), The Endangered Species Act at Thirty: Renewing the Conservation Commitment . Island Press. Greenwald, D.N., Suckling, K.F. & Taylor, M.F.J., 2006.     • Critical Habitat and Recovery . In: Gobel, D., Scott, M.J. & Davis, F.W. (eds.), The Endangered Species Act at Thirty: Renewing the Conservation Commitmen t. Island Press. Suckling, K.F. & Taylor, M.F.J., 2006.     • The Listing Record . In Gobel, D., Scott, M.J., & Davis, F.W. (eds.), The Endangered Species Act at Thirty: Renewing the Conservation Commitmen t. Island Press. Greenwald, D.N., K.F. Suckling and M.F.J. Taylor, 2006.      • Progress or Extinction? A Systematic Review of the U.S. Fish and Wildlife Service's Endangered Species Act Listing Program. 1974-2004 . Greenwald, D. N. & Suckling, K. F., 2005     • The Effectiveness of the Endangered Species Act: A Quantitative Analysis . Taylor, M.F.J., Suckling, K.F. & Rachlinski, J.J., 2005. BioScience 55(4): 360-367.     • Extinction and the Endangered Species Act . Suckling, K., Nowicki, B. & Slack, R., 2004.     • A Review of the Bush Critical Habitat Record . 2003.     • Bush Administration Attacks Endangered Species Act .     • Safeguarding Citizen Rights Under the Endangered Species Act . Senatore, M., & Suckling, K., 2001.

BIODIVERSITY

    • Hidden In Plain Sight: California's Native Habitats Are Valuable Carbon Sinks . Yap, T., Prabhala, A., Anderson, I. Center for Biological Diversity. July 2023.     • Bullfrogs: A Trojan Horse for a Deadly Fungus? Yap, T., Koo, M., Ambrose, R., Vredenburg, V.T. Science Journal for Kids . October 2018.     • Mexico's 10 Most Iconic Endangered Species . Olivera, A. April 2018.     • A Multi-method Approach to Delineate and Validate Migratory Corridors . Bond, M., Bradley, C., Kiffner, C., Morrison, T., and Lee, D. Landscape Ecology . May 2017.    • Biodiversity on the Brink: The Role of “Assisted Migration" in Managing Endangered Species Threatened With Rising Seas . Lopez, J. Harvard Environmental Law Review Vol. 39. 2015.    • Nourished by Wildfire: The Ecological Benefits of the Rim Fire and the Threat of Salvage Logging . Center for Biological Diversity and John Muir Projejct, January 2014.    • Joining the Convention on Biological Diversity: A Legal and Scientific Overview of Why the United States Must Wake Up . Snape, B., 2010. Sustainable Development Law & Policy 10(3): 6-18.    • Highways to Hell: A Critical Examination of the Environmental Impacts of the Security and Prosperity Partnership . Lopez, J., 2009. [3 MB version]    • Rana Aurora (Northern Red-legged Frog) Egg Mass Disturbance. Curry, T. R., and Hayes, M. P., 2009. Herpetological Review 40(2): 208-209.    • Greenwashing Risks to Baby-boomers Abroad: An Assessment of Available Strategies to Address “Green” Marketing Misrepresentation to U.S. Retiree Real Estate Investors Overseas. 2009.    • Life History Diversity and Protection of the Southwestern Washington/Columbia River Distinct Population Segment of the Coastal Cutthroat Trout . Greenwald, N. & Mashuda, S., 2008.     • Predation on the Coastal Tailed Frog ( Ascaphus truei ) by a Shrew ( Sorex spp.) in Washington State . Lund, E., Hayes, M., Curry, T., Marsten, J. & Young, 2008. Northwestern Naturalist 89(3): 200-202.     • Assessing Protection for Imperiled Species of Nevada, U.S.A.: Are Species Slipping Through the Cracks of Existing Protections? Greenwald, N. & Bradley, C., 2008.     • Medicinal Plants at Risk — Nature's Pharmacy, Our Treasure Chest: Why We Must Preserve Our Natural Heritage . Roberson, E., 2008.     • Species of Concern of the Tillamook Rainforest and North Coast, Oregon . Greenwald, N. & Garty, A., 2007.     • The Bering Sea: A Biodiversity Assessment of Vertebrate Species . Greenwald, N., Callimanis, S., Garty, A. & Peters, E., 2006.     • Saving All the Parts: Protecting Species of Northwest Old-growth Forests . Greenwald, N. & Greason, S., 2004.     • Imperiled Western Trout and the Importance of Roadless Areas . 2001.     • A Conservation Alternative for the Management of the Four Southern California National Forests (Los Padres, Angeles, San Bernardino, Cleveland) . Penrod, K., et al., 2002.     • Principles of Wildlife Corridor Design . Bond, M., 2003.

    • A  Wall  of  Lights  Through the Wild: 1,800 Stadium Lights on Arizona Conservation Lands Threaten Wildlife . McSpadden, R., Jordahl, L., and Bradley, C. Center for Biological Diversity. June 2023.     • Hidden In Plain Sight: California's Native Habitats Are Valuable Carbon Sinks . Yap, T., Prabhala, A., Anderson, I. Center for Biological Diversity. July 2023.     • Deadpool Highway: How Interstate 11 Would Worsen Arizona’s Water Crisis . McSpadden, R., and Bradley, C. Center for Biological Diversity. May 2023.     • State of Utom River 2022: Challenges, Opportunities for Southern California’s Signature River . Center for Biological Diversity. August 2022.     • A Wall in the Wild: The Disastrous Impacts of Trump's Border Wall on Wildlife . Greenwald, N., Segee, B., Curry, T. and Bradley, C. May 2017.     • A Multi-Method Approach to Delineate and Validate Migratory Corridors . Bond, M., Bradley, C., Kiffner, C., Morrison, T., and Lee, D. Landscape Ecology . May 2017.     • Public Lands Enemies: 15 Federal Lawmakers Plotting to Seize, Destroy and Privatize America's Public Lands . Spivak, R. & Beam, R. March 2017.     • Runaway Risks: Oil Trains and the Government's Failure to Protect People, Wildlife and the Environments . Margolis, J., 2015.     • Nourished by Wildfire: The Ecological Benefits of the Rim Fire and the Threat of Salvage Logging . Center for Biological Diversity and John Muir Projejct, January 2014.     • Groups Join Together to Confront Water-rights Issue . Mrowka, R. Desert Report (June 2011): 2, 13.     • Saving Our National Legacy: The Future of America's Last Heritage Forests . Fink, M., Kassar, C., Matteson, M., and McKinnon, T., July 2009.     • America's Newest Fossil Beds National Monument: Tule Springs/Upper Las Vegas Wash . Mrowka, R. and Davis, L., 2009.     • Wild at Heart: Saving the Last of America's Backcountry . 2008.     • Imperiled Western Trout and the Importance of Roadless Areas . 2001.     • Protection and Conservation of Roadless Areas in the Southwest . Greenwald, N.     • A Conservation Alternative for the Management of the Four Southern California National Forests (Los Padres, Angeles, San Bernardino, Cleveland) . Penrod, K., et al., 2002.

CLIMATE CHANGE

   • Flight Path: A Trajectory for U.S. Aviation to Meet Global Climate Goals . Center for Biological Diversity. October 2020.    • From Bailout to Righting the Course: The Commonsense Action the United States Must Take to Address the Flood Crisis . Lopez, J. 2020.    • Stealing California's Future: How Monterey County's Dirty Oil Business Worsens the Climate Crisis . Center for Biological Diversity. September 2016.    • Throwing Shade: 10 Sunny States Blocking Distributed Solar Development . Greer, R. April 2016.    • Up in the Air: How Airplane Carbon Pollution Jeopardizes Global Climate Goals . Pardee, V. December 2015.    • Biodiversity on the Brink: The Role of “Assisted Migration" in Managing Endangered Species Threatened With Rising Seas . Lopez, J. Harvard Environmental Law Review Vol. 39. 2015.    • Grounded: The President's Power to Fight Climate Change, Protect Public Lands by Keeping Publicly Owned Fossil Fuels in the Ground . Saul, M., McKinnon, T., Spivak, R., 2015.    • What Happens When Species Move But Reserves Do Not? Creating Climate Adaptive Solutions to Climate Change . Whipps, N., 2015. Hastings Law Journal Vol. 66.    • Runaway Risks: Oil Trains and the Government's Failure to Protect People, Wildlife and the Environments . Margolis, J., 2015.    • The Potential Greenhouse Gas Emissions From U.S. Federal Fossil Fuels . Ecoshift Consulting, Center for Biological Diversity, Friends of the Earth. August 2015.    • Troubled Waters: Offshore Fracking's Threat to California's Ocean, Air and Seismic Stability . Center for Biological Diversity, 2014.    • On Shaky Ground: Fracking, Acidizing, and Increased Earthquake Risk in California . Earthworks, Center for Biological Diversity, Clean Water Action, 2014.    • Deadly Waters: How Rising Seas Threaten 233 Endangered Species . Center for Biological Diversity, 2013.    • The New Normal: Climate Change Victims in Post- Kiobel United States Federal Courts . Lopez, J., 2013. Charleston Law Review 8(1).    • Not Just a Number: Achieving a CO 2 Concentration of 350 ppm or Less to Avoid Catastrophic Climate Impacts. Center for Biological Diversity and 350.org, 2010.    • Extinction: It's Not Just for Polar Bears. A Center for Biological Diversity and Care for the Wild International report. Wolf, S., 2010.    • Yes, He Can: President Obama's Power to Make an International Climate Commitment Without Waiting for Congress . Bundy, K., Cummings, B., Pardee, V. & Siegel, K., 2009.    • 350 Reasons We Need to Get to 350: Species Threatened by Global Warming; An Interactive Installation by the Center for Biological Diversity . 2009.    • No Reason to Wait: Reducing Greenhouse Gas Emissions Through the Clean Air Act . Siegel, K., Snape, W., and Vespa, M., June 2009.    • Why 350? Climate Policy Must Aim to Stabilize Greenhouse Gases at the Level Necessary to Minimize the Risk of Catastrophic Outcomes . Vespa, M., 2009. Ecology Law Currents 36(1): 185-194. • Fuel to Burn: The Climate and Public Health Implications of Off-road Vehicle Pollution in California . Kassar, C. & Spitler, P., 2008.     • Not Too Late to Save the Polar Bear: A Rapid Action Plan to Address the Arctic Meltdown . Siegel, K., Cummings, B., Moritz, A. & Nowicki, B., 2007.     • The California Environmental Quality Act: On the Front Lines of California's Fight Against Global Warming . Siegel, K., Vespa, M. & Nowicki, B., 2007.

    • Powerless in the United States: How Utilities Drive Shutoffs and Energy Injustice . Center for Biological Diversity, March 2023.     • Rooftop-Solar Justice: Why Net Metering is Good for People and the Planet and Why Monopoly Utilities Want to Kill It . Crystal,. H., Lin, R., and Su, J., Center for Biological Diversity, Energy and Policy Institute, BailoutWatch, January 2023.    • Fueling Extinction: How Dirty Energy Drives Wildlife to the Brink . Endangered Species Coalition (incl. the Center for Biological Diversity), 2012.    • A Deadly Toll: The Gulf Oil Spill and the Unfolding Wildlife Disaster . 2011. Center for Biological Diversity.    • What We Should Learn From the BP Spill . Lopez, J., 2011. Environmental Law News 20 (1): 35.    • Too Much Oil for the Rubber Stamp: The Government's Role in the BP Oil Spill . Lopez, J., 2011.    • BP's Well Evaded Environmental Review: Categorical Exclusion Policy Remains Unchanged . Lopez, J., 2010. Ecology Law Currents 37 (93): 93-103.    • Corporate Profile of Salt River Project . Draffan, G., 2001.    • Ecological and Community Problems with Biomass-to-Energy . Schulke, T.

ENVIRONMENTAL HEALTH/POLLUTION

    • Collateral Damage: How Factory Farming Drives Upthe Use of Toxic Agricultural Pesticides . Center for Biological Diversity, World Animal Protection, 2022.     • Pesticides and Environmental Injustice in the USA: Root Causes, Current Regulatory Reinforcement and a Path Forward . Donley, N., Bullard, R., Economos, J., Figueroa, I., Lee, J., Liebman, A., Navarro Martinez, D., & Shafiei, F. BMC Public Health , April 2022.     • Toxic Hangover: How the EPA Is Approving New Products With Dangerous Pesticides It Committed to Phasing Out . Donley, N., Jan. 2020.     • A Menace to Monarchs: Drift-prone Dicamba Poses a Dangerous New Threat to Monarch Butterflies . Donley, N., March 2018.     • Toxic Concoctions: How the EPA Ignores the Dangers of Pesticide Cocktails . Donley, N., July 2016.     • Can't We Just All Get Along: Reconciling Pesticide Use and Species Protection . Lopez, J. 2015.     • Lost in the Mist: How Glyphosate Use Disproportionately Threatens California's Most Impoverished Counties . Center for Biological Diversity, 2015.       • Perdido en la niebla: Como El uso de glifosato desproporcionadamente amenaza los condados más pobres de California . Center for Biological Diversity, 2015.     • Dispersants: The Lesser of Two Evils or a Cure Worse Than the Disease? Kilduff, C. and Lopez, J., 2012. Ocean and Coastal Law Journal 16 (2): 375-394.     • Endocrine-disrupting Chemical Pollution: Why the EPA Should Regulate These Chemicals Under the Clean Water Act . Lopez, J., 2010. Sustainable Development Law & Policy 10(3): 19-23.     • Poisoning Our Imperiled Wildlife: San Francisco Bay Area Endangered Species at Risk from Pesticides . Miller, J., Miller, J., Beeland, T.D. & Bradley, C., 2006.     • Silent Spring Revisited: Pesticide Use and Endangered Species . Litmans, B. & Miller, J, 2004.

POPULATION AND SUSTAINABILITY

    • Alternative Economies: Uplifting Activities for a Sustainable Future . Dennings, K., Adoma, A.; 2023.     • At What Cost: Unraveling the Harms of the Fast Fashion Industry . Shedlock, K., Feldstein, S.; 2023.     • Too Hot for Knitwear: Climate Crisis, Biodiversity and Fashion Brands Using Woll and Synthetics . Feldstein, S., Hakansson, E.; 2023.     • Talking Trash: U.S. Perspectives on the Language of Waste Reduction . Dennings, K., Adoma, A.; 2023.     • Unwrapped: Perceptions of Winter Holiday Consumerism, Gift Giving and Waste . Dennings, K., Adoma, A; 2023.     • The Influence of Environmental Toxicity, Inequity and Capitalism on Reproductive Health . Dennings, K., Grossman, A; 2022.     • Gender and the Climate Crisis: Equitable Solutions for Climate Plans . Dennings, K., Baillie, S., and Baxter, C; 2022.     • Public Perceptions on Population: US Survey Results . Dennings, K., Baillie, S., Ricciardi, R. and Addo, A; 2022; Population and Sustainability 6(1): 1-23.     • Sheer Destruction: Wool, Fashion and the Biodiversity Crisis . Feldstein, S., Hakansson, E., Katcher, J., Vance, V.; 2021.     • Endangered Species Condoms: A Social Marketing Tool for Starting Conversations About Population . Baillie, S., Dennings, K. and Feldstein S.; 2020; Journal of Population and Sustainability 4(2): 31-44.     • Contraception and Consumption in the Age of Extinction: U.S. Survey Results . Dennings, K., 2020.     • Appetite for Change: A Policy Guide to Reducing Greenhouse Gas Emissions of U.S. Diets by 2030 . Feldstein, S., 2020.     • Catering to the Climate: How Earth-Friendly Menus at Events Can Help Save the Planet . Molidor, J., Emery., I., 2019.     • Towards a Psychology of the Food‐Energy‐Water Nexus: Costs and Opportunities . Dreyer, S.J., Kurz, T., Prosser, A.M.B., Abrash, A.W., Dennings, K., McNeill, I., Saber, D.A., Swim, J.K., 2019. Journal of Social Issues 76(1).     • Slow Road to Zero: A Report Card on U.S. Supermarkets’ Path to Zero Food Waste . Molidor, J., Feldstein, S., Figueiredo, J., 2019.     • Checked Out: How U.S. Supermarkets Fail to Make the Grade in Reducing Food Waste . Molidor, J., Feldstein, S., 2018.     • Wasting Biodiversity: Why Food Waste Needs to Be a Conservation Priority . Feldstein, S., 2017. Biodiversity 18 (2-3): 75-77.     • Habitat-Fed Food: Grass-fed Beef and Sustainable Solutions . Molidor, J., 2017. Biodiversity 18 (2-3): 78-81.

FIRE AND FOREST RESTORATION

    • Nourished by Wildfire: The Ecological Benefits of the Rim Fire and the Threat of Salvage Logging . Center for Biological Diversity and John Muir Projejct, January 2014.     • Influence of Pre-Fire Tree Mortality on Fire Severity in Conifer Forests of the San Bernardino Mountains, California , 2009. Bond, M., Lee, D. E., Bradley, C. & Hanson, T. Open Forest Science Journal 2:41-47.     • Impacts of the 2003 Southern California Wildfires on Four Species Listed as Threatened or Endangered Under the Federal Endangered Species Act: Quino Checkerspot Butterfly, Mountain Yellow-legged Frog, Coastal California Gnatcatcher, Least Bell's Vireo . Bond, M. & Bradley, C., 2003.     • Ecological Restoration of Southwestern Ponderosa Pine Ecosystems: A Broad Perspective . Allen, C.D., Savage, M., Falk, D.A., Suckling, K. F., Swetnam, T. W., Schulke, T., Stacey, P. B., Morgan, P., Hoffman, M. & Klingel, J. T., 2002. Ecological Applications 12(5): 1418-1433.     • Prelude to Catastrophe: Recent and Historic Land Management within the Rodeo-Chedeski Fire Area .     • Effectively Treating the Wildland-Urban Interface to Protect Houses and Communities from the Threat of Forest Fire . Nowicki, B., 2002.     • Protection and Conservation of Roadless Areas in the Southwest . Greenwald, N.     • An Ecologically Integrated Approach to Managing Dwarf Mistletoe (Arceuthobium) in Southwest Forests .  Pollock, Michael M., Ph. D.  Kieran Suckling, 1995.      • A Conservation Alternative for the Management of the Four Southern California National Forests (Los Padres, Angeles, San Bernardino, Cleveland) . Penrod, K., et al., 2002.     • Fire & Forest Ecosystem Health in the American Southwest . Suckling, K., 1996.

LIVESTOCK GRAZING

    • Costs and Consequences: The Real Price of Livestock Grazing on America's Public Lands . Glaser, C., Romaniello, C. & Moskowitz, K. (prepared for the Center for Biological Diversity), 2015.     • Assessing the Full Cost of the Federal Grazing Program . Moskowitz, K., & Romaniello, C., 2002.     • Ecological Restoration of Southwestern Ponderosa Pine Ecosystems: A Broad Perspective . Allen, C.D., Savage, M., Falk, D.A., Suckling, K.F., Swetnam, T.W., Schulke, T., Stacey, P.B., Morgan, P., Hoffman, M. & Klingel, J.T., 2002. Ecological Applications 12(5): 1418-1433.     • Cattle Grazing and the Loss of Biodiversity in the East Bay .      • Livestock Grazing, Fire Regimes, and Tree Densities: A Literature Review .

    • Frogs . In Bernheimer, K. (ed.), Brothers and Beasts: An Anthology of Men on Fairy Tales. Wayne State University Press. Suckling, K.F., 2007.     • Biodiversity, Linguistic Diversity and Identity — Toward an Ecology of Language in an Age of Extinction . Suckling, K., 2000. Langscape 17: 14-20.     • A House on Fire: Connecting the Biological and Linguistic Diversity Crises . 2002. Animal Law 6: 193-202.

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Extinction and the U.S. Endangered Species Act

Noah greenwald.

1 Center for Biological Diversity, Portland, OR, USA

Kieran F. Suckling

2 Center for Biological Diversity, Tucson, AZ, USA

Brett Hartl

3 Center for Biological Diversity, Washington, DC, USA

Loyal A. Mehrhoff

4 Center for Biological Diversity, Honolulu, HI, USA

Associated Data

The following information was supplied regarding data availability:

The raw data are available in a Supplementary File and include a complete list of the species we identified as extinct or possibly extinct along with all supporting information.

The U.S. Endangered Species Act is one of the strongest laws of any nation for preventing species extinction, but quantifying the Act’s effectiveness has proven difficult. To provide one measure of effectiveness, we identified listed species that have gone extinct and used previously developed methods to update an estimate of the number of species extinctions prevented by the Act. To date, only four species have been confirmed extinct with another 22 possibly extinct following protection. Another 71 listed species are extinct or possibly extinct, but were last seen before protections were enacted, meaning the Act’s protections never had the opportunity to save these species. In contrast, a total of 39 species have been fully recovered, including 23 in the last 10 years. We estimate the Endangered Species Act has prevented the extinction of roughly 291 species since passage in 1973, and has to date saved more than 99% of species under its protection.

Introduction

Passed in 1973, the U.S. Endangered Species Act (ESA) includes strong protections for listed threatened and endangered species and has helped stabilize and recover hundreds of listed species, such as the bald eagle and gray whale ( Taylor, Suckling & Rachlinski, 2005 ; Schwartz, 2008 ; Suckling et al., 2016 ). In part because of its strong protections, the ESA has engendered substantial opposition from industry lobby groups, who perceive the law as threatening their profits and have been effective in generating opposition to species protections among members of the U.S. Congress. One common refrain from opponents of the ESA in Congress and elsewhere is that the law is a failure because only 2% of listed species have been fully recovered and delisted ( Bishop, 2013 ).

The number of delistings, however, is a poor measure of the success of the ESA because most species have not been protected for sufficient time such that they would be expected to have recovered. Suckling et al. (2016) , for example, found that on average listed birds had been protected just 36 years, but their federal recovery plans estimated an average of 63 years for recovery. Short of recovery, a number of studies have found the ESA is effectively stabilizing or improving the status of species, using both biennial status assessments produced by the U.S. Fish and Wildlife Service for Congress and abundance trends ( Male & Bean, 2005 ; Taylor, Suckling & Rachlinski, 2005 ; Gibbs & Currie, 2012 ; Suckling et al., 2016 ).

In addition to recovering species, one of the primary purposes of the ESA is to prevent species extinction. Previous studies indicate the ESA has been successful in this regard ( McMillan & Wilcove, 1994 ; Scott et al., 2006 ). As of 2008, the ESA was estimated to have prevented the extinction of at least 227 species and the number of species delisted due to recovery outnumbered the number of species delisted for extinction by 14–7 ( Scott et al., 2006 ). In this study, we identified all ESA listed species that are extinct or possibly extinct to quantify the number of species for which ESA protections have failed and use these figures to update the estimated number of species extinctions prevented. This is the first study in over 20 years to compile data on extinction of ESA listed species, providing an important measure of one of the world’s strongest conservation laws ( McMillan & Wilcove, 1994 ).

To identify extinct or possibly extinct ESA listed species, we examined the status of all 1,747 (species, subspecies and distinct population segments) U.S. listed or formerly listed species, excluding species delisted based on a change in taxonomy or new information showing the original listing to have been erroneous. We determined species to be extinct or possibly extinct based on not being observed for at least 10 years, the occurrence of adequate surveys of their habitat, and presence of threats, such as destruction of habitat of the last known location or presence of invasive species known to eliminate the species.

To differentiate extinct and possibly extinct species we relied on determinations by the U.S. Fish and Wildlife Service, IUCN, species experts and other sources. In most cases, these determinations were qualitative rather quantitative. Species were considered extinct if surveys since the last observation were considered sufficient to conclude the species is highly likely to no longer exist, and possibly extinct if surveys were conducted after the last observation, but were not considered sufficient to conclude that extinction is highly likely ( Butchart, Stattersfield & Brooks, 2006 ; Scott et al., 2008 ).

Source information included 5-year reviews, listing rules and critical habitat designations by the U.S. Fish and Wildlife Service (for aquatic and terrestrial species) or NOAA Fisheries (for marine species), published and gray literature, personal communication with species experts and classifications and accounts by NatureServe, IUCN and the Hawaiian Plant Extinction Prevention program. For each species, we identified year of listing, year last seen, NatureServe and IUCN ranking, taxonomic group, and U.S. Fish and Wildlife Service region. For species last seen after listing, we also searched for abundance estimates at time of listing in order to give a sense of likelihood of survival regardless of ESA protection.

Following previously developed methods, we estimated the number of species extinctions prevented by the ESA by assuming that listed threatened and endangered species have a comparable extinction risk to IUCN endangered species, which was estimated as an average of 67% over 100 years ( Mace, 1995 ; Schwartz, 1999 ; Scott et al., 2006 ). We believe this estimate of extinction risk is conservative based on similarity of IUCN criteria to factors considered in ESA listings, observed low numbers for species at time of ESA listing and observed correspondence between ESA listed species and species classified as endangered or critically endangered by the IUCN ( Wilcove, McMillan & Winston, 1993 ; Wilcove & Master, 2005 ; Harris et al., 2012 ). Presumed extinction risk was then multiplied by the number of extant listed species and the proportion of a century in which species were protected by the ESA. Previous studies used the length of time the ESA has been in existence (1973-present) for the proportion of a century species have been protected ( Schwartz, 1999 ; Scott et al., 2006 ), but because many species have not been protected the entire 45 years the law has existed, we instead used the more conservative average length species were protected (25 years). This corresponds to the following formula:

We identified a total of 97 ESA listed species that are extinct (23) or possibly extinct (74). Of these, we found 71 extinct (19) or possibly extinct (52) species were last observed before they were listed under the ESA and thus are not relevant to determining the Act’s success in preventing extinction ( Table S1 ). These species were last seen an average of 24 years before protection was granted with a range of one to more than 80 years prior.

A total of 26 species were last seen after listing, of which four are confirmed extinct and 22 are possibly extinct ( Table S2 ). On average, these species were last seen 13 years after listing with a range of 2–23 years. We were able to find an abundance estimate at the time of listing for 19 of these species, ranging from one individual to more than 2,000 with an average of 272. In several cases, these estimates were based on extrapolations from very few sightings.

The distribution of extinct and possibly extinct species was non-random with 64 of the 97 species from Hawaii and other Pacific Islands, followed by 18 from the southeast ( Fig. 1 ). This was also the case for taxonomy. A total of 40 of the 97 species were mollusks dominated by Hawaiian tree snails and southeast mussels, followed by birds (18) and plants (17) ( Fig. 2 ).

Extinct or possibly extinct listed species by taxonomic group.

Extinct or possibly extinct listed species by U.S. Fish and Wildlife Service Region.

We identified several other species that have been missing for more than 10 years, but for which there has not been any effective surveys and thus classifying them as possibly extinct did not seem appropriate, including two Hawaiian yellow-faced bees ( Hylaeus facilis and Hylaeus hilaris ) (K. Magnacca, 2018, personal communication) and Fosberg’s love grass ( Eragrostis fosbergii ) ( U.S. Fish and Wildlife Service, 2011 ). If indeed extinct, all three were lost prior to protection under the ESA.

Including updated figures for number of listed species, time of protection and species extinctions, we estimate the ESA has prevented the extinction of roughly 291 species in its 45 year history. Based on the number of confirmed extinctions following listing, we further estimate that the ESA has to date prevented the extinction of more than 99% of species under its protection. To date, a total of 39 species have been delisted for recovery compared to four species that are extinct and 22 that are potentially extinct.

The few number of listed species that have gone extinct following protection combined with an estimated 291 species for which extinction was prevented demonstrate the ESA has achieved one of its core purposes—halting the loss of species. We will not attempt to catalog them here, but numerous individual examples provide further support for this conclusion. Well known species like the California condor ( Gymnogyps californianus ), black-footed ferret ( Mustela nigripes ) and Hawaiian monk seal ( Neomonachus schauinslandi ), as well as lesser known species like the yellowfin madtom ( Noturus flavipinnis ), are but a few of the species that likely would have been lost were it not for the ESA.

The madtom is a case in point. Wrongly presumed extinct when described in 1969, individual madtom were found in the Powell River in Tennessee and Copper Creek in Virginia and the species was protected under the ESA in 1977 ( U.S. Fish and Wildlife Service, 1977 ). Following protection, federal and state officials worked with a non-governmental organization, Conservation Fisheries Inc., to discover additional populations and repatriate the species to rivers and streams in its historic range and there are now populations of the yellowfin madtom in three different watersheds ( U.S. Fish and Wildlife Service, 2012a ). The history of the ESA is replete with similar such stories.

The distribution of extinct or possibly extinct listed species largely tracks those regions with the highest rates of species endangerment, including Hawaii and the Northern Mariana Islands with 64 of the 97 extinctions or possible extinctions, and the Southeast with 18 of the extinctions or possible extinctions, mostly freshwater species. The fragility of Hawaii’s endemic fauna to introduced species and habitat destruction and high degree of species imperilment is well recognized ( Duffy & Kraus, 2006 ). Similarly, the extinction and endangerment of freshwater fauna in the southeast is well documented ( Benz & Collins, 1997 ). To avoid further extinctions, these areas should be priorities for increased funding and effort.

Protection under the ESA came too late for the 71 species last seen prior to listing. It’s possible that some of these species survived undetected following listing, but we find this unlikely for most if not all of the species. It is very difficult to document extinction, but all of the species were the subject of survey both before and after listing, which is described in the listing rules and subsequent status surveys. In addition, the 71 species were last seen an average of 24 years prior to listing, providing a long window for detection prior to listing. If some of these species did survive after listing it was likely at very low numbers, such that recovery would have been difficult at best.

That these 71 species were lost before protections were applied clearly highlights the need to move quickly to protect species. Indeed, Suckling, Slack & Nowicki (2004) identified 42 species that went extinct while under consideration for protection. Since that analysis was completed, the U.S. Fish and Wildlife Service has determined five additional species did not qualify for protection because they were extinct, including the Tacoma pocket gopher ( Thomomys mazama tacomensis ), Tatum Cave beetle ( Pseudanophthalmus parvus ), Stephan’s riffle beetle ( Heterelmis stephani), beaverpond marstonia ( Marstonia castor ) and Ozark pyrg ( Marstonia ozarkensis ), meaning there are now 47 species that have gone extinct waiting for protection ( U.S. Fish and Wildlife Service, 2012b , 2016 , 2017 , 2018a ).

The U.S. Fish and Wildlife Service currently faces a backlog of more than 500 species that have been determined to potentially warrant protection, but which await a decision ( U.S. Fish and Wildlife Service, 2018b ). Under the ESA, decisions about protection for species are supposed to take 2 years, but on average it has taken the Fish and Wildlife Service 12 years ( Puckett, Kesler & Greenwald, 2016 ). Such lengthy wait times are certain to result in loss of further species and run counter to the purpose of the statute. This problem can be addressed by streamlining the Service’s process for listing species, which has become increasingly cumbersome, and by increasing funding for the listing program. For every species listed, the Service’s process includes review by upward of 20 people, including numerous individuals who have no specific knowledge of the species and in a number of cases are political appointees. We instead recommend that the Service adopt a process similar to scientific peer review, involving review by two to three qualified individuals.

The loss of 26 species after they were protected is indicative of conservation failure. This failure, however, in most cases cannot be wholly attributed to the ESA because most of these species were reduced to very low numbers by the time they were protected, making recovery difficult to impossible. Of the 19 species we could find an abundance estimate for at the time of listing, 13 had an estimated population fewer than 100 with eight having fewer than 10 individuals. Of the six other species, two Hawaiian birds, Oahu creeper ( Paroreomyza maculate ) and ‘O’u ( Psittirostra psittacea ) had estimated populations in the hundreds, but this was based on sightings of single individuals. Given the lack of further sightings and the presence of disease carrying mosquitoes throughout their habitat, these estimates were likely optimistic. The other four species, the dusky seaside sparrow ( Ammodramus maritimus nigrescens ), Morro Bay kangaroo rat ( Dipodomys heermanni morroensis ), pamakani ( Tetramolopium capillare ) and Curtis’ pearlymussel ( Epioblasma florentina curtisii ), had populations at the time of listing ranging from 100 to 3,000 individuals, but sufficient action was not taken to save them, making them true conservation failures.

At some level, all of the 97 ESA listed species that we identified as possibly extinct or extinct are conservation failures. For 42 of these species, the law itself was too late because they were last seen before the ESA was passed in 1973. But for others, there may have been time and we did not act quickly enough or dedicate sufficient resources to saving them. There are many examples of species both in the U.S. and internationally that have been successfully recovered even after dropping to very small numbers, but this can only occur with fast, effective action, resources and in many cases luck. The Mauritius kestrel ( Falco punctatus) , for example, was brought back from just two pairs ( Cade & Jones, 1993 ) and the Hawaiian plant extinction prevention program, which focuses on saving plants with fewer than 50 individuals, has rediscovered many species believed extinct, brought 177 species into cultivation, constructed fences to protect species from non-native predators and reintroduced many species into the wild ( Wood, 2012 , http://www.pepphi.org/ ).

The failure to provide sufficient resources for conservation of listed species, however, continues to the present. As many as 27 species of Oahu tree snail ( achatinella spp. ) are extinct or possibly extinct, yet expenditures for the species that still survive are inadequate to support minimal survey and captive propagation efforts. Likewise, the Hawaiian plant extinction prevention program, which has been so effective in saving species on the brink of extinction, is facing a budget cut of roughly 70% in 2019 ( http://www.pepphi.org/ ), which very likely could mean the extinction of dozens of plants that otherwise could be saved. Overall, Greenwald et al. (2016) estimate current recovery funding is roughly 3% of estimated recovery costs from federal recovery plans. We can save species from extinction, but it must be more of a priority for federal spending. Nevertheless, despite funding shortfalls and the tragedy of these species having gone extinct, the ESA has succeeded in preventing the extinction of the vast majority of listed species and in this regard is a success.

Management implications

Of the 97 species we identified as extinct or potentially extinct, only 11 have been delisted for extinction. Another 11 have been recommended for delisting due to extinction. The San Marcos gambusia ( Gambusia georgei ) could also be delisted since there is very little hope it survives. For the other 74 possibly extinct species, we recommend retaining protections in the hope that some will be rediscovered and because there is little cost in retaining listing.

Supplemental Information

Supplemental information 1.

Extinct or possibly extinct species broken out by whether last seen before or after protection was enacted, including relevant source data and literature cited.

Funding Statement

The authors received no funding for this work.

Additional Information and Declarations

All authors are employed by the Center for Biological Diversity which works to protect endangered species and their habitats.

Noah Greenwald conceived and designed the experiments, performed the experiments, analyzed the data, prepared figures and/or tables, authored or reviewed drafts of the paper, approved the final draft.

Kieran F. Suckling conceived and designed the experiments, performed the experiments, analyzed the data, authored or reviewed drafts of the paper, approved the final draft.

Brett Hartl conceived and designed the experiments, performed the experiments, analyzed the data, authored or reviewed drafts of the paper, approved the final draft.

Loyal A. Mehrhoff conceived and designed the experiments, performed the experiments, analyzed the data, authored or reviewed drafts of the paper, approved the final draft.

Endangered and Threatened Species of the Platte River (2005)

Chapter: 8 conclusions and recommendations, 8 conclusions and recommendatons.

I n the previous chapters, the Committee on Endangered and Threatened Species in the Platte River Basin has explored science and its application for policy on the central and lower Platte River. The committee presents here its responses to the series of questions (reviewed in Box 1-2 ) included in its charge. In this chapter, for each question, we state our conclusions and the primary sources of evidence leading to them.

To reach its conclusions, the committee considered the extent of the data available for each question and whether the data was generated according to standard scientific methods that included, where feasible, empirical testing. The committee also considered whether those methods were sufficiently documented and whether and to what extent they had been replicated, whether either the data or the methods used had been published and subject to public comment or been formally peer-reviewed, whether the data were consistent with accepted understanding of how the systems function, and whether they were explained by a coherent theory or model of the system. To assess the scientific validity of the methods used to develop instream-flow recommendations, the committee applied the criteria listed above, but focused more directly on the methods. For example, the committee considered whether the methods used were in wide use or generally accepted in the relevant field and whether sources of potential error in the methods have been or can be identified and the extent of potential error estimated. The committee acknowledges that no one of the above criteria is decisive, but taken together they provide a good sense of the extent to

which any conclusion or decision is supported by science. Because some of the decisions in question were made many years ago, the committee felt that it was important to ask whether they were supported by the existing science at the time they were made. For that purpose, the committee asked, in addition to the questions above, whether the decision makers had access to and made use of state-of-the-art knowledge at the time of the decision.

The population viability analysis (PVA) developed by the committee was constrained by the short study period. It did not include systematic sensitivity analyses and did not base stochastic processes and environmental variation on data from the Platte River region. A more thorough representation of environmental variation in the Platte River could be developed from regional records of climate, hydrology, disturbance events, and other stochastic environmental factors. Where records on the Platte River basin itself are not adequate, longer records on adjacent basins could be correlated with records on the Platte to develop a defensible assessment of environmental variation and stochastic processes. In addition, a sensitivity analysis could demonstrate the effects of wide ranges of environmental variation on the outcomes of PVAs. In its analysis, the committee did not consider methods and techniques that are under development by researchers such as the new SEDVEG model. SEDVEG is being developed, but is not yet completed or tested, by USBR to evaluate the interactions among hydrology, river hydraulics, sediment transport, and vegetation for application on the Platte River. The committee did not consider USGS’s in-progress evaluation of the models and data used by USFWS to set flow recommendations for whooping cranes. The committee did not consider any aspects of the Environmental Impact Statement that was being drafted by U.S. Department of the Interior (DOI) agencies related to species recovery, because it was released after the committee finished its deliberations. The Central Platte River recovery implementation program proposed in the cooperative agreement by the Governance Committee also was not evaluated, because it was specifically excluded from the committee’s charge.

The committee’s experience with data, models, and explanations led us to the identification of three common threads throughout the issues related to threatened and endangered species. First, change across space and through time is pervasive in all natural and human systems in the central and lower Platte River. Change implies that unforeseen events may affect the survival or recovery of federally listed species. Land-use and water-use changes are likely in the central and lower Platte River region in response to market conditions, changing lifestyles, shifts in the local human population, and climate change; such changes will bring about pressures on wildlife populations that are different from those observed today. For example, riparian vegetation on the central Platte River has changed because of both natural and anthropogenic impacts. Regardless of its condition and

distribution before European settlement in the middle 1800s, the riparian forest of the central Platte River was geographically limited from the middle 1800s to the first decades of the 1900s. At the time of the first aerial photography of the river in 1938, extensive sandbars, beaches, and braided channels without extensive forest cover were common in many reaches of the central Platte. Between the late 1930s and the middle to late 1960s, woodland covered increasing portions of the areas that had previously been without trees. By the late 1990s, clearing of woodlands had become a major habitat-management strategy to benefit whooping cranes that desire open roosting areas with long sight lines. Whooping cranes have used the newly cleared areas, but the overall effects of clearing on the crane population and on the structure of the river are not completely known. As with most habitat-management strategies in the central Platte River, there has been no specific monitoring to assess the success of clearing. Unintended effects remain to be investigated.

From a planning and management perspective, stable conditions are desirable so that prediction of outcomes of decisions can be simplified; but stability is rare, especially in the Platte River Basin. Explanations of existing hydrological, geomorphologic, and biological conditions and predictions of future conditions that fail to discern and accommodate change are not likely to be successful. Science can inform decision makers about expected outcomes of various choices, but prediction of the outcomes is likely to be imprecise because of ecosystem variability. Management choices therefore must include some flexibility to deal with the inevitable variability and must be adaptive, continually monitoring and adjusting. The conditions our parents would have seen in these ecosystems a half-century ago were not the conditions we see now, and present conditions are not likely to be the ones our children or grandchildren will see.

A second thread identified by the committee is that one’s view of an ecosystem depends on the temporal and spatial scales on which it is examined. The variability in scale of processes in smaller drainage basins nested within larger ones is obvious, but most natural systems have a similar nested hierarchical structure. The groups of birds and fish that use the Platte River Basin are a fraction of the larger, more widely distributed population, so conditions along the river affect only a portion of each population at any time. Loss of the subpopulations that use the Platte River might not damage the entire population if there were no losses elsewhere—something that Platte River managers cannot assume. The concentration of listed species along the central Platte indicates the importance of the river, despite the fact that the birds can be found elsewhere in Nebraska during migration or nesting periods. The river is important from a management perspective because it contains all the habitat features that are included in the regulatory definitions of critical habitat.

The river supplies the needs of an assemblage of species in addition to serving the needs of single species.

Climate also operates on a series of hierarchical scales. Regional climate in the central and northern Great Plains evinces a variety of changes that depend on the time scale used for analysis. Over a period of 5 or even 10 years, we do not see the complete range of temperature and rainfall conditions likely to be experienced over a century. Decades-long drought or wet periods are likely to be important in species survival and recovery, so short-term observations of less than a few years cannot illuminate the expected conditions that a recovery effort must face.

The various scales of scientific analysis with respect to threatened and endangered species in the Platte River Basin imply that decisions based on science should also recognize scale. Decisions concerning the Platte River Basin that are based on short-term multiyear data and a local perspective are not likely to benefit the long-term (multidecadal) viability of a species that operates on a continental or intercontinental scale. The costs of efforts to recover threatened or endangered species are often most obvious on a local scale, but the benefits are much more widely distributed.

The third thread is that water links the needs of human, wildlife, and habitat more than any other ecological process. Many of the risks to threatened and endangered species, and all the comprehensive solutions to the problem of recovery, require a refined understanding of hydrological processes. The hydrological system of the Platte River is highly interconnected, so solutions to the species issues that attempt to protect commodity values of water must also be interconnected, particularly between surface water and groundwater. Climatic changes create a changing backdrop for the more important human-induced changes in the hydrology of the basin. The committee is firmly convinced that upstream storage, diversion, and distribution of the river’s flow are the most important drivers of change that adversely affect species habitat along the Platte River.

COMMITTEE’S FINDINGS

1. Do current central Platte habitat conditions affect the likelihood of survival of the whooping crane? Do they limit (adversely affect) its recovery?

Conclusions: The committee concluded that, given available knowledge, current central Platte habitat conditions adversely affect the likelihood of survival of the whooping crane, but to an unknown degree. The Platte River is important to whooping cranes: about 7% of the total whooping crane population stop on the central Platte River in any one year, and many, if not all, cranes stop over on the central Platte at some point in their lifetimes. Population viability analyses show that if mortality were to

increase by only 3%, the general population would likely become unstable. Thus, if the cranes using the Platte River were eliminated, population-wide effects would be likely. Resources acquired by whooping cranes during migratory stopovers contribute substantially to meeting nutrient needs and probably to ensuring survival and reproductive success. Because as much as 80% of crane mortality appears to occur during migration, and because the Platte River is in a central location for the birds’ migration, the river takes on considerable importance. The committee concluded that current habitat conditions depend on river management in the central Platte River, but the population also depends on events in other areas along the migratory corridor. If habitat conditions on the central Platte River—that is, the physical circumstances and food resources required by cranes—decline substantially, recovery could be slowed or reversed. The Platte River is a consistent source of relatively well-watered habitat for whooping cranes, with its water source in distant mountain watersheds that are not subject to drought cycles that are as severe as those of the Northern Plains. There are no equally useful habitats for whooping cranes nearby: the Rainwater Basin dries completely about once a decade, and the Sandhills are inconsistent as crane habitat, while the Niobrara and other local streams are subject to the same variability as the surrounding plains. Future climatic changes may exacerbate conflicts between habitat availability and management and human land use. If the quality or quantity of other important habitats becomes less available to whooping cranes, the importance of the central Platte River could increase.

Primary Sources of Scientific Information: The basis of the above conclusion is published documents that were available to other researchers and the public including the original listing document and recovery plan for the species and a review of knowledge about the cranes by the Interstate Task Force on Endangered Species (EA Engineering, Science and Technology, Inc. 1985). Other important contributions to knowledge include Allen (1952) and Austin and Richert (2001). The committee also reviewed and discussed critical comments presented in open sessions and written testimony exemplified by Lingle (G. Lingle, unpublished material, March 22, 2000) and Czaplewski et al. (M.M. Czaplewski et al., Central Platte Natural Resource District, unpublished material, August 22, 2003) that was critical of the research conducted by DOI agencies.

2. Is the current designation of central Platte River habitat as “critical habitat” for the whooping crane supported by existing science?

Conclusions: An estimated 7% of the wild, migratory whooping crane population now uses the central Platte River on an annual basis and many, if not all, cranes stop over on the central Platte at some point in their

lifetimes. The proportion of whooping cranes that use the central Platte River and the amount of time that they use it are increasing (with expected inter-annual variation). The designation of central Platte River migratory stopover habitat as critical to the species is therefore supported because the birds have specific requirements for roosting areas that include open grassy or sandy areas with few trees, separation from predators by water, and proximity to foraging areas such as wetlands or agricultural areas. The Platte River critical habitat area is the only area in Nebraska that satisfies these needs on a consistent basis. However, some habitats designated as critical in 1978 appear to be largely unused by whooping cranes in recent years, and the birds are using adjacent habitats that are not so designated (Stehn 2003).

Habitat selection (to the extent that it can be measured) on multiple geographic scales strongly suggests that Nebraska provides important habitat for whooping cranes during their spring migration. Riverine, palustrine, and wetland habitats serve as important foraging and roosting sites for whooping cranes that stop over on the central Platte River. Whooping cranes appear to be using parts of the central Platte River that have little woodland and long, open vistas, including such areas outside the zone classified as critical habitat. In some cases the cranes appear to be using areas that have been cleared of riparian woodland, perhaps partly explaining their distribution outside the critical habitat area.

Primary Sources of Scientific Information: The basis of the committee’s conclusion is published documents that were available to other researchers and the public including the original listing document, recovery plan, and declaration of critical habitat; and information in Howe (1989) and Austin and Richert (2001). The committee also considered commentary that was critical of the research conducted by DOI agencies exemplified by open sessions and written testimony presented by Lingle (G. Lingle, unpublished material, March 22, 2000), EA Engineering, Science and Technology, Inc. (1985) and Czaplewski et al. (M.M. Czaplewski et al., Central Platte Natural Resources District, unpublished material, August 22, 2003).

3. Do current central Platte habitat conditions affect the likelihood of survival of the piping plover? Do they limit (adversely affect) its recovery?

Conclusions: Reliable data indicate that the northern Great Plains population of the piping plover declined by 15% from 1991 to 2001. The census population in Nebraska declined by 25% during the same period. Resident piping plovers have been virtually eliminated from natural riverine habitat on the central Platte River. No recruitment (addition of new individuals to the population by reproduction) has occurred there since 1999. The

disappearance of the piping plover on the central Platte can be attributed to harassment caused by human activities, increased predation of nests, and losses of suitable habitat due to the encroachment of vegetation on previously unvegetated shorelines and gravel bars.

The committee concluded that current central Platte River habitat conditions adversely affect the likelihood of survival of the piping plover, and, on the basis of available understanding, those conditions have adversely affected the recovery of the piping plover. Changes in habitat along the river—including reductions in open, sandy areas that are not subject to flooding during crucial nesting periods—have been documented through aerial photography since the late 1930s and probably have adversely affected populations of the piping plover. Sandpits and reservoir edges with beaches may, under some circumstances, mitigate the reduction in riverine habitat areas. Because piping plovers are mobile and able to find alternative nesting sites, changes in habitat may not be as severe as they would be otherwise, but no studies have been conducted to support or reject this hypothesis.

Primary Sources of Scientific Information: Corn and Armbruster (1993) demonstrated differences (including higher river invertebrate densities and catch rates) in foraging habitat between the river and sand pit sites; this suggests that riverine habitat areas are superior to the sand mines and reservoir beaches for the piping plover. Basic information sources include the listing document and recovery plan. Higgins and Brashier (1993) provide additional information on habitat conditions, survival, and recovery. The committee also considered commentary presented in open sessions and written testimony exemplified by Lingle (G. Lingle, unpublished material, March 22, 2000) and Czaplewski et al . (M.M. Czaplewski et al., Central Platte Natural Resources District, unpublished material, August 22, 2003) that was critical of the research conducted by DOI agencies.

4. Is the current designation of central Platte River habitat as “critical habitat” for the piping plover supported by the existing science?

Conclusions: The designation of central Platte habitat as critical habitat for the piping plover is scientifically supportable. Until the last several years, the central Platte supported substantial suitable habitat for the piping plover, including all “primary constituent elements” required for successful reproduction by the species. Accordingly, the central Platte River contributed an average of more than 2 dozen nesting pairs of plovers to the average of more than 100 pairs that nested each year in the Platte River Basin during the 1980s and 1990s. The critical habitat designation for the species explicitly recognizes that not all areas so designated will provide all neces-

sary resources in all years and be continuously suitable for the species. It is also now understood that off-stream sand mines and reservoir beaches are not an adequate substitute for natural riverine habitat.

Primary Sources of Scientific Information: Data generated according to standard scientific methods in well-defined and well-executed scientific investigations support the critical habitat designation for the piping plover—including work by Ziewitz et al. (1992), Ducey (1983), and Faanes (1983)—as does the designation in the Federal Register (67:57638 [2002]). The committee also considered commentary presented in open sessions and written testimony exemplified by Lingle (G. Lingle, unpublished material, March 22, 2000) and Czaplewski et al. (M.M. Czaplewski et al., Central Platte Natural Resources District, unpublished materials, August 10, 2001, and August 22, 2003) that was critical of the research conducted by DOI agencies.

5. Do current central Platte habitat conditions affect the likelihood of survival of the interior least tern? Do they limit (adversely affect) its recovery?

Conclusions: The committee concluded that current habitat conditions on the central Platte River adversely affect the likelihood of survival of the interior least tern—in much the same fashion as they affect the likelihood of survival of the piping plover—and that on the basis of available information, current habitat conditions on the central Platte River adversely affect the likelihood of recovery of the interior least tern. Reliable population estimates indicate that the total (regional) population of interior least terns was at the recovery goal of 7,000 in 1995, but some breeding areas, including the central Platte River, were not at identified recovery levels. The central Platte subpopulation of least terns declined from 1991 to 2001. The number of terns using the Platte River is about two-thirds of the number needed to reach the interior least tern recovery goal for the Platte. The interior tern is nesting in substantial numbers on the adjacent lower Platte River, but numbers continue to decline on the central Platte, reflecting declining habitat conditions there. The decline in the tern population on the central Platte River has been coincidental with the loss of numerous bare sandbars and beaches along the river. Control of flows and diversion of water from the channel are the causes of these geomorphic changes. Woodland vegetation, unsuitable as tern habitat, has colonized some parts of the central Platte River. Alternative habitats, such as abandoned sand mines or sandy shores of Lake McConaughy, are not suitable substitutes for Platte River habitat because they are susceptible to disturbance by humans and natural predators. The shores of Lake McConaughy are available only at lower stages of the reservoir, and they disappear at high stages.

Primary Sources of Scientific Information: The scientific underpinnings of these conclusions are extensive and substantial, including work by Smith and Renken (1990), Sidle and Kirsch (1993), Ziewitz et al. (1992), and Higgins and Brashier (1993), all of whom used sound, widely accepted, standard scientific methods. The committee also considered commentary presented in open sessions and written testimony exemplified by Lingle (G. Lingle, unpublished material, March 22, 2000) and Czaplewski et al. (M.M. Czaplewski et al., Central Platte Natural Resources District, unpublished material, August 22, 2003) that was critical of the research conducted by DOI agencies.

6. Do current habitat conditions in the lower Platte (below the mouth of the Elkhorn River) affect the likelihood of survival of the pallid sturgeon? Do they limit (adversely affect) its recovery?

Conclusions: Current habitat conditions on the lower Platte River (downstream of the mouth of the Elkhorn River) do not adversely affect the likelihood of survival and recovery of the pallid sturgeon because that reach of the river appears to retain several habitat characteristics apparently preferred by the species: a braided channel of shifting sandbars and islands; a sandy substrate; relatively warm, turbid waters; and a flow regime that is similar to conditions that were found in the upper Missouri River and its tributaries before the installation of large dams on the Missouri. Alterations of discharge patterns or channel features that modify those characteristics might irreparably alter this habitat for pallid sturgeon use. In addition, the lower Platte River is connected with a long undammed reach of the Missouri River, which allows access of the pallid sturgeon in the Platte River to other segments of the existing population. Channelization and damming of the Missouri River have depleted pallid sturgeon habitats throughout its former range, so the lower Platte may be even more important for its survival and recovery. The population of pallid sturgeon is so low in numbers, and habitat such as the lower Platte River that replicates the original undisturbed habitat of the species is so rare that the lower Platte River is pivotal in the management and recovery of the species.

Primary Sources of Scientific Information: Scientific studies supporting those conclusions are reported in numerous peer-reviewed publications, as exemplified by general research on the habitat of hatchery-derived pallid sturgeon in the lower Platte River by Snook (2001) and Snook et al. (2002). Carlson et al. (1985) and Kallemeyn (1983) provided useful background information. Additional investigations in the Missouri River system by Bramblett (1996) and Bramblett and White (2001) have results that are applicable to the lower Platte River. The committee also considered com-

mentary presented in open sessions and written testimony exemplified by Czaplewski et al. (M.M. Czaplewski et al., Central Platte Natural Resources District, unpublished material, August 22, 2003) that was critical of the research conducted by DOI agencies.

7. Were the processes and methodologies used by the USFWS in developing its central Platte River instream-flow recommendations (i.e., species, annual pulse flows, and peak flows) scientifically valid?

Conclusions: The U.S. Fish and Wildlife Service (USFWS) used methods described in an extensive body of scientific and engineering literature. Reports of interagency working groups that addressed instream-flow recommendations cite more than 80 references that were in wide use and generally accepted in the river science and engineering community. The committee reviewed that information, as well as oral and written testimony critical of the research conducted by DOI agencies, and it concluded that the methods used during the calculations in the early 1990s were the most widely accepted at that time. Revisions were made as improved knowledge became available. Although the Instream Flow Incremental Method (IFIM) and Physical Habitat Simulation System (PHABSIM) were the best available science when DOI agencies reached their recommendations regarding instream flows, there are newer developments and approaches, and they should be internalized in DOI’s decision processes for determining instream flows. The new approaches, centered on the river as an ecosystem rather than focused on individual species, are embodied in the concepts of the normative flow regime. Continued credibility of DOI instream-flow recommendations will depend on including the new approach.

The instream-flow recommendations rely on empirical and model-based approaches. Surveyed cross sections along the river provided DOI investigators with specific information on the morphology of the river and vegetation associated with the river’s landforms. The portions of the cross sections likely to be inundated by flows of various depths were directly observed. Model calculations to simulate the dynamic interaction of water, geomorphology, and vegetation that formed habitat for species were handled with the prevailing standard software PHABSIM, which has seen wide use in other cases and has been accepted by the scientific community. The software was used by DOI researchers in a specific standard method, IFIM, which permits observations of the results as flow depths are incrementally increased.

The continuing DOI model developments, including the emerging SEDVEG model, are needed because of the braided, complex nature of the Platte River—a configuration that is unlike other streams to which existing models are often applied. The committee did not assess the newer models,

because they have not yet been completed or tested, but it recommends that they be explored for their ability to improve decision making.

The committee also recognizes that there has been no substantial testing of the predictions resulting from DOI’s previous modeling work, 1 and it recommends that calibration of the models be improved. Monitoring of the effects of recommended flows should be built into a continuing program of adaptive management to help to determine whether the recommendations are valid and to indicate further adjustments to the recommendations based on observations.

Primary Sources of Scientific Information: The literature used to support USFWS’s methods ranged from basic textbook sources, such as Dunne and Leopold (1978) and Darby and Simon (1999), to specific applications exemplified by Simons & Associates, Inc. (2000) and Schumm (1998). The committee also considered the interagency working reports (Hydrology Work Group 1989; M. Zallen, DOI, unpublished memo, August 11, 1994) and oral and written testimony exemplified by Parsons (2003), Payne (1995; T.R. Payne and Associates, pers. comm., June 19, 2003), Woodward (2003), and Lewis (2003).

8. Are the characteristics described in the USFWS habitat suitability guidelines for the central Platte River supported by the existing science and are they (i.e., the habitat characteristics) essential to the survival of the listed avian species? To the recovery of those species? Are there other Platte River habitats that provide the same values that are essential to the survival of the listed avian species and their recovery?

Conclusions: The committee concluded that the habitat characteristics described in USFWS’s habitat suitability guidelines for the central Platte River were supported by the science of the time of the original habitat description during the 1970s and 1980s and were consistent with accepted understanding of how the systems function. New ecological knowledge has since been developed. The new knowledge, largely from information gathered over the last 20 years, has not been systematically applied to the processes of designating or revising critical habitat, and the committee recommends that it be done.

The committee also concluded that suitable habitat characteristics along the central Platte River are essential to the survival and recovery of the piping plover and the interior least tern. No alternative habitat exists in the

central Platte that provides the same values essential to the survival and recovery of piping plovers and least terns. Although both species use artificial habitat (such as shoreline areas of Lake McConaughy and sandpits), the quality and availability of sites are unpredictable from year to year. The committee further concluded that suitable habitat for the whooping crane along the central Platte River is essential for its survival and recovery because such alternatives as the Rainwater Basin and other, smaller rivers are used only intermittently, are not dependable from one year to the next, and appear to be inferior to habitats offered by the central Platte River.

Primary Sources of Scientific Information: The committee relied on the following sources in reaching its conclusions: for whooping cranes, the original listing document, recovery plan, and declaration of critical habitat and Howe (1989), EA Engineering, Science and Technology, Inc. (1985), Austin and Richert (2001), and Lutey (2002); for interior least terns and piping plovers, the original listing documents, recovery plans, and declaration of critical habitat for the piping plover (Fed. Regist. 67 (176): 57638 [2002]), Smith and Renken (1990), Sidle and Kirsch (1993), Ziewitz et al. (1992), Ducey (1983), Faanes (1983), Higgins and Brashier (1993), Corn and Armbruster (1993), and Kirsch and Sidle (1999). The committee also considered commentary presented in open sessions and written testimony exemplified by Lingle (G. Lingle, unpublished material, March 22, 2000) and Czaplewski et al. (M.M. Czaplewski et al., Central Platte Natural Resources District, unpublished material, August 22, 2003) that was critical of the research conducted by DOI agencies.

9. Are the conclusions of the Department of the Interior about the interrelationships of sediment, flow, vegetation, and channel morphology in the central Platte River supported by the existing science?

Conclusions: The committee concluded that DOI conclusions about the interrelationships among sediment, flow, vegetation, and channel morphology in the central Platte River were supported by scientific theory, engineering practice, and data available at the time of those decisions. By the early 1990s, when DOI was reaching its conclusions, the community of geomorphologists concerned with dryland rivers had a general understanding of the role of fluctuating discharges in arranging the land forms of the channel, and DOI included this understanding in its conclusions about the river. In the early 1990s, engineering practice, combined with geomorphology and hydrology, commonly used IFIM and PHABSIM to make predictions and recommendations for flow patterns that shaped channels, and this resulted in adjustments in vegetation and habitat. In fact, despite some criticisms, IFIM and PHABSIM are still widely used in the professional

community of river restorationists in 2004. In applying scientific theory and engineering practice, the DOI agencies used the most current data and made additional measurements to bolster the calculations and recommendations. Since the early 1990s, more data have become available, and the USBR has conducted considerable cutting-edge research on a new model (SEDVEG) that should update earlier calculations but is not yet in full operation (and was not reviewed by this committee).

Primary Sources of Scientific Information: Murphy et al. (2001) outline the basic understanding of sediment and vegetation dynamics. Sediment data are obtained by sampling sediment concentrations and multiplying the concentrations by discharges and duration. For flow, gaging records on the Platte River are 50 years in duration or longer, and they are in greater density than on many American rivers; the gages provide quality data on water discharge for the Platte River. Murphy and Randle (2003) review the analyses and other sources of knowledge about the flows that provide a sound basis for DOI decisions. In addition to the review by Murphy et al. (2001) concerning vegetation, several studies over the last 20 years have provided an explanation of vegetation dynamics that the committee found to be correct and that is the basis of DOI decisions. Early work by USFWS (1981a) and Currier (1982) set the stage for an evolution of understanding of vegetation change on the river that was later expanded by Johnson (1994). For channel morphology, there is a long history of widely respected research to draw on, including early geomorphologic investigations by Williams (1978) and Eschner et al. (1983), continuing with the reviews by Simons and Associates (2000), and culminating in recent work by Murphy and Randle (2003). The committee also considered commentary presented in open sessions and written testimony exemplified by Parsons (2003) and Lewis (2003) that was critical of the research conducted by DOI agencies.

10. What were the key information and data gaps that the NAS identified in the review?

Conclusions: The committee reached its conclusions for the preceding nine questions with reasonable confidence based on the scientific evidence available. However, the committee identified the following gaps in key information related to threatened and endangered species on the central and lower Platte River, and it recommends that they be addressed to provide improved scientific support for decision making.

A multiple-species perspective is missing from research and management of threatened and endangered species on the central and lower Platte River. The interactions of the protected species with each other and with

unprotected species are poorly known. Efforts to enhance one species may be detrimental to another species, but these connections remain largely unknown because research has been focused on single species. One approach is to shift from the focus on single species to an ecosystem perspective that emphasizes the integration of biotic and abiotic processes supporting a natural assemblage of species and habitats.

There is no systemwide, integrated operation plan or data-collection plan for the combined hydrological system in the North Platte, South Platte, and central Platte Rivers that can inform researchers and managers on issues that underlie threatened and endangered species conservation. Natural and engineered variations in flows in one part of the basin have unknown effects on other parts of the basin, especially with respect to reservoir storage, groundwater storage, and river flows.

A lack of a full understanding of the geographic extent of the populations of imperiled species that inhabit the central Platte River and a lack of reliable information on their population sizes and dynamics limit our ability to use demographic models to predict accurately their fates under different land-management and water-use scenarios. Detailed population viability analyses using the most recent data would improve understanding of the dynamics of the populations of at-risk species and would allow managers to explore a variety of options to learn about the probable outcomes of decisions. Continuation of population monitoring of at-risk bird species using the best available techniques, including color-banding of prefledged chicks and application of new telemetry techniques, is recommended.

There is no larger regional context for the central and lower Platte River in research and management. Most of the research and decision making regarding threatened and endangered species in the Platte River Basin have restricted analysis to the basin itself, as though species used its habitats in isolation from other habitats outside the basin. There are substantial gaps in integrative scientific understanding of the connections between species that use the habitats of the central and lower Platte River and adjacent habitat areas, such as the Rainwater Basin of southern Nebraska and the Loup, Elkhorn, and Niobrara Rivers and other smaller northern Great Plains rivers.

The committee is confident that the central Platte River and lower Platte River are essential for the survival and recovery of the listed bird species and pallid sturgeon. However, in light of the habitat it provides and the perilously low numbers of the species, there is not enough information to assess the exact degree to which the Platte contributes to their survival and recovery.

Water-quality data are not integrated into knowledge about species responses to reservoir and groundwater management and are not integrated

into habitat suitability guidelines. Different waters are not necessarily equal, either from a human or a wildlife perspective, but there is little integration of water-quality data with physical or biological understanding of the habitats along the Platte River.

The cost effectiveness of conservation actions related to threatened and endangered species on the central and lower Platte River is not well known. Neither the cost effectiveness nor the equitable allocation of measures for the benefit of Platte River species has been evaluated. The ESA does not impose or allow the implementing agencies to impose a cost-benefit test. Listed species must be protected no matter what the cost, unless the Endangered Species Committee grants an exemption. Cost effectiveness, however, is another matter. The ESA permits consideration of relative costs and benefits when choosing recovery actions, for example. USFWS has adopted a policy that calls for minimizing the social and economic costs of recovery actions, that is, of choosing actions that will provide the greatest benefit to the species at the lowest societal cost (Fed. Regist. 59:3472 [1994]). In addition, persons asked to make economic sacrifices for the sake of listed species understandably want assurances that their efforts will provide some tangible benefit. In the Platte, the direct economic costs of measures taken for the benefit of species appear reasonably well understood. The biological benefits are another matter. For example, the costs of channel-clearing and other river-restoration measures are readily estimated. Their precise value for cranes is more difficult to estimate, although their general use is fairly well established.

The allocation of conservation costs and responsibility also has not been systematically evaluated. USFWS has concentrated its efforts to protect listed species in the Platte system on federal actions, such as the operation of federal water projects. That focus is understandable. Water projects with a federal nexus account for a large and highly visible proportion of diversions from the system. In addition, those actions may be more readily susceptible to regulatory control than others because they are subject to ESA Section 7 consultation. But some nonfederal actions also affect the species. Water users that depend on irrigation water from the federal projects may well feel that they are being asked to bear an inordinate proportion of the costs of recovering the system. A systematic inventory of all actions contributing to the decline of the species could help the parties to the cooperative agreement channel their recovery efforts efficiently and equitably. The National Research Council committee charged with evaluating ESA actions in the Klamath River Basin recently reached a similar conclusion (NRC 2004a).

The effects of prescribed flows on river morphology and riparian vegetation have not been assessed. Adaptive-management principles require that the outcomes of a management strategy be assessed and monitored and

that the strategy be adjusted accordingly, but there has been no reporting of the outcomes of the 2002 prescribed flow, no analysis of vegetation effects of managed flows, no measurement of their geomorphic effects, and no assessment of their economic costs or benefits.

The connections between surface water and groundwater are not well accounted for in research or decision making for the central and lower Platte River. The dynamics of and connections between surface water and groundwater remain poorly known, but they are important for understanding river behavior and economic development that uses the groundwater resource. The effects of groundwater pumping, recently accelerated, are unknown but important for understanding river flows.

Some of the basic facts of issues regarding threatened and endangered species in the central and lower Platte River are in dispute because of unequal access to research sites. Free access to all data sources is a basic tenet of sound science, but DOI agencies and Nebraska corporations managing water and electric power do not enter discussions about threatened and endangered species on the central and lower Platte River with the same datasets for species and physical environmental characteristics. USFWS personnel are not permitted to collect data on some privately owned lands. As a result, there are substantial gaps between data used by DOI and data used by the companies, and resolution is impossible without improved cooperation and equal access to measurement sites.

Important environmental factors are not being monitored. Monitoring, consistent from time to time and place to place, supports good science and good decision making, but monitoring of many aspects of the issues regarding threatened and endangered species on the central and lower Platte River remains haphazard or absent. Important gaps in knowledge result from a lack of adequate monitoring of sediment mobility, the pallid sturgeon population, and movement of listed birds. Responses of channel morphology and vegetation communities to prescribed flows and vegetation removal remain poorly known because the same set of river cross sections is not sampled repeatedly. Groundwater may play an important role in flows, but groundwater pumping is not monitored.

Long-term (multidecadal) analysis of climatic influences has not been used to generate a basis for interpretation of short-term change (change over just a few years). The exact interactions between climate and the system are poorly known because only short-term analyses of climate factors have been accomplished so far. In addition, the relative importance of human and climatic controls remains to be explicitly defined by researchers, even though such knowledge is important in planning river restoration for habitat purposes.

Direct human influences are likely to be much more important than climate in determining conditions for the threatened and endangered species

of the central and lower Platte River. Potentially important localized controls on habitat for threatened and endangered species on the central and lower Platte River are likely to be related to urbanization, particularly near freeway exits and small cities and towns where housing is replacing other land uses more useful to the species. Off-road vehicle use threatens the nesting sites of piping plovers and interior least terns in many of the sandy reaches of the river. Sandy beaches and bars are inviting to both birds and recreationists. Illegal harvesting has unknown effects on the small remaining population of pallid sturgeon. In each of those cases, additional data are required to define the threats to the listed species.

USFWS faces extraordinary challenges in trying to identify the habitat needs and the critical habitat for listed species on the central and lower Platte River. Lack of data, pressures of tight deadlines for research, lack of a well-defined adaptive-management strategy with effective monitoring, and competing uses for the river’s water and landscape resources complicate decision making. Despite those challenges, the science that explains forms and processes of the ecosystems along the central and lower Platte River of Nebraska is sufficient to support many decisions about the management of threatened and endangered species that use the river’s habitats. In all cases, enough is known about the physical environmental processes that control habitat change to make informed decisions for the survival of the whooping crane, piping plover, interior least tern, and pallid sturgeon. Our scientific knowledge is not yet adequate to contribute to decisions regarding the exact role of the central and lower Platte River in the recovery of the whooping crane and pallid sturgeon. Valid science supports critical habitat designations for the piping plover, but the scientific support of critical habitat designation for the whooping crane is weak. Valid science and engineering related to hydrology, geomorphology, sediment transport, and riparian ecology support the DOI instream-flow recommendations and explanations for the river-channel and vegetation changes. The committee found numerous gaps in knowledge that could inform management of threatened and endangered species along the central and lower Platte River, mostly focused on problems of scientific integration, overrestricted scales of analysis, lack of systemwide connections, and lack of standardized procedures for data collection.

Land, water, and life in the region surrounding the 100th meridian on the Platte River are highly changeable and precariously balanced. Human manipulations of hydrological conditions and land cover have far-reaching consequences for wildlife populations. Policy based on a desired constant, stable, and predictable set of environmental circumstances is unlikely to be

successful. Policy that relies on scientific knowledge about change through time and over geographic space is the most likely avenue to success in the search for accommodation between economic vitality and diverse and sustainable populations of wildlife that are neither threatened nor endangered.

The tension between wildlife protection under the Endangered Species Act and water management in the Platte River Basin has existed for more than 25 years. The Platte River provides important habitat for migratory and breeding birds, including three endangered or threatened species: the whooping crane, the northern Great Plains population of the piping plover, and the interior least tern. The leading factors attributed to the decline of the cranes are historical overhunting and widespread habitat destruction and, for the plovers and terns, human interference during nesting and the loss of riverine nesting sites in open sandy areas that have been replaced with woodlands, sand and gravel mines, housing, and roadways. Extensive damming has disrupted passage of the endangered pallid sturgeon and resulted in less suitable habitat conditions such as cooler stream flows, less turbid waters, and inconsistent flow regimes. Commercial harvesting, now illegal, also contributed to the decline of the sturgeon.

Endangered and Threatened Species of the Platte River addresses the habitat requirements for these federally protected species. The book further examines the scientific aspects of the U.S. Fish and Wildlife Service’s instream-flow recommendations and habitat suitability guidelines and assesses the science concerning the connections among the physical systems of the river as they relate to species’ habitats.

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Environmental Studies: Saving Endangered Species Essay

There is no secret that in the present-day world, hundreds of species vanish from the face of the Earth completely due to the changes in their habitat. The latter, being spawned by the environmental changes inflicted by people’s activities, requires thorough research. One of the major concerns of the XXI century, the shrinkage of the Atlantic Forest, will inevitably trigger the disappearance of an even greater number of species populations.

To make the matters worse, some of the endangered species in question are nowhere else to be found except for the Atlantic Forest, which means that these animals and plants will be lost for good for the humankind (Mongillo & Zierdt-Warsaw, 2000). With the help of modern technologies, such as Google Earth, one can detect the source of the problem and, therefore, provide an efficient solution to it.

The procedure for acquiring the necessary data is relatively easy. By using the Google Earth Plug-in (Google Planet), one starts the program on the PC, either going to the 3-D model or remaining in the Google Earth view. Below is the image of Rio de Janeiro:

When reconsidering the evidence obtained via Google Earth, one must admit that the given method of acquiring information also has its flaws, the most basic one being the inability to locate the effects that the civilization has on nature. Google Earth shows the total area of the Atlantic Forest in a very graphic way:

The second picture shows that the deforested areas in Rio de Janeiro are increasing rapidly. For instance, the area used for growing coffee crops has shrunken considerably, which can be observed in the picture above. When speaking about deforested tropical areas, one must also mention the coast of Rio and its industrial regions:

In addition, it is relatively easy to spot the line drawn between the natural habitat and the environment created by people:

However, the effect of the latter on the Atlantic Forest is practically unnoticeable in Google Earth. One might argue, however, that by comparing the evidence obtained before the current evidence, one can spot the tendency in Atlantic Forest shrinkage.

According to the existing evidence, creating an artificial environment that will resemble the one in the Atlantic Forest is practically impossible. Due to the specifics of the local climate, as well as the environment, which every single element of a tropical rainforest, starting with a mosquito to the huge, centennial trees, contributes considerably to.

Therefore, the most reasonable solution to the given problem is not to create an artificial environment, but to restore and sustain the Atlantic Forest, making sure that each of its elements is in its place and that people have no effect on its fragile ecosystem.

One of the most efficient solutions for saving the Atlantic Forest species from dying out is to follow the principles of sustainability. Despite the considerable distance between the location and civilization of the rainforests, it is necessary to admit that people’s intrusion into the rainforest ecosystem occurs daily. One of the major problems concerning the relationship between people and nature in this regard is the process of cutting rainforests down.

On the one hand, the process of cutting trees down is inevitable – people need to use natural resources to create the environment in which they can live, i.e., build houses, create furniture and household appliances, not to mention people’s need in paper as one of the integral parts of people’s everyday life.

On the other hand, with the current technological advances, several rainforests could be saved if people used not only wood, but also other materials for furniture, paper, and other life essentials (Palo & Vanhanen, 2000). As the snapshots above show, the areas that used to be the realm of tropical rainforests have been replaced by blocks of flats, numerous hotels, and other buildings. While technological progress must be appreciated, it should not come at the cost of rainforests and the unique nature of the Atlantic Forest.

Considering the areas in question closer, one must admit that the number of rainforests in Rio is dropping quickly. It seems that the city makes almost 80% of the land, which used to be the place where rainforests grew.

Also, if comparing some of the images in the center of the city and some of its remote corners, one will inevitably find out that the amount of rainforests is narrowing down by at least 2% per year. The given phenomenon can be explained by the rapid process of urbanization and the tendency to occupy the entire area of the city with economically valuable objects, ie, offices, hotels, and houses for rent (Gay, 2001).

Therefore, it can be assumed that the endangered species can still be saved. By analyzing the situation with the help of the Google Earth software, one can make sure that the animals and plants inhabiting tropical rainforests will be safe. Also, it is worth keeping in mind that the tropical rainforests also need people’s care and protection from the impact of civilization. That being said, it can be assumed that the tropical life, though being under threat, still can be saved.

Reference List

Gay, K. (2001). Rainforests of the world: A reference book . Santa-Barbara, CA: ABC-CLIO.

Mongillo, J. F. & Zierdt-Warsaw, L. (2000). Encyclopedia of environmental science . Phoenix, AZ: The Oryx Press.

Palo, M. & Vanhanen, H. (2000). World forests: From deforestation to transition? Norwell, MA: Kluwer Academic Publishers.

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• Chicago (N-B)

IvyPanda. (2020, March 19). Environmental Studies: Saving Endangered Species. https://ivypanda.com/essays/environmental-studies-saving-endangered-species/

"Environmental Studies: Saving Endangered Species." IvyPanda , 19 Mar. 2020, ivypanda.com/essays/environmental-studies-saving-endangered-species/.

IvyPanda . (2020) 'Environmental Studies: Saving Endangered Species'. 19 March.

IvyPanda . 2020. "Environmental Studies: Saving Endangered Species." March 19, 2020. https://ivypanda.com/essays/environmental-studies-saving-endangered-species/.

1. IvyPanda . "Environmental Studies: Saving Endangered Species." March 19, 2020. https://ivypanda.com/essays/environmental-studies-saving-endangered-species/.

Bibliography

IvyPanda . "Environmental Studies: Saving Endangered Species." March 19, 2020. https://ivypanda.com/essays/environmental-studies-saving-endangered-species/.

• Biodiversity Conservation: Tropical Rainforest
• Deforestation and Its Man-Made Causes
• Deforestation Problem
• Banning Hosepipe Use as a Poor Solution to a Water Shortage
• Environmental Hazards in Working in a Nail Salon
• Natural Sciences: How Do Animals Become Extinct?
• E-Waste Causes and Effects
• Hydraulic Fracking for Natural Gas Extraction in Pennsylvania

Protecting threatened and endangered species in a changing climate

Sydney Giuliano

Service scientists are truly superheroes, protecting our wild spaces and saving species from extinction. To make these daring rescues, they first need to know what they’re up against. 

While our heroes don’t have the power to see into the future, with the help of climate models, they’re protecting wildlife and plants like the whitebark pine from future harm.

The power of the ESA 

The Endangered Species Act is incredibly effective, saving 99% of listed species from extinction. It protects listed species from actions that may lead to their death or harm, including direct actions like poaching and indirect actions like destruction of the habitats these species call home. 

But what does it mean to make the list? 

Under the ESA, species may be listed as threatened or endangered. Endangered means a species is likely to completely disappear or go extinct in the near future. Threatened means a species is likely to become endangered in the near future.

So, as the planet warms, how do scientists project potential changes in the landscape and how species will respond? 

They use models that gather information from around the world on trends in greenhouse gas emissions, human population-growth and development, and more to determine a range of likely future conditions. 

Species-specific

Dotting mountainsides along ranges such as the Sierras and Rockies, majestic, crown-shaped whitebark pine trees grow 16 to 66 feet tall. Whitebark pine is a keystone or foundational species, meaning its existence is necessary to maintain the health of its environment and the species that live there. These evergreens stabilize soil, slow snow-melt, reduce flooding and provide food for many seed-eating animals. They typically thrive in cold, windy forests at high elevations and are known to live for 500 to 1,000 years. 

But in December 2022, the Service listed whitebark pine as a threatened species, in part because of how climate change climate change Climate change includes both global warming driven by human-induced emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. Though there have been previous periods of climatic change, since the mid-20th century humans have had an unprecedented impact on Earth's climate system and caused change on a global scale. Learn more about climate change is expected to impact its habitat. 

For all ESA listings, Service scientists compile the best available information on the species’ characteristics, life history and habitat. Then they look at the current condition of the species, including its abundance, range and genetic variation. 

Current population health, genetic make-up and range all influence whether the species as a whole can withstand changes in its environment. More populations and a larger range allow for certain populations or areas to experience losses without the species as a whole disappearing. However, genetic variability that helps account for adaptive responses to changing conditions may be lost; the genetic difference between one tree and the next may be the reason why one tree survives stressors like disease and another does not. 

Service Endangered Species Biologist Dr. Brenna Forester explained, “Service biologists are continually learning and adapting to new information, so the best-available scientific information is used to inform ESA decisions."

When looking at listing whitebark pine, scientists first considered the tree’s reproductive cycle and decided they should model for 180 years, or three generations, rather than the 75-year standard for most climate-change modeling. By looking at generations rather than years, they can better understand how the species will respond to change over time. 

Model projections show scientists how whitebark pine habitat may change in those 180 years. Combined with the data on current status, this insight informs listing decisions.

Where does this information come from? 

Climate change is one of the greatest environmental stressors we face today. To better understand the challenges wildlife and plants will have to overcome, our scientists look at information gathered globally. 

The Service relies on the Intergovernmental Panel on Climate Change, created by the United Nations in 1988. The IPCC provides governments with information on what is causing climate change, how this change will impact our planet, the future risks associated with this change, and how these risks can be reduced. They gather the best available science from around the world, and regional experts from different global regions review the information to make sure it’s objective and complete. 

Scientists plug this climate data into models that simulate climate processes, using current trends to make projections about future changes. 

For example, scientists know the world’s oceans are warming by 0.27°F per decade because they have been measuring ocean temperatures for more than a century. A climate model can use that information to project ocean temperatures 50 or 100 years from now. 

These models can also help us account for uncertainties that might change projected outcomes, like how quickly and effectively the world reduces global greenhouse gas emissions and how the climate system responds to those reductions. These climate scenarios help us compare how climate conditions may change depending on things like population growth, economic growth and changes in technology. 

Global models can be downscaled to look at unique locations with specific features — like the Gulf of Maine, which is warming faster than the rest of the world’s oceans — to understand how landscape features, like hills and river valleys, change local climate patterns.

“Models can be simple or complex depending on how much information we have,” Dr. Forester said. “In either case, they are critical to ensuring a clear, transparent, and repeatable approach to assessing extinction risk.”

A lifetime of needs

When evaluating a species for listing, we identify its needs for all life stages. Whitebark pine seeds need cold weather to start to grow, but mature trees need two summers of warmer temperatures and enough rain to mature. From there, scientists dive deeper into the habitat and resources a species relies on to better understand how potential changes at a location may have a domino effect on the species in question. 

Whitebark pine has multiple stressors that could influence its survival, including diseases such as white pine blister rust, which damages stems and cone-bearing branches and restricts nutrient flow until the tree eventually dies. Models project that within 10 to 20 years all whitebark pine trees will be infected with white pine blister rust.

Additionally, mountain pine beetles have been attacking these trees in record numbers — the trees’ only defense is low winter temperatures that can kill beetle larvae and adults. At their high elevation, whitebark pines used to be protected. But as winters shorten and temperatures rise, mountain pine beetles are now thriving at higher and higher elevations. The safe areas for whitebark pines are shrinking.

Fortunately for the trees, Clark’s nutcrackers might swoop in and save them. These crow-like birds have specialized beaks to extract seeds from whitebark pinecones. The nutcrackers carry the seeds for miles before storing them — effectively planting them in the ground. 

But the relationship between the birds and the trees is not equal. Clark’s nutcrackers can also extract seeds from other pine species. With food available elsewhere, it’s highly likely that, as temperatures increase, Clark’s nutcrackers will move to cooler areas, leaving whitebark pine trees behind with no way to migrate. 

How accurate are these models? 

Humans are uniquely able to change the world at both local and global scales. Our actions as individuals and as a species are unpredictable. This is why we model scenarios that consider a range of potential human choices. 

Because humans can change on a whim, we can only lay out probable scenarios; we can’t determine which are more likely to happen. 

However, we do have confidence that the scenarios we currently use accurately project future conditions up to the year 2100 for most climate change information. How, might you ask?

When people think about climate change, they often consider it a future problem, yet right now we are experiencing the results of a changing climate, including an increase in extreme weather events, sea-level rise, droughts and wildfires.

Climate models have produced accurate hindcasts of climate change in the last century. In a hindcast, a model is tested by comparing its results to see if they match actual historical records. The success of these tests gives us confidence that the models will continue to accurately project the effects of climate change. 

Climate and conservation 

Climate models help us determine not only which species need immediate protection but also what actions are necessary to protect them. Modeling helps scientists weigh restoration projects based on their likelihood of success. The models combine all the existing knowledge to determine what locations and actions will lead to the best results.

For whitebark pines, it’s not as simple as helping those populations under the most stress. In an area with trees infected with white pine blister rust, for example, newly planted seedlings would likely die off quickly. A population with fewer stressors, on the other hand, may benefit from planting trees. 

Meanwhile, that same disease-stressed population could contain individual trees with a genetic advantage for surviving the rust. Rather than planting more trees, we could do more for that population and the species by conducting genetic studies to look for and propagate rust-resistant trees. 

Looking ahead

In 2023, we celebrated the 50th anniversary of the Endangered Species Act. As a scientific community, the Service and its partners have come a long way from the decision-making of the past. 

“I have hope because of the 50 years of conservation successes under the ESA,” Dr. Forester said. “The ESA is one of the most powerful and effective environmental laws in the world. One of the major reasons it has been so successful is the incredibly talented and dedicated scientists and policy experts who work for the U.S. Fish and Wildlife Service. We all work together to continually innovate and improve how we apply science and policy to protect species from extinction — something which is needed now more than ever.”

Advances in technology like climate modeling help these dedicated individuals break down the extremely complex questions of which species need protection and how we can best protect them.

Though we can’t see into the future, it is clear, with the continued advancement of technology and the commitment of our super scientists across the country, the next 50 years of the Endangered Species Act will be full of success stories and, most importantly, hope. 

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The Kiwi Makes a Startling but Careful Comeback

At a sanctuary on New Zealand’s North Island, the long-endangered flightless birds have grown so much in number that they are being transported to other areas to start new colonies.

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By Pete McKenzie

The Australia Letter is a weekly newsletter from our Australia bureau. This week’s issue is written by Pete McKenzie, a reporter based in Auckland, New Zealand.

Capturing a kiwi is more challenging than I expected. Despite standing just two feet tall, an adult bird is armed with pistonlike legs and razor-sharp claws. And, according to Will Kahu, a ranger with the conservation group Save the Kiwi, “They’re surprisingly feisty.”

He recalled one standoff that ended with a kiwi leaping through the air, kicking him in the chest and sprinting off while he tumbled to the ground.

Which is how I found myself squatting safely atop a fallen tree in Sanctuary Mountain Maungatautari, a fenced-in nature reserve on New Zealand’s North Island, while Mr. Kahu and several volunteers extracted a bird from its burrow in the rotting trunk beneath me.

“One leg, two legs — got it,” Dave Laithwaite, a volunteer at the sanctuary, said while groping around in the mud in the kiwi’s narrow den. He pulled the writhing bird out, then calmed it by cradling it like a baby.

The kiwi, New Zealand’s national bird, has seen a resurgence in numbers thanks to conservation efforts. In 2005, several kiwis were placed in the Maungatautari sanctuary in a last-ditch effort to prevent them from being hunted to extinction by predators like stoats and ferrets.

Now, more than 2,500 of the fiercely territorial birds live on Sanctuary Mountain, which is quickly running out of space for them. To relieve the pressure, conservationists caught and exported 209 kiwis to new homes across the country last week.

“It’s the biggest kiwi translocation ever,” Mr. Kahu said.

“My feeling is of celebration,” said Bodie Taylor, a representative of an Indigenous tribe that helps run Sanctuary Mountain. “To hear them tangi” — cry — “and see them running free, it opens your heart.”

Most remarkable is the way these flightless birds are being moved: by plane.

After the hunt, I drove to Waikato Airport behind a van full of squeaking birds.

“We’re here for the Sanctuary Mountain flight,” Steven Cox, a conservation ranger, said to an airport receptionist when we arrived.

The receptionist asked what the cargo was.

“Kiwi,” Mr. Cox said. The receptionist said she’d call over her manager.

Outside, two planes from an aeronautics club in Wellington, New Zealand’s capital, taxied across a runway. Conservationists prefer to transport kiwis by plane when relocating them across long distances to minimize travel time and stress on the birds.

“It’s pretty cool,” Kai Furst-Jaeger, the pilot, said as he helped load the birds onto the planes. “I didn’t think I’d get to handle kiwi in my lifetime.”

There were once 12 million kiwis in New Zealand, but the species was devastated after humans introduced predators like ferrets, rats and stoats. In areas with predators, less than 10 percent of hatchlings survive six months. Roughly 70,000 birds belonging to five species remain, mostly in fenced-in reserves or on remote islands.

But intensive efforts by government rangers, volunteer trappers and conservationists at refuges like Sanctuary Mountain have propelled the growth of some kiwi species. The species at Sanctuary Mountain, the North Island brown kiwi, is expected to see its population increase by 10 percent over the next three generations.

That is allowing conservationists to take risks: the birds from Sanctuary Mountain are going to reserves that are not fenced in. While trapping has eliminated most predators at these reserves, the kiwis there still face dangers.

“We know some kiwi may die in the wild, but we have to build large populations with resilience,” said Michelle Bird, a coordinator for Save The Kiwi. “We’re looking at the population level.”

I hopped into an aircraft packed with six birds. As we rattled down the runway, I cast a worried eye at the crates.

“It must be a weird experience for them,” I said.

“Yeah, I hear flying isn’t their strong suit,” Chris Forbes, the pilot, joked. He told me he laughed when Wellington Aero Club asked for volunteers to help flightless kiwis soar.

We flew between the snow-capped mountains of Ruapehu and Taranaki, then followed the coastline past Kapiti Island to Wellington. Below us lay sprawling fields with occasional towns and roadways: a landscape that has changed dramatically since kiwis roamed freely several centuries ago, when much of the land was native forest.

“I’ve heard no squawks from the kiwi,” Mr. Forbes said as we approached Wellington.

“I suppose that’s a good sign,” I replied.

We touched down smoothly, then pulled into a warehouse where half a dozen volunteers were waiting. Within minutes, the crates were loaded into several cars and on their way to the city’s western edge, where the conservation group Capital Kiwi has spent five years establishing a predator-free zone. After being reintroduced into the area in 2022, the kiwi bred there for the first time in living memory.

Now, Sanctuary Mountain has sent 100 of the birds to the area to supercharge Wellington’s growing kiwi population. As night fell, we unloaded the crates at the Karori Golf Course, which lies at the foot of the predator-free area. At the last hole, a tribal representative released a kiwi into a stand of native bush. As the kiwi scurried away, a native owl hooted in the starlight.

“It provides hope,” Ms. Bird said of the kiwi transfer. “And hope is important.”

Here are this week’s stories.

Australia and New Zealand

The Hard Road to ‘Furiosa’ Was Filled With Detours . For George Miller, Anya Taylor-Joy and their crew, a series of natural disasters made for an arduous production.

Alarmed by Climate Change, Astronomers Train Their Sights on Earth . In Australia and elsewhere, a growing number of researchers are using their expertise to fight the crisis.

The Unusual Evolutionary Journey of the Baobab Tree . New research shows the “upside-down trees” originated in Madagascar and then caught a ride on ocean currents to reach mainland Africa and Australia.

Around The Times

As Russia Advances, NATO Considers Sending Trainers Into Ukraine . The move could draw the United States and Europe more directly into the war. The Biden administration continues to say there will be no American troops on the ground.

Dancing Past the Venus de Milo . The Louvre is joining in the celebration of the Paris Olympics by opening up for dance and exercise classes early in the morning.

At a Supreme Court Justice’s House, a ‘Stop the Steal’ Symbol on Display. An upside-down U.S. flag, adopted by Trump supporters contesting President Biden’s victory, flew over Justice Samuel Alito’s front lawn in 2021 as the court was considering an election case.

Slovakia’s Politics Were Toxic Long Before Its Prime Minister Was Shot . Years of vitriolic rhetoric, worsened by the Covid-19 pandemic and the war in Ukraine, left Slovakia with bitter political division.

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