Endangered Species Act


The Endangered Species Act (ESA for short) was enacted by Congress in 1973. Under the ESA, the federal government has the responsibility to protect:

  • Endangered Species - species that are likely to become extinct throughout all or a large portion of their range.
  • Threatened Species - species that are likely to become endangered in the near future.
  • Critical habitat - vital to the survival of endangered or threatened species.

The Endangered Species Act has lists of protected plant and animal species both nationally and worldwide. When a species is given ESA protection, it is said to be a "listed" species.

As of October 2009, 1,361 plants and animals in the United States were listed as threatened or endangered. There are many additional species that are currently being evaluated for possible protection under the ESA, and they are called “candidate” species.

Who decides which species get Endangered Species Act protection?

Under the Endangered Species Act, the U.S. Fish and Wildlife Service oversees the listing and protection of all terrestrial animals and plants as well as freshwater fish.  The National Marine Fisheries Service oversees marine fish and wildlife.

How does a species get on the Endangered Species List?

When the U.S. Fish and Wildlife Service or the National Marine Fisheries Service is investigating the health of a species, they look at scientific data collected by local, state and national scientists. 


In order to be listed as a candidate, a species has to be found to qualify for protected status under the Endangered Species Act.

Whether or not a species is listed as endangered or threatened then depends on a number of factors, including the urgency and whether adequate protections exist through other means.

When deciding whether a species should be added to the Endangered Species List, the following criteria are evaluated:

  • Has a large percentage of the species vital habitat been degraded or destroyed?
  • Has the species been over-consumed by commercial, recreational, scientific or educational uses?
  • Is the species threatened by disease or predation?
  • Do current regulations or legislations inadequately protect the species?
  • Are there other manmade factors that threaten the long-term survival of the species?

If scientific research reveals that the answer to one or more of the above questions is yes, then the species can be listed under the Endangered Species Act.

What does Endangered Species Act protection mean?

Once a species becomes listed as "endangered" or "threatened," it receives special protections by the federal government.  Animals are protected from “take” and being traded or sold. A listed plant is protected if on federal property or if federal actions are involved, such as the issuing of a federal permit on private land.

The term "take" is used in the Endangered Species Act to include, "harass, harm, pursue, hunt, shoot, wound, kill trap, capture, or collect, or to attempt to engage in any such conduct." The law also protects against interfering in vital breeding and behavioral activities or degrading critical habitat.

The primary goal of the Endangered Species Act is to make species' populations healthy and vital so they can be delisted from the Endangered Species Act. The U.S. Fish and Wildlife Service and the National Marine Fisheries Service actively invest time and resources to bringing endangered or threatened species back from the brink of extinction.   

Why should we protect Threatened and Endangered species?

The Endangered Species Act is very important, because it saves our native fish, plants and wildlife from going extinct. Once they are gone, they are gone forever and there is no going back. Losing even a single species can have disastrous impacts on the rest of the ecosystem, because the effects will be felt throughout the food chain.

From providing cures to deadly diseases to maintaining natural ecosystems and improving overall quality of life, the benefits of preserving threatened and endangered species are invaluable.


6 Endangered Species Success Stories

Bald Eagle

In the 1960s, a mere 500 bald eagles could be found soaring across America's lower 48 states. Dangerous pesticides and chemicals, released into bald eagle habitats, thinned the shells of their eggs, killing their young. By the late 1960's, only 400 breeding pairs of bald eagles were found in the lower 48 states. The outlook was not good for our national symbol. Thanks to the protections afforded by the Endangered Species Act, bald eagle numbers have rebounded to more than 7,000 breeding pairs of bald eagles today. Captive breeding programs, habitat protection, and a ban on DDT contributed to the successful recovery of this American symbol. The species has made an astounding comeback thanks to the amazing work of American citizens, businesses, scientists and the U.S. government. These diverse groups came together to help protect bald eagles under the authority of the U.S. Endangered Species Act.

Florida Panther

A 1989 census indicated that the Florida panther population had dropped to between 30 to 50 individuals. This decline was the result of habitat loss, degradation and fragmentation. Today, the species population is still below 100 individuals, but without Endangered Species Act protections the panther would likely be extinct. These protections include captive breeding, habitat protection, wildlife underpass construction and the introduction of Texas cougars to prevent inbreeding.

Gray Wolf

Gray wolves once ranged across the entire North American continent. However, as a result of poisoning and trapping by ranchers, farmers and government agents, by the mid-20th century, only a few hundred of the species remained in the entire lower 48 states. Today, thanks to Endangered Species Act protections, more than 2,500 wolves reside in Minnesota, roughly 500 wolves in Wisconsin and Michigan and another 500 individuals in western states. The gray wolf’s success is a result of Endangered Species Act-stimulated efforts such as public education about the species, habitat restoration, wolf introduction into various areas and compensation of ranchers for livestock killed by wolves.

Grizzly Bear

Within the lower 48 states, grizzly bear populations have been reduced to a mere two percent of their former range due to a combination of excessive hunting, conversion of habitat to human uses and fragmentation of habitat caused by such things as extensive networks of logging roads. Grizzly bears were brought under federal management when they were listed under the Endangered Species Act in 1975. At that time fewer than 250 bears occupied the Yellowstone area. Since then, the coordinated efforts of state and federal agencies, conservation organizations and private citizens have increased this population to more than 600 bears. In addition to the Yellowstone grizzlies, approximately 600 bears occupy habitat in the lower 48 states, including portions of Glacier National Park and adjacent areas in Montana and in northern Washington adjacent to the Canadian border.

Peregrine Falcon

A 1964 survey found that peregrine falcons did not inhabit a single cliff in the eastern United States or Canadian maritime provinces. By 1970, a mere 10 to 20 percent of the historical falcon population remained, due to egg and nestling collection, intentional shooting and DDT use. Endangered Species Act protections for the falcon included captive breeding, preventing human disturbances to nesting and protection and enhancement of critical breeding and wintering habitat. As a result, populations are thriving. The species was delisted in 1999 and today there are more than 1,400 breeding pairs of peregrines in North America.

Red-cockaded Woodpecker

Red-Cockaded Woodpecker

In the 1960s, a study predicted that the red-cockaded woodpecker would become extinct due to logging, deforestation and fi re suppression. Fewer than 15,000 of these birds survive in about one percent of its former range. Thanks to the Act, restrictions were placed on habitat destruction and since 1995, more than 500,000 acres of private lands have been enrolled in conservation programs, leading the woodpecker toward recovery.

Endangered Species Day

Endangered Species Day is a day to celebrate endangered species success stories and learn about species still in danger.  Endangered Species Day is held on the 3rd Friday of each May. You can support Endangered Species Day by raising awareness in your community about a local threatened species or by helping to clean up a wildlife refuge or park. Events will be happening around the country, so be on the lookout this coming May!

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