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, 7, e6803

Extinction and the U.S. Endangered Species Act


Extinction and the U.S. Endangered Species Act

Noah Greenwald et al. PeerJ.


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.

Keywords: Endangered species; Extinction; Species recovery; U.S. Endangered Species Act.

Conflict of interest statement

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


Figure 1
Figure 1. Extinction and taxonomic group.
Extinct or possibly extinct listed species by taxonomic group.
Figure 2
Figure 2. Extinctions by region.
Extinct or possibly extinct listed species by U.S. Fish and Wildlife Service Region.

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Grant support

The authors received no funding for this work.

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