“The Endangered Species Act is the world’s strongest law protecting animals and plants on the brink of extinction. In fact, 99 percent of species protected under the Act have avoided extinction. For the Center’s third in-depth report on the Act’s efficacy, A Wild Success: A Systematic Review of Bird Recovery Under the Endangered Species Act — the most exhaustive analysis of its kind — we examined how well the Act is recovering species by determining the objective, long-term population trends of all 120 bird species that have been listed as threatened or endangered under the Act since 1967. Drawing on more than 1,800 scientific population surveys, our study used scientifically vetted data points to determine (1) if bird populations increased, decreased or stabilized after being protected by the Act, (2) the magnitude of population changes, (3) whether recovery rates are consistent with rates projected in federal recovery plans, and (4) how endangered birds fared in comparison to more common birds. Twenty-three of the birds we examined had no Endangered Species Act population trend because they likely went extinct prior to being protected, were delisted for reasons not related to population trends, or were protected under the Act for fewer than 10 years. Our trend analyses were based on the remaining 97 species. On average our datasets spanned 83 percent of the time each species was protected by the Act; thus they represent a true picture of the Act’s long-term effect. We found that the Endangered Species Act has been extraordinarily successful in recovering imperiled birds:

• Eighty-five percent of bird populations in the continental United States increased or stabilized while protected by the Act.
• The average population increase was 624 percent.
• Birds from the Pacific Islands (Hawaii, Guam, Palau and the Commonwealth of the Northern Marianna Islands) recovered less robustly, with 61 percent either increased or stabilized.
• On average birds have been protected under the Act for 36 years, but their federal recovery plans estimate they need 63 years to fully recover; thus, few birds were expected to have recovered by 2015.
• Birds are recovering at the rate expected by federal recovery plans.”