Center for Biological Diversity

For Immediate Release, June 21, 2016

Contact: Collette Adkins, (651) 955-3821,

Analysis: 85 Percent of Continental U.S. Birds Protected by Endangered Species Act
Have Increased or Stabilized Since Being Protected

Recovering Birds Include Interior Least Tern, Great Lakes Piping Plover, Kirtland’s Warbler

WASHINGTON— Eighty-five percent of continental United States birds protected under the Endangered Species Act increased or stabilized their population size since being protected, according to a new report by the Center for Biological Diversity. The average population increase was 624 percent. 

Average Recovery of Birds
Kirtland's warbler
Kirtland's warbler by Joel Trick, USFWS. Photos are available for media use.

A Wild Success: A Systematic Review of Bird Recovery Under the Endangered Species Act is the first-ever study to examine the year-by-year population size of all 120 bird species protected under the Endangered Species Act. Drawing on more than 1,800 scientific population surveys, the analysis concludes that the Act has recovered imperiled birds at the rate and magnitude intended by its congressional creators and administrative overseers.

Among the birds improving in the Midwest are the Great Lakes piping plover (up 295 percent since 1985), the Interior least tern (up 603 percent since 1985) and the Kirtland’s warbler (up 1,077 percent since 1971).

“Thanks to the Endangered Species Act the Midwest has interior least terns, Great Lakes piping plovers and fascinating birds like the Kirtland’s warbler,” said Collette Adkins, a biologist and attorney who works in the Center’s Minneapolis office. “All across the country, we’ve seen that the Endangered Species Act works and works well.”

Key findings of the report:

  • 85 percent of continental U.S. birds increased their population size or stabilized since being protected under the Endangered Species Act.
  • The average population increase was 624 percent.
  • 64 percent of Pacific Island (Hawaii, Guam, Palau and the Commonwealth of the Northern Marianna Islands) birds have increased their population size or stabilized since being protected under the Endangered Species Act. The weaker performance is due to lower funding levels, smaller population sizes at the time of Endangered Species Act listing, and more species being threatened by difficult to manage invasive predators and diseases.
  • Few birds were expected to recover by 2015 because they have been protected under the Act for just 36 years on average, while their federal recovery plans estimate 63 years is needed.
  • Birds are recovering at the rate expected by federal recovery plans.
  • Endangered birds fared much better than unprotected birds, which on average declined 24 percent since 1974. This is because endangered birds are being actively managed, while common birds generally are not.

“The Endangered Species Act hasn’t just helped save America’s most imperiled birds, it’s benefited thousands of other species, people and wild places,” Adkins said.

Among the birds in today’s report:

Great Lakes piping plover — These shorebirds nest on the sand spits of glacially formed sand dunes along the Great Lakes shoreline. By the time they were protected as endangered in 1985, hunting and habitat loss caused by unchecked motorized recreation and development had reduced the subspecies to just 19 nesting pairs. Protections put in place to reduce predation and habitat destruction on its nesting grounds allowed the population to steadily increase to 75 nesting pairs by 2015.

Interior least tern — Before being protected as endangered in 1985, the smallest of the North American terns, which prefers nesting on sandbars along major rivers, had seen its numbers plummet below 2,000 birds due to invasive plants and unnatural changes to water flows caused by dams. Endangered Species Act protections helped their population increase to nearly 14,000 by 2012.

Kirtland’s warbler — By 1971 this small, yellow-chested songbird had declined to only 201 singing males, and two years later it was protected as endangered. Beginning in the mid-1970s, some 180,000 acres of jack pine forest were designated for the warbler’s management, triggering habitat restoration that, coupled with control of invasive brown-headed cowbird populations, spurred a steady growth to more than 2,300 singing males by 2015.

Read more in the report and about other Endangered Species Act successes here.

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 1 million members and online activists dedicated to the protection of endangered species and wild places.

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