Press Release
Recovery of America’s Smallest Tern Prompts Proposal to Delist

When the interior least tern was listed under the Endangered Species Act (ESA) in 1985, there were fewer than 2,000 birds and only a few dozen nesting sites scattered across a once-expansive range that covered America’s Great Plains and Lower Mississippi Valley. Today there are more than 18,000 interior least terns at more than 480 nesting sites in 18 states, thanks to decades of innovative conservation efforts and diverse partnerships among local, state and federal stakeholders.

A thorough review of the best available science indicates that interior least tern populations are healthy, stable and increasing, and the species no longer faces the threat of extinction. Consequently, the U.S. Fish and Wildlife Service is proposing to delist the species from the ESA due to recovery.

“The recovery of the interior least tern is truly an American conservation success story,” said Margaret Everson, Principal Deputy Director of the Service. “Dozens of states, federal agencies, Tribes, businesses and conservation groups all pitched in to prevent the tern’s extinction and put it on the path to recovery, thanks to the strength of these partnerships.”

Everson specifically pointed to the partnership between the Service and the U.S. Army Corps of Engineers (Corps) as a reason for the tern’s recovery.

“For more than three decades the Corps has implemented a variety of conservation measures that have improved habitat for interior least terns along some of America’s largest rivers, such as the Missouri and the Mississippi. These actions have been central to the tern’s recovery,” she said.

“Stewardship and partnership are two words that come to mind during this momentous time for both the environment and the interior least tern,” said Maj. Gen. Richard Kaiser, Deputy Chief of Engineers and Deputy Commanding General of the U.S. Army Corps of Engineers. “For over 30 years, we have partnered with the Service to monitor, conserve and recover this endangered species along the Lower Mississippi River. The partnership demonstrates that through collaboration, we can protect and recover an endangered species while continuing to provide critical navigation and flood control benefits to the nation. The Corps is absolutely honored to play a role in a partnership that can serve as a model for the recovery and delisting of other species.”

In 2005, the Corps coordinated a range-wide monitoring event, which confirmed that tern populations were increasing over the previous two decades. The Corps also funded, with the assistance of the Service, the development of a habitat-driven, range-wide population model for the species. This complex model, developed with the American Bird Conservancy, considers interior least tern status and population dynamics with and without continued management at local, regional, and range-wide scales across a 30-year period.

To help ensure the species’ continued success, the Corps, which has jurisdictional authority over much of the interior least tern’s range, has made formal post-delisting monitoring and conservation commitments that encompass about 85 percent of the breeding population.

“I applaud today’s announcement proposing to remove the interior least tern from the endangered species list,” said Senator John Barrasso (R-Wyo.). “Since its listing in 1985, states like Wyoming, Colorado, and Nebraska have worked in good faith with landowners, conservation groups, and the federal government to preserve critical habitat and recover this bird. The Platte River Recovery Implementation Plan played a critical role in this case and I look forward to reauthorizing the program so we can continue to build on the success of the interior least tern’s delisting.”

The tern has also benefited from conservation activities achieved under the Platte River Recovery Implementation Program, such as the restoration and maintenance of nesting habitat along the central Platte River. The program provides water users in Wyoming, Colorado and Nebraska with regulatory certainty and ESA compliance. Conservation partnerships such as this are essential to the recovery of our nation’s imperiled species.

Least terns are the smallest members of the tern family and primarily feed on small fish. They are generally considered seabirds, but several species are also found along rivers, lakes or other wetlands. They nest along more than 2,800 miles of river channel habitat across the Great Plains and the Lower Mississippi Valley and winter in the Caribbean and South America.

States where tern colonies now occur are Montana, North Dakota, South Dakota, Nebraska, Colorado, Iowa, Kansas, Missouri, Illinois, Indiana, Kentucky, New Mexico, Oklahoma, Arkansas, Tennessee, Texas, Louisiana and Mississippi.

In the late 19th and early 20th centuries, least terns were decimated by harvest for their feathers, which were used for making hats. Their nesting habitats were also flooded or degraded by dams and other forms of large river channel engineering during the mid-20th century. Due to the impact of these threats, the bird was listed as endangered under the ESA in 1985 as a distinct population segment of least tern. 

Federal and state agencies and industrial partners have all contributed to the interior least tern’s successful recovery. Depending upon local conditions and needs, active habitat management has included: monitoring, protection of nesting areas, improved water flows, dredge material placement, vegetation and predator control. Many of these beneficial activities have become standard practices and are anticipated to continue after delisting. In addition to post-delisting commitments by the Corps, most states and industries with active management and monitoring roles are expected to continue their actions.

The interior least tern’s five-year review is available here:

The proposed rule and supporting documents, including a draft post-delisting monitoring plan, are available at, Docket Number FWS–R4–ES–2018-0082. The Service will seek public review and comments on the proposed rule and draft monitoring plan.

Comments are requested within 60 days or by 12/23/2019, and will be accepted by mail or electronically at In the Search box, enter the docket number, and then click on the “Comment Now!” button. Please note that submissions merely supporting or opposing a potential delisting, without supporting documentation, will not be considered in making a determination.

Requests for a public hearing should be made in writing to: U.S. Fish and Wildlife Service, Mississippi Field Office, 6578 Dogwood View Parkway, Jackson, MS, 39216 by 12/09/2019.

Story Tags

Endangered and/or Threatened species

Recreational Activities