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Monday, February 14, 2011

Gray Wolves Under the Endangered Species Act: Distinct Population Segments and Experimental Populations

Kristina Alexander
Legislative Attorney

M. Lynne Corn
Specialist in Natural Resources Policy

The wolf was among the first animals protected under the Endangered Species Preservation Act, a predecessor to the current Endangered Species Act of 1973 (ESA). In 1978 the gray wolf was listed as endangered in all of the conterminous 48 states except Minnesota, where it was listed as threatened. With the exception of experimental populations established in the 1990s, the protections for the gray wolf have been diminishing since that date, as wolf populations have increased in some areas—primarily in the Northern Rocky Mountains, but not in the Southwest. The use of distinct population segments (DPSs), a term created in the 1978 ESA amendments, has played a role in that reduced protection. DPSs allow vertebrate species to be divided into distinct groups, based on geography and genetic distinctions. This report analyzes the DPS designation process as it is applied to the gray wolf. It also examines experimental populations of wolves under the ESA and their protections.

ESA protection for wolf DPSs has changed back and forth since the first DPSs—Western and Eastern—were proposed in 2003. Each effort by FWS to delist the wolf or designate a DPS has been rejected by a court. In 2004, the U.S. Fish and Wildlife Service (FWS) determined that because of the population size, those DPSs no longer needed the protection of the ESA and so were delisted. The Western and Eastern DPS designations and delistings were nullified by courts. In 2007, FWS designated and delisted the Western Great Lakes DPS, and in early 2008, FWS designated and delisted the Northern Rocky Mountains DPS. However, courts found both delistings flawed and vacated both rulemakings. In December 2008 FWS returned the wolves in the Western Great Lakes and parts of the Northern Rocky Mountains areas to their former protected status, eliminating the DPSs. That same rulemaking redesignated wolves in southern Montana, southern Idaho, and all of Wyoming as “nonessential experimental populations,” which they were prior to the DPS efforts. In April 2009 FWS published notices establishing DPSs in the Western Great Lakes and the Northern Rockies and delisting both populations except for in Wyoming. FWS was sued regarding the Western Great Lakes delisting and settled the case, returning the population to its previous status (threatened and endangered). A court held in August 2010 that the Northern Rockies delisting violated the ESA, directing that the delisting be declared invalid. The Northern Rockies wolves were returned to their experimental population status, meaning they are treated as threatened in most circumstances.

The 112
th Congress responded to court nullification of the regulatory delistings by introducing legislation to eliminate all protections of the gray wolf nationwide under the ESA (H.R. 509— Rehberg; S. 249—Hatch), and to let states decide how to protect wolves found in Idaho and Montana (H.R. 510—Rehberg). If passed, they would be the first examples of Congress removing protections for a specific species under the ESA. The 111th Congress also had proposed legislation to restrict protection of the wolf. Three House bills would have reduced or eliminated ESA protections of the gray wolf: H.R. 6028 (Edwards—Texas), H.R. 6485 (Bishop—Utah), and H.R. 6486 (Bishop—Utah). Two Senate bills took more regional approaches addressing wolves in the Northwest: S. 3825 (Risch), and S. 3864 (Baucus).

Date of Report: February 3, 2011
Number of Pages: 21
Order Number: RL34238
Price: $29.95

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