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Wednesday, April 6, 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

After near eradication of the gray wolf from the lower 48 states in the first half of the 20th century, the wolf was on the Endangered Species Act’s (ESA’s) first list of endangered species, divided into two subspecies—the Eastern Timberwolf and the northern Rocky Mountain wolf. In 1978 the wolf was listed at the species level (the gray wolf) 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, in which the U.S. Fish and Wildlife Service (FWS) reintroduced wolves to selected areas, protections for the gray wolf have diminished as wolf populations have increased in some areas—such as in the Northern Rocky Mountains. 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.

Experimental populations (Ex Pops) of wolves were reintroduced in three regions in the United States in the 1990s: Central Idaho, Yellowstone, and Blue Range (in Arizona and New Mexico, known as Mexican gray wolves). The Ex Pops in Central Idaho and Yellowstone have grown to over 1,650 wolves as of December 31, 2010, while the Mexican gray wolf population has not surpassed 59 wolves, and as of January 2011 totaled 50.

ESA protection for wolf DPSs has changed back and forth since the first DPSs—Western, Eastern, and Southwestern—were proposed in 2003. Each effort by FWS to delist the wolf or designate a DPS has been rejected by a court. In 2003, FWS determined that because of the population size, the Western and Eastern DPSs no longer needed the protection of the ESA and so those DPSs were downlisted from endangered to threatened. Courts nullified the rulemaking. In 2007, FWS designated and delisted the Western Great Lakes DPS, and in early 2008, FWS designated and delisted the Northern Rocky Mountain DPS. However, courts found both delistings flawed and vacated both rulemakings. In April 2009, FWS again established DPSs in the Western Great Lakes and the Northern Rockies and delisted both populations except for in Wyoming. FWS settled the suit regarding the Western Great Lakes delisting, returning the population to its previous status (threatened and endangered). In August 2010, a court ruled 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 but are endangered outside of the Ex Pop boundaries.

A March 2011 settlement agreement would end lawsuits by the participating plaintiffs about Northern Rocky Mountains DPSs for at least five years, but it depends on the court taking a procedural step first. FWS agreed to issue a new rule designating a DPS in the area and delisting those wolves. In the meantime, Montana and Idaho would manage their wolves, while wolves in Wyoming, Washington, Oregon, and Utah would remain under federal protection.

The 112
th Congress is considering legislation to eliminate all protections of the gray wolf under the ESA (H.R. 509—Rehberg; S. 249—Hatch), to let states decide how to protect wolves found in Idaho and Montana (H.R. 510—Rehberg), to direct FWS to reissue the regulatory delisting of April 2009, making the rule immune from judicial review (H.R. 1, § 1713—Simpson; Senate version § 1709—Tester), or to make that regulatory delisting law (S. 321—Baucus). If passed, a delisting bill appears to be the first law to delist a species under the ESA.

Date of Report: March 23, 2011
Number of Pages: 24
Order Number: RL34238
Price: $29.95

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