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The Mountain-Prairie Region


U.S. Fish and Wildlife Service
134 Union Boulevard
Lakewood, Colorado 80228

July 25, 2001

Contact: Patricia Foulk - 916-414-6566
Terry Ireland, 970-243-6209, x16
Pat Deibert, 307-772-2374, x26
Laura Romin, 801-524-5009, x 142
Lori Nordstrom, 406-449-5225, x208
Sharon Rose, 303-236-7917, x 415


SACRAMENTO, Calif.–The U.S. Fish and Wildlife Service today announced that the yellow-billed cuckoo, a songbird found along rivers and streams, is in such severe decline in 10 western states as to warrant protection under the Endangered Species Act, but the agency’s current workload precludes the proposal of the species for protection at this time.

The yellow-billed cuckoo is a secretive, robin-sized bird that in the western United States breeds in willow and cottonwood forests along rivers and streams. The bird’s most notable features are a long, boldly-patterned black-and-white tail, and an elongated and down-curved bill, which is yellow on the bottom. Its plumage is grayish-brown above and white below. Adults have narrow, yellow eye rings. The bird primarily eats large insects including caterpillars and cicadas as well as the occasional small frog or lizard.

"Few breeding populations of the cuckoo are found in the West and those populations are in decline primarily as a result of destruction of their streamside habitat," said Steve Thompson, acting manager of the Service’s California/Nevada Operations Office. "We believe that current scientific evidence supports Endangered Species Act (ESA) protection for these birds in the West; however, with the funds we have available, other higher priority listings that are already in the queue must come first."

Yellow-billed cuckoos breed from southern Canada south to the Greater Antilles and Mexico. While the cuckoo is still relatively common east of the crest of the Rocky Mountains, biologists estimate that more than 90 percent of the bird’s riparian (streamside) habitat in the West has been lost or degraded as a result of conversion to agriculture, dams and river flow management, bank protection, overgrazing, and competition from exotic plants such as tamarisk.

Today’s action stems from a February 1998 petition, submitted by the Center for Biological Diversity (formerly the Southwest Center for Biological Diversity) on behalf of 22 groups in Arizona, California, Nevada, New Mexico, Oregon and Utah to list the yellow-billed cuckoo as an endangered species. In February 2000, the Service determined that the petition presented substantial information and launched a comprehensive scientific review to determine whether the cuckoo required ESA protection in the West.

At the same time, the Service said it would fund a study of geographic variation to help address the question of whether the western yellow-billed cuckoo was a valid subspecies. The agency also agreed to assess whether it is separated by other physical, physiological, ecological or behavioral factors to the degree that it would merit listing as a distinct population segment (DPS) of a species.

Due to workload priorities, the Service was unable to act on the Center’s petition within the 12-month time frame prescribed by the ESA. Consequently, the Center filed suit in Federal court in Oregon, and in October 2000 Judge Garr M. King ordered the Service to complete the 12-month finding by July 19, 2001. During its review, the Service solicited scientific information and other comments from the public on the cuckoo and commissioned a genetics study, completed by Robert Fleischer, Ph.D, of the Smithsonian Institute. This information helped shape the Service’s determination on the songbird.

The Service has determined that the yellow-billed cuckoo in the western United States, roughly west of the crest of the Rocky Mountains, meets the criteria to qualify as a DPS, and, as such, may be proposed for listing. The DPS is based primarily on the marked separation from other populations of yellow-billed cuckoos. Birds within this DPS are located in the states of Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Texas, Utah, Washington and Wyoming. For Montana, Wyoming and northern and central Colorado, the boundary coincides with the Continental Divide. In southern Colorado and New Mexico, the boundary coincides with the eastern boundary of the upper Rio Grande drainage, including the Sangre de Cristo Mountains and excluding the drainage of the Pecos River. In west Texas, the DPS boundary is the line of mountain ranges forming a southeastern extension of the Rocky Mountains to the Big Bend area of west Texas, the western boundary of the Pecos River drainage.

The yellow-billed cuckoo is listed as endangered under the California State Endangered Species Act. In Arizona, where the largest cuckoo population west of the Rocky Mountains continues to be found, the Arizona Department of Game and Fish considers the bird to be a species of concern, which does not confer statutory protection for the species. The cuckoo is designated as threatened in Utah. These State listings do not confer the same regulatory protection as the Federal ESA.

The Service published the petition finding for the cuckoo in today’s Federal Register. As a result of this finding, the Service will add the western DPS of the yellow-billed cuckoo to the list of species that are candidates for listing under the ESA. Because the yellow-billed cuckoo is a species that was petitioned for listing, the ESA requires the Service to conduct an annual review of its "warranted but precluded" finding. The Service encourages State and Federal agencies as well as other parties to give consideration to these species in environmental planning.

For further information on the yellow-billed cuckoo, contact Jim Browning or Stephanie Brady at the U.S. Fish and Wildlife Service, Sacramento Fish and Wildlife Office, 2800 Cottage Way, W-2605, Sacramento CA 95825 (telephone: 916-414-6600).

The U.S. Fish and Wildlife Service is the principal Federal agency responsible for conserving, protecting and enhancing fish, wildlife and plants and their habitats for the continuing benefit of the American people. The Service manages the 94-million-acre National Wildlife Refuge System which encompasses more than 535 national wildlife refuges, thousands of small wetlands and other special management areas. It also operates 70 national fish hatcheries, 64 fishery resource offices and 78 ecological services field stations. The agency enforces Federal wildlife laws, administers the Endangered Species Act, manages migratory bird populations, restores nationally significant fisheries, conserves and restores wildlife habitat such as wetlands, and helps foreign governments with their conservation efforts. It also oversees the Federal Aid program that distributes hundreds of millions of dollars in excise taxes on fishing and hunting equipment to state fish and wildlife agencies.

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