Cuckoo for cuckoo birds? 10 pairs seen in these parts
A migrant bird that winters in South America and summers in the American West is bound for extinction, according to a federal agency, which is seeking comments on a proposed endangered listing for the bird.
The Western yellow-billed cuckoo, of which there are about 450 mating pairs in the United States, is threatened by dams, river-flow management and the loss of large cottonwood stands that offer a more humid environment conducive to the insects that form a major part of the bird’s diet.
About 10 mating pairs of the birds have been seen on the Western Slope.
The yellow-billed cuckoo is common east of the Continental Divide, according to the U.S. Fish and Wildlife Service, which noted that 90 percent of the Western yellow-billed cuckoo’s habitat has been lost or damaged.
The western population always was fairly limited to riverbottom cottonwood forests, said John Toolen, a wildlife biologist with the Fish and Wildlife Service in Grand Junction. Its ideal nesting habitat is fairly dense cottonwood stands with dense understory of willow and other native shrubs.
Much of the bird’s decline can be traced to the disappearance and aging of extensive cottonwood stands, many covering 200 acres or more, Toolen said.
Birds of late have been found in stands covering some 25 to 30 acres, Toolen said.
A critical-habitat rule for the Western yellow-billed cuckoo is set to be released later this month.
“We need to know a lot more about the plans” to save the cuckoo, said Bonnie Petersen, executive director of Club 20, the Western Slope lobbying and promotional organization, noting that the area that stands to be affected by an endangerment finding appears to be similar to that of the southwest willow flycatcher.
Some water projects in southwest Colorado have been halted by the flycatcher’s designation, Petersen said.
The Western yellow-billed cuckoo tends to live mostly in riverbottoms, which many times are on private land, Toolen said.
Developments on federal land would have to take the bird into account under the National Environment Policy Act.
As a migratory bird, the Western yellow-billed cuckoo has been covered since 1918 under international agreements, Toolen noted.
In addition to the aging cottonwood stands, farming and ranching, dams, stream-bank protection, overgrazing and invasive exotic plants are of particular concern to the bird.
The reclusive birds feed on caterpillars, katydids, grasshoppers, tree frogs, beetles and cicadas, all of which are affected by river-management practices, land disturbance and wildfire.
The birds already are extinct in the states of Washington and Oregon, and biologists say fewer than 1,000 mating pairs remain.
The Fish and Wildlife Service will accept comments through April 25 on the proposed endangerment listing. Comments may be submitted at http://www.regulations.gov, docket number FWS–R8–ES–2013-0104, or by mail to Public Comments Processing, Attn: FWS–R8–ES–2013-0104, Division of Policy and Directives Management, U.S. Fish and Wildlife Service, 4401 N. Fairfax Drive, MS 2042-PDM, Arlington, VA 22203.