Distribution and Migration of the Black Rosy Finch

Abstract

The Black Rosy Finch (Leucosticte tephrocotis atrata) was found to intergrade with the Gray-crowned Rosy Finch (L. t. tephrocotis) in the Bitterroot Mountains of the Montana-Idaho border, and the Seven Devils Mountains on the Idaho-Oregon border. It is believed that the dark wallowa population of L. tephrocotis is a result of similar intergradation and that atrata and australis should be considered as subspecies of L. tephrocotis. The breeding range of the Black Rosy Finch includes the high mountains of southwestern Montana, northwestern and north-central Wyoming, central Idaho, northeastern Utah and northeastern Nevada. In winter it is found primarily in Utah, Nevada, Colorado and the southern half of Wyoming. Black Rosy Finches migrate to lower elevations in winter and at least 300 miles southward. The movement to lower elevations may be stimulated by a lack of water in the alpine habitat. Lack of capped Rosy Finches (L. t. australis in Colorado and southeastern Wyoming. Aridity, small area of available habitat, or lack of precipitous cliffs for nesting seem to prevent the birds from populating the several isolated mountainous areas farther south and west of their breeding range