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WatchList Species Account
for Brown-capped Rosy-Finch (Leucosticte australis)
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Photo: © Scott Streit
www.bird-friends.com |
Of the three closely related rosy-finches
in North America, the Brown-capped is the most southerly and
has the smallest breeding distribution, being almost endemic
to Colorado, with a scattering of sites in southern Wyoming
and northern New Mexico. Like the two other North American
rosy-finches, it breeds at the highest elevations of any species
north of Mexico. In summer, it feeds on windblown insects
and seeds frozen into snowfields.
Most nest sites are in cliffs or rock slides
near snowfields or glaciers. Some nests and young fall victim
to raiding Clarke’s Nutcrackers. In winter, it seems
to prefer to remain at the highest elevations where food is
still available and retreats to parklands and valleys at lower
elevations only in the presence of deep snow or severe storms
but moves up slopes to forage on alpine tundra areas where
the ground is blown free of snow. Winter flocks also visit
feeders and roost in old cliff swallow nests, caves, and farm
buildings.
There are no estimates available of population
trends, though Christmas Bird Count data suggests a drop in
numbers over the last 30 years. Its breeding areas are too
remote to be disturbed on a regular basis by human visitors,
and most sites are within national forests, national parks,
and wilderness areas. Upward movement of the tree line due
to global warming could eliminate some breeding sites. The
species is more vulnerable to human disturbance during the
winter, when flocks along highways are in peril from passing
cars.
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