"A beak deformity first recorded among blackcap chickadees near Anchorage is increasingly sighted in crows in Southeast Alaska, broadening an already mysterious phenomenon.
Blackcap chickadees, Northwestern crows and 25 other species of birds in Alaska have been reported with beaks up to three times as long as the normal size. The deformity often strikes mature birds and reduces their ability to feed and preen effectively. In many birds, the deformity leads to death.
"We don't know what's causing the problem," said Colleen Handel, a wildlife biologist with the U.S. Geological Survey's Alaska Science Center in Anchorage. She's been studying the beak deformities for five years. Though the phenomenon was first noticed in blackcap chickadees in the early 1990s, a deformed raven, a deformed Steller's jay and several deformed crows have been reported in Southeast Alaska since 1997. Southeast sightings have increased this year, biologists say.
The center has received 1,600 reports of deformed beaks in Alaska, compared with only 12 reports of beak deformities in the rest of North America combined. Those deformities could have been caused by genetic mutations. But the beak deformity in Alaska's birds is most likely caused by something other than DNA, Handel said."
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