There’s an outbreak of bird beak deformities in Alaska, British Columbia, and Washington, and scientists are trying to figure out what’s behind it. Birder’s World reports that black-capped chickadees, Northwestern crows, red-breasted nuthatches, and other birds are turning up with deformed beaks at unprecedented rates:
According to biologists with the U.S. Geological Survey’s Alaska Science Center, more than 6 percent of adult black-capped chickadees and almost 17 percent of adult Northwestern crows in Alaska are developing grossly overgrown and often crossed beaks every year. …
“Together, the prevalence of beak abnormalities in adult Northwestern crows and that in black-capped chickadees in Alaska represent the highest rate of gross deformities ever recorded in wild bird populations,” write Caroline Van Hemert and Colleen M. Handel in the October 2010 issue of The Auk, the quarterly journal of the American Ornithologists’ Union.
The scientists haven’t yet put their fingers on the cause of the deformities, which can arise from environmental contaminants, nutritional deficiencies, or infections. Their appearance “can be an early sign of a much larger underlying ecological problem,” Hemert and Handel wrote.
Dan Joling at Huffington Post spoke to the researchers and reports that previous outbreaks of beak deformities have been associated with environmental pollutants such as organochlorines in the Great Lakes region and selenium from agricultural runoff in California.
The affected birds, the scientists told him, live altered and sometimes shorter lives:
The deformities affect birds’ ability to feed, Van Hemert said, though many birds appear to cope by relying on food provided by humans at feeders rather than foraging.
Deformed beaks also can prevent adequate preening, she said, leaving feathers matted, dirty and without insulating value needed to survive the cold.
Read more about the deformities–and report them if you’re a birdwatcher who lives in the affected areas–at the website of the Alaska Science Center.
Image by Wayne Hall.