Observation: This evening a black-capped chickadee (Poecile atricapillus) visited our feeder and we noticed the elongated bill. We have been watching the feeder carefully for visitors, as the mild winter seems to have reduced traffic or at least the amount of feed being used. I have not refilled a feeder all winter, which makes us think that maybe the song birds are able to get their elsewhere. Anyway, it has been over a year since we saw this phenomena the first time at our feeder. We will keep an eye out for more.
LEO says: (2014-03-18) Review the ANTHC-HUB LEO Network webinar presentation, Beak deformities in among wild birds in Alaska, by Caroline Van Hemert, Research Wildlife Biologist, U.S. Geological Survey, Alaska Science Center
Resources:
The Auk – The American Ornithologists Union, Epizootic of beak deformities among wild birds in Alaska: An Emerging Disease In North America? – 127(4):882-898, 2010 © (Handel C., et al. 2010)
Alaska Science Center – Beak Deformities, "Over the past decade, Alaskans have witnessed a startling increase of beak deformities among local birds. Large numbers of Black-capped Chickadees and smaller numbers of many other species of birds have appeared with grossly overgrown and crossed beaks." (U.S. Geological Survey)
Media:
Alaska Dispatch News (2016-04-05), video: Beak deformities in Alaska black-capped chickadees, by Tara Young, writes, "Beak deformities in black-capped chickadees have persisted in Southcentral Alaska for over 15 years, but researchers say they are making strides toward discovering the cause."
Juneau Empire (2016-10-25), Long, curved, akimbo: Hope uncovered for bird beak deformity, by Kan Joling, writes, "Biologist Colleen Handel saw her first black-capped chickadee with the heartrending disorder in 1998. The tiny birds showed up at birdfeeders in Alaska’s largest city with freakishly long beaks. Some beaks looked like sprung scissors, unable to come together at the tips. Others curved up or down like crossed sickles."
Alaska Dispatch News (2016-10-30), Newly discovered virus could be behind deformed bird beaks, by Yereth Rosen, writes, "Now scientists have unlocked one important clue that might explain the birds' woes — a previously unknown virus that appears to be closely correlated with the elongated and often twisted beaks."
Alaska Public Media (2016-12-06), Mysterious beak deformities may be caused by virus, by Shahla Farzan (KBBI), writes, "It’s been almost 20 years since large numbers of birds with unusually long beaks first appeared in Alaska. The birds, whose beaks grow at twice the normal rate, often die from starvation because they can’t feed themselves. Researchers now believe a virus may be causing the beak deformities."
