In Alaska during the mid-1990s, bird experts noticed an uptick in overgrown, warped beaks among black-capped chickadees. Now, using high-throughput RNA sequencing, researchers at the University of California, San Francisco, and their colleagues have identified a candidate culprit: a new picornavirus, the authors reported last month (July 26) in mBio.
Avian keratin disorder can cause the top and bottom of misshapen beaks to swoop in opposite directions. The deformity, which affects the fibrous protein layer above the bone, impedes normal feeding and grooming. For the fist-sized chickadees that endure Alaskan winters, these can be fatal liabilities, National Geographic reported.
“It’s a gut-wrenching experience when we see these small birds with gross beak deformities,” study coauthor Colleen Handel, a wildlife biologist with the US Geological Survey ...
