Claws for thought

Through our Big Garden Beak Watch survey we have been charting lots of birds with beak deformities in gardens. One of the proposed causes for beaks that become very overgrown is a condition called Avian Keratin Disorder, in which the production of keratin in the beak is greatly accelerated.

Keratin is an important material for birds, forming the basis of their beaks, feathers and claws. So, could Avian Keratin Disorder also lead to accelerated growth in these other body parts? The evidence is less clear but there have been suggestions that, in claws, it could. For instance, this Goldfinch might be affected by the condition. Elongated claws are reported less often than elongated beaks perhaps because they are more difficult for people to see and/or because long claws are more easily broken than long beaks.

Please let us know about any birds that you see with extra-long claws: gbw [at] bto.org



Goldfinch, spotted by Maria Cowans in Southampton.



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