Thursday, April 10, 2008

Survival of the not so fit?

It never ceases to amaze me of the consequences of us all now feeding our birds all year round. Birds that would have died long ago - because of some peculiarity - now turn up almost annually because their survival has been aided by easily obtained supplementary food.
The next individual in this saga is a Great Spotted Woodpecker, from Rosedale in north Yorkshire. This bird, observed this winter, has a bill that is about 150% bigger than is normal, but given easy feeding it has been able to survive (the fact that it normally has a large tongue will also help, but whether this too is increased in size?).
It would be interesting to know whether this bird has been witnessed boring /drumming, or creating nest holes, as I would think it would have insufficient leverage to make any sort of impression i.e. to be able to hold on and then swing its head back with sufficient movement to be able to create some 'force' at the bill-tip.
A normal bird is shown on the left, with our big-billed specimen on the right.
(Original article appeared in Telegraph on line).


Post a Comment

<< Home