Subject: Re: Shorebird Behaviour - Thermoregulation? Date: May 2 14:07:33 1995 From: Jon Anderson - anderjda at dfw.wa.gov
It has been several years since I've taken my anatomy & physiology courses, but somewhere along the line I thought that I had been taught that the legs of birds in general were much less vascularized than, say, the legs of mammals. Less vascularization would tend to reduce heat loss, etc. I do know that small cuts to the birds' feet/legs that result from mist-netting tend to bleed less than similar cuts to my toes/fingers.
I can see that legs being wetted during feeding, etc would tend to radiate heat more than dry legs, and that only makes sense. However, waterfowl, grebes, loons, etc spend considerable time with their legs dangling in an excellent heat conductor - 36 to 50 degree (F) water. If the legs of birds were such good thermal conductors, I would imagine that water birds in general would be thermally stressed - and either they aren't or they've developed some other mechanisms to compensate for the heat loss. (As a person afflicted with male pattern baldness, I can sympathize with heat loss from a highly vascularized portion of my body to a cool/cold environment)
I would be interested in reading Piersma's paper, Stuart, if you could provide a reference.
Jon. Anderson Olympia, WA anderjda at dfw.wa.gov
On Tue, 2 May 1995, Stuart MacKay wrote:
> Theunis Piersma's work on Red Knot revealed that their legs make fantastic > radiators and help the bird considerably when dealing with tropical and > sub-tropical conditions. Looks like legs are pretty useful things ;-)