Why don't ducks and other birds get frostbitten feet in the winter?
Rick Thompson inquired as to why ducks and other birds donít get frostbitten feet in the winter. Off to the Encyclodpaedia Brittanica Online went mrlucky, where the following text was gleaned.
(In birds) "Insulation is provided by feathers, together with layers of subcutaneous fat in some water birds. In cold temperatures, heat loss from the exposed, unfeathered feet is minimized by a reduction of blood flow to that part of the bird and by a network of heat exchange in the blood vessels of the upper leg."
In other words, a birdís pedal blood flow acts to maintain a circulation level low enough to conserve heat, and high enough to prevent tissue damage and frostbite.