Monday, January 4, 2021

How Do Birds Survive The Winter? By Cornell Lab of Ornithology - Bernd Heinrich

                                                                              Illustration by Megan Bishop

<<It seems logical that most birds flee the northern regions to overwinter somewhere warmer, such as the tropics. Their feat of leaving their homes, navigating and negotiating often stupendous distances twice a year, indicates their great necessity of avoiding the alternative—of staying and enduring howling snowstorms and subzero temperatures.

However, some birds stay and face the dead of winter against seemingly insurmountable odds. That they can and do invites our awe and wonder, for it requires solving two problems simultaneously.

The first is maintaining an elevated body temperature—generally about 105°F for birds—in order to stay active. Humans in the north, with our 98.6°F body temperatures, face the same problem during winter of staying warm enough to be able to function, as anyone walking barefoot at –30°F will attest to within seconds.

The second problem to be surmounted in winter is finding food. For most birds, food supplies become greatly reduced in winter just when food is most required as fuel for keeping them warm.

One might wonder if birds are endowed with a magic winter survival trick. The short answer is: they aren’t. They solve the winter survival problem in many ways, often by doing many things at once. Although some species have devised the evolutionary equivalent of proprietary solutions, most birds follow a simple formula: maximize calories ingested while minimizing calories spent.>>

And, of course, they appreciate our bird feeders and a water source to help them during the cold Winter months.

Complete article with specific birds and more illustrations:  WinterBirds