HOW DO BIRDS SURVIVE WINTER?
By Mark McKellar It is easy to understand why people rush out and by bird seed when it snows. How can something so small and fragile possibly survive such brutally cold conditions? Birds, like humans and other mammals, are homeothermic (warm blooded). This means that as long as birds can find a suitable food source, their bodies can convert that food into energy (i.e. body heat). Cold temperatures are survivable by most birds, it is the covering of the food source that is the main problem. Ground feeders and waterfowl know that their food sources are going to be covered up quickly, but arboreal (tree dwelling) species like evening grosbeaks and crossbills can ride out the same “cold” conditions that juncos and snow geese had to abandon. Given food availability, how do these tiny, fragile creatures endure sub-zero temperatures? Like us, they often try to find places that are well protected from wind and “cold air”. Evergreen trees provide very important cover as do artificial or natural
