How Birds Adapt to Winter

 

The Tree Swallows Tachycineta bicolor shown above huddling on a branch during a snowstorm are demonstrating one way that birds stay warm during the winter. 

Of course, some birds move to warmer climates in winter, but many birds stay in New Jersey all year. How do birds can stay warm in the cold winter months? An article at fws.gov discusses ways that they cope. Here are some excerpts. 

Just like people, birds shiver to stay warm. Birds have much higher metabolic rates and burn more energy to stay warm than we do. Black-capped chickadees weigh less than half an ounce and can maintain a body temperature of 100 degrees Fahrenheit - even when the air is 0 degrees! They also have great insulation, stay active, and remember where they store their food. 

Like human homes, birds use insulation. Whether fat, fur or feathers, insulation matters for most cold-weather animals. And like many humans, cold-climate birds pack on body weight in the fall. People wear insulating clothing. Birds also trap pockets of air around their bodies, which requires having clean, dry and flexible feathers. 

People cuddle for warmth and so do small birds in shrubs, vines, evergreen trees, branches and wires.  Cavity nesters like nuthatches, titmice and downy woodpeckers use tree cavities and nest boxes to stay warm. Larger birds like American crows and ring-billed gulls are also known to flock together for warmth.

I hate having cold feet in winter. Birds hate it too and waterfowl species circulate blood through a countercurrent heat exchange, isolating the blood that flows in their legs rather than circulating it throughout their entire bodies. This helps to keep their body temperatures higher. Birds also have specialized scales on their feet and legs that help minimize heat loss. Many ducks, geese, pelicans, gulls and swans further conserve body heat by standing on one leg or even sitting down. Some birds will also tuck their bills under their back feathers to keep it warm and increase breathing efficiency by utilizing warmer air.

People can help too. Providing high-energy foods like suet, peanuts and black oil sunflower seeds and water year-round is critical. If that feeder you filled all summer goes empty in winter, birds who became used to feeding there are at a loss. A heated bird bath or one that you regularly de-ice and refill with clean water is also important to help keep birds hydrated. 

Photo By: Keith Williams, Creative Commons Attribution-NonCommercial-NoDerivatives 4.0