Cold-weather skills of feathered friends
As many of you already know, it has been especially cold here in Georgia, with temperatures dropping below freezing more often than not. These cold days mean that many of our animals, who are not acclimated to or tolerant of this weather, remain indoors to keep warm. However, of the animals able to comfortably remain outside during these frigid days, you may notice most are of the avian variety. That’s right: Birds are some of the best cold-weather survivors out there!
In order to comfortably survive these freezing temperatures, birds have a few tricks up their sleeves, or should I say wings. A bird’s best cold weather defense is its outer layer of feathers. Feathers are exceptionally good at trapping in heat against a bird’s body while also keeping out the cold. When cold, a bird will fluff up its feathers, creating many small pockets of air that have been warmed by the bird’s own body heat. These spaces of warm trapped air create a barrier between the outside cold and the bird’s body like a jacket. Bird feathers are also coated in waterproof oil (produced by the bird itself) that help keep out the damp of melted snow or icy rain and add another layer of protection against the winter elements.
What about the parts that aren’t covered in feathers, you ask? Birds have a way of keeping these “naked” parts warm as well. One tactic birds use to keep their feet warm is by tucking a foot up into that “puffy jacket” of feathers we mentioned earlier to warm up, and then alternate with the foot left outside in the cold. Sometimes birds will even sit low to the ground or perch in order to shield both feet at the same time. Now, waterfowl, such as geese and ducks, have an even more complex method of keeping their legs and feet warm in the frigid winter water. This method, called a counter-current exchange, is when warm blood being pumped to the feet passes closely by the cold blood returning to the body, allowing for heat exchange between the two blood flows. This warmth exchange keeps the overall temperature of the feet low enough to significantly reduce heat loss to the outside and warm enough to avoid damage from the cold such as frostbite.
Even though birds of all shapes and sizes are armed with these tools to survive the cold, they could still use a helping hand on those particularly frozen days. When water sources such as puddles and lakes freeze, birds can have a hard time finding enough to drink with all the ice. Placing a dish of water out back, and even a few handfuls of bird seed, can really help the native bird life feel just a little cozier during this freezing winter.
Katherine Biddle
Keeper I, Birds
Connect With Your Wild Side #onlyzooatl