When it’s cold, we bundle up in our hats, coats, and gloves. However, if exposed to extreme cold temperatures for too long, even with the help of proper winter gear, the bitter chill finds its way through our carefully layered clothing. It’s only natural to wonder how Alberta’s birds manage the winter chill, without the benefits of heated homes or clothes!
Feathers
Boreal Owl, credit to Gerald Romanchuk. This individual is fluffing their feathers to stay warm.
A birds first method of defense against the cold weather are its feathers. Not only do they provide insulation from the cold, they also have a waterproofing factor. Feathers trap pockets of air around the body, the birds internal body temperature will then warm up the trapped air. Birds will fluff their feathers in the cold so that they can trap as much air as possible, maximizing this insulating effect. To maintain the pockets of air, a birds feathers must be flexible, clean, and dry.
Birds produce a special oil called preen oil, which some cold-adapted birds use to waterproof their feathers. Anybody who takes part in outdoor winter activities knows that the key to staying warm is staying dry, and preen oil helps ensure no moisture gets in. It allows the bird to have a water resistant top layer and a heated inner layer - just like the ideal winter coat!
Changing Temperatures
Torpor is a state of reduced metabolism that is induced when a birds body temperature is lowered so that it will require fewer calories to maintain a appropriate heat levels. Many birds will enter torpor to save energy during chilly winter nights. Torpor is not very common in winter birds like the Black-capped Chickadee, because warming back up in the morning would take up too much extra energy. Instead, they experience a more moderate version of torpor called “regulated hypothermia”. Entering torpor can sometimes be dangerous, as the reduced temperature can lead to slower reaction times, which increases the bird’s vulnerability to predators.
How to Help
Although birds have many adaptations to conserve heat, bird mortality can be very high during harsh winters or in sudden cold snaps. To give your neighbourhood birds an advantage during Arctic-like conditions, make sure you keep your bird feeders stocked with foods that are high in fat and calories such as seeds, peanut butter, and nuts. These fill birds with plenty of energy that will enable them to generate more body heat. Birds can use energy to melt snow into water that they can drink but this will lower their body temperature. Providing water from a heated bird bath will give your neighbourhood birds a much better chance of survival.
Clark’s Nutcracker - Betty Fisher
Worrying about our nonhuman neighbours in the bitter cold is a kind gesture, especially when the cold arrives suddenly. Alberta’s feathered winter residents have plenty of adaptations to help them survive sub-zero temperatures, including caching food for use throughout the cold season. Not all birds cache their food, but all birds need natural habitat in order to survive the coldest temperatures of the year.
A great way to ensure that birds can withstand our increasingly varied weather is to protect their natural habitat, and supporting local nature conservation in your area goes a long way towards ensuring the long-term survival of all bird species. You can do this by supporting EALT - joining one of our black knot removal events to help keep fruit-bearing trees (and the birds that rely on them) healthy is a great way to do this!