The winter solstice occurred Dec. 21 and, with it, the longest and most challenging night for our birds. Even in areas lacking bitter temperatures, the most overlooked winter survival challenge for birds is having to endure the long period of darkness during the night.
While roosting, a small songbird needs to sustain itself for 13 to 15 hours, solely by using its fat reserves for fuel. Keeping warm is costly. A bird expends about 60% of its energy generating body heat. To stay warm, songbirds may use up 75% to 80% of their fat reserves during a single winter’s night. That is equivalent to shedding and then replacing 10% of their weight in the form of body fat every 24 hours. For these birds, the daily challenge is to find enough food to not only make it through each day, but to also replace their fat reserves for the coming night — all in the course of limited daylight hours. A high fat diet is not good for us humans, but it’s absolutely essential for birds.
Birds at our backyard feeding stations eat ravenously first thing in the morning and just before dusk. A diet high in fat is an absolute necessity for them to survive the long, cold winter nights. Karen was up at dawn to replenish the feeding stations with black oil sunflower, suet and bark butter. The first bird she spotted in the trees was one of her favorites, a mountain chickadee. As she backed away from the feeders, the chickadee grabbed a sunflower seed, held it between its feet, hammered it apart with its beak and then flew away to stash it.
Mountain chickadees have a white eyebrow and pale gray sides that distinguish them from other chickadee species, such as the black-capped chickadee. Their call is a hoarse chick-adee-adee-adee.
For winter survival, the mountain chickadee has several things going for it. They are very active foragers. They have a half inch of insulating feathers with a unique structure that traps air close to its body, maintaining body temperature at 100 degrees Fahrenheit even when the air is at zero degrees. During the night, they lower their body temperature to save energy. Their feet are regulated near the freezing point and stay cold most of the time all winter long, even as their body temperature stays higher. They have a great memory of where they stashed food.
If you are patient, it’s possible chickadees will become tame enough to feed out of your hand. These gregarious birds are entertaining and a great addition to any backyard. Enjoy!
Ken Bunkowski and his son, Matt, are co-owners of Wild Birds Unlimited in Santa Fe and look forward to sharing the joy that birds bring into our lives.
