Nature: How Birds Survive Winter

How Birds Survive Winter

Winters are brutal enough for humans, so how is it that some birds manage to endure the harsh elements during Michigan winters, especially since so much of their food source, basically insects, and daylight are in short supply. Of the 650 species of North American breeding birds, more than half are migratory. This leaves a good many such as the northern cardinal, the Dark-eyed Junco and woodpecker braving the worst of the cold, wind and snow. To maintain body heat for survival there are a few strategies birds utilize. John Brenneman, Senior Avian Biologist with Kalamazoo Nature Center said “The most common way birds survive a cold winter night is by shivering to keep warm.” He added, “even the smallest species like the GoldenCrowned Kinglets, that stay in this area during winter, huddle in groups to keep warm. Bluebirds and woodpeckers stay in what’s called roost holes.” Communal roosting in a sheltered spot greatly improves a birds’ chances of surviving a winter when Michigan plummets into a deep freeze. An overlooked survival challenge is enduring twelve or more hours of darkness. Keeping warm during the day is hard enough, but it’s especially challenging at night. According to Audubon.org ‘when temperatures drop, birds must rely on every adaptation they have to survive their sleep. One of those adaptation’s is called torpor. Brenneman explains that torpor is, “like hibernating, but for only a short period. Where the animal will slow its heart rate and use less energy.” Overall, winter birds adapt by utilizing their fat reserves for fuel. Birds have been known to consume up to 35% of their body weight every day to survive bitter winters. Translation: For a 150-pound person, that’s the equivalent of eating 600 granola bars a day. One of the biggest questions that remains is what we as humans can do to increase a birds’ chance of surviving a harsh winter. A good start is helping to provide food and shelter. A backyard bird feeder is not only contributing to their well-being, but it can also be a visual treat to see the variety of species that come to feast.

You don’t have to spend a fortune on wild bird seed to fortify their winter diet. Birds actually can benefi t from a variety of nuts including peanuts, walnuts, Brazil nuts and almonds. Typically, they contain essential vitamins, fat and protein. Just remember bread is not a good nutritional choice to offer your backyard guests. Giving wild birds bread can be a contributing factor that leads to a condition called angel wing, which deforms the tip of the wings. Even helping our feathered friends with shelter can get a tad complicated. You might think they snuggle away in a nest during winter months, but nests are for egg incubation, leaving many birds fi nding winter rest or shelter in a protected perch or a tree cavity. Along with food, humans can contribute to shelter. A typical backyard birdhouse is not the best. A rooster house, however, is far more accommodating with thicker walls and a lower opening that conserves heat.

As we’re about to turn a corner toward winter, it’s blustery days will fi nd so many of us hibernating ourselves. We can fi nd some respite by gazing from our windows discovering brilliant hues from so many snowbirds gracing us with their presence. If you enjoy watching birds at your feeders, join the community science project Winter Feeder Count! Michigan resident can submit their information about the birds visiting their birdfeeders from November through April through a simple protocol. The information gathered is valuable for the protection of birds and the habitats they utilize. For details and to sign up, visitNatureCenter.org/WFC.

Kimberly Zewatsky Kalamazoo Nature Center