Ice presents stressful winter conditions, not only for people, but for wildlife. Though beautiful to witness from warmth and safety, a wintery mix of precipitation that coats food sources presents challenges for bird survival.

In Tennessee we have birds that live here year-around and remain for the winter because of the generally moderate winter conditions and abundance of food. If enough food is available, many bird species can survive temporary plummets in temperature. Extended periods of sub-freezing temperatures, however, such as the single digits that we recently experienced, and a quarter inch coating of ice over everything increases survival challenges considerably.
The American Robin is one of the species that we call resident birds because they remain during the winter. Many northern robins join our local ones to take advantage of the food sources, so we may see large flocks of robins descending on our yards and visiting fruit producing trees and shrubs. Asian holly is one of the berry producing shrubs that attracts many species of birds, though if you are planting holly, the native American Holly is a better choice. In these images, you see a Robin picking berries from the holly. He not only was feeding on berries, he soon claimed the holly for himself, driving away other robins and also driving away the area bluebirds that came to visit. He ignored sparrows, the Hermit Thrush and did not bother the Mockingbird, the bird we all expect to be territorial with a holly.
The ice and the several days of below 20 F temperatures, presented conditions so stressful, that many birds we normally don't expect to be aggressive were chasing others away from their food source. Above, you see the robin in the act of grabbing another berry. Notice what happens to the berry in the next image.
An ice coated berry is hard to hold on to! People feeding birds during the ice storm and deep freeze temperatures in east Tennessee noticed many territorial birds and an influx of species that weren't commonly seen visiting their winter feeders.
I'll show you some of those species in the next few posts.
Next: Bluebirds and ice--a special matter
More on wintering birds in this blog
A good article on Winter time feeding and water--Cornell






































