With overnight temperatures dipping into the teen this week, I am sure you share my heightened concern for our backyard bird neighbors.  This anxiety stems from knowing that birds can freeze to death if they do not have enough energy and a “warm” place to roost at night.

       Some birds such as bluebirds, chickadees, and woodpeckers fend off the cold by roosting in cavities.  As you might expect, downy woodpeckers roost in natural cavities and on some occasions even in nest boxes.  What you probably did not realize is that downy woodpeckers chisel out winter roosting cavities.  Let me explain.  During the autumn and winter, downy woodpeckers chisel out their winter roost cavities. While they appear just like any cavity they excavate throughout other times of the year, winter roosting cavities invariably face away from the prevailing winter winds.  Cavities pecked out at other times of the year are randomly oriented. Consequently the interiors of cavities facing away from strong, icy winter winds are often much warmer than those facing in other directions.  As such, downy woodpeckers do not have to expend as much energy to keep from freezing.

       That is truly amazing!