Now that the leaves are off almost all the trees (oaks are holdouts), and the bird populations have shrunk, we are afforded an opportunity not easily available during the leafy spring and summer season; finding nests. Each summer, millions of birds build stick, mud, moss, grassy, leafy cups in trees, shrubs and bushes all around us. But out of necessity and through evolution they have learned to be very stealthy in the construction of these nests and in choosing the exact secluded location. There are exceptions of course; the house sparrows and robins will choose spots right on or next to our houses, but the vast majority of birds seek more solitude.
During these quieter winter months, when out bird watching you can make it a treasure hunt around your property or in the parks and state forests seeking these creations. Once found you can marvel at their construction and details. Besides all the natural materials, which can include feathers and horse or dog hair, you may find bits of string, plastic, or other inorganic materials. We had a great crested flycatcher use one of our nest boxes and after they fledged the young and abandoned the nest, I took it out to examine it. I had read that they often use shed snakeskin in the construction. I am still not exactly sure what it was that I found in this nest, but it appeared to be multiple small pieces of hard, white plastic and not a bit of snakeskin; a complete mystery. I hope they return next year and use the nest box again, because I’d like to see what turns up next time.
According to the Migratory Bird Act of 1918 (which is still in effect) it is illegal to possess bird nests, unless you have a permit to do so. It is however, OK to look at them and examine their contents and structure. Songbirds build these nests each spring and will not reuse them, so you are not harming the bird if you take one out of a tree or shrub to look at it more closely.
Sometimes it’s easiest to find old nests after the snow has fallen. Then all you have to do is search for something that looks like a frosted cupcake or maybe a snow cone. The snow mounds up on the cup like nest and sometimes white-footed mice will use that insulated space (yes, snow can act like insulation) to spend the winter.
While the birds that stay around for our winters cannot use the abandoned nests in any way during the cold months, they will seek shelter from the cold in previously occupied nest cavities. These are most often found in dead and hollow tree trunks, but sometimes they will use a bird house for shelter. Tree cavities are better insulated from the elements and a larger number of small birds, like chickadees can cluster together in them on bitter winter nights.
In addition to providing bird seed in the winter months, you can make sure there are nest boxes available. Place it in a south facing location, so passive solar energy will provide as much residual heat as possible. But be forewarned that when you open it in the spring you may find a mouse nest inside.
Two other ways to provide birds with shelter in the winter are brush piles; the thicker the better, and conifers with thick, closely spaced branches. Both provide shelter from the cold, but also from predators.
By Kate Crowley