Birds well-equipped for cold winter nights

We’ve been through some cold weather and some snow recently. A few visitors came from the South to watch the birds at the Fields Pond Audubon Center bird feeders.

They wondered, from the warmth of the building, how these chickadees, nuthatches and woodpeckers could get through such a cold winter. Also, they wondered, where did these birds go to get through the long, dark, cold night?

Well, first, birds wear vests of down under the smooth contour feathers of back, breast, belly and head.

Additionally, they eat a lot. Sunflower seeds have oil in them. Suet is high in calories, too. When the days are short, birds eat all day, and put on fat all day. They actually gain weight every day. They metabolize the fat at night to keep warm. By morning, they have lost weight.

First thing in the morning, they have to re-stoke the internal furnace. They might come to the feeder, but they might not. Trees are full of insect eggs and pupae.

Chickadees and nuthatches find the insect eggs and pupae among pine, fir and spruce needles, in cracks and crevices in the bark, on branches, on twigs and in the buds. Woodpeckers find them under the bark and in the wood. Insect eggs and pupae have glycerine compounds in them, which keep them from freezing – and also contain calories.

In winter, chickadees typically travel around in a group of six to 10 individuals, and generally spend the night perched on branches of a tree. Usually the perch is in a mid-height, evergreen tree. If the night is windy, an under-story conifer will give more shelter from wind and blowing snow than a tall tree gives.

When a bird perches on a small branch and crouches down, a tendon automatically pulls its toes tight around the branch, and the bird will stay firmly on the branch even when asleep. While sleeping, it will bury its bill and much of its head in the feathers just over the wing.

Nuthatches and woodpeckers will roost in a hole in a tree. Woodpeckers excavate a roosting hole in the fall and use it all winter. Nuthatches use pre-existing holes in trees, sometimes cavities made by woodpeckers. Sometimes a nuthatch can create a roosting cavity where a branch broke off a tree, and the wood inside has become soft enough to excavate.

For information on Fields Pond Audubon Center, call 989-2591.