Monday, February 3, 2014

Should we migrate this winter??

By Beth Sullivan
Isn't it just mind boggling to think that creatures as fragile and beautiful as birds, can survive such winter weather as we have been experiencing?
They not only survive, but many seem to relish the cold and snow. Nature has endowed them with numerous adaptations, physical and behavioral, that ensure that most will indeed make it through the winter.
You don’t have to go far to make observations. As lovely as a walk might be, out and about on a beautiful trail, you can learn plenty about birds from the comfort of your warm home.
Simply: if a bird can find food, it will remain here and survive the winter. With super high metabolisms, birds need constant fuel. They will search out the highest caloric foods. Nuts and seeds are high in fat and protein but often the effort to find and crack seeds seems to be greater than the value of the food. Watch a Chickadee fly back and forth to your feeder. Each time it grabs a seed, it must fly away to a hard surface, grab the seed between its feet and chip away at it until it opens. They seem to be in nonstop motion throughout the day.
Chickadee working to open a seed.
You may notice that there are still berries on a number of species of shrubs. The cold temperatures preserve them, even ferment them, making them quite warming to those birds who seek them out, like Robins, Bluebirds and Cedar Waxwings.
Most insect eaters will have flown south, but some Woodpeckers and Nuthatches know how to find insects, eggs and larvae hidden under bits of bark on tree trunks and branches.
Downy Woodpecker rests on the lee side of a branch.
Suet provides high fat, protein, seeds and even berries and will be visited by many birds in winter, even those usually not associated with suet feeding. With good food sources, birds will pack on the grams of extra fat to keep them warm and get them through the long nights.
Bluebirds enjoying a suet snack.

Grackle eating suet
Feathers: hard to believe those delicate feathers can provide enough protection to keep those little bodies warm. Birds actually will add a layer of down during the winter months. It doesn’t change their appearance. Watch a bird sitting on a branch and you might notice him fluff up a bit. By doing this, he can trap more warm air around himself. Think of us using several light layers instead of one heavy one, for most warmth.
White Throated Sparrow fluffs up to insulate himself.
Observe a bird on a tree trunk. In the wind and cold they will find the lee side or the sunny side to just rest and save energy. Birds do shiver. They contact their muscles, alternating groups, and create warmth from the action. That is really hard to see under all those feathers!
Brown Creeper looks for food under bark and lichen.
Cold Feet? Ever wonder how water birds, as ducks and geese and gulls can stand on ice and not suffer the consequences? The circulation in their feet and legs is quite unique, preventing truly cold blood from returning to the core, but warming it on the way! Watch as small birds in the snow or gulls and others on the ice, will stand on one leg and curl the other up into their breast feathers for warmth. That helps too.
Ring Billed Gull with one leg warming
So take a walk and search out the birds enjoying the winter. Or better still, find a window, get out your binoculars, learn your feeder birds and notice the small things that help them survive. It will help you with our challenge next week!

Photographed by Beth Sullivan. 

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