The wave of cold weather that struck the county earlier this week chilled most humans, but have you ever thought about the impact cold weather has on wildlife, especially small birds?
Many birds migrate to warmer climates during the winter but there are literally thousands of birds wintering in Lake County. How do these birds survive when the air temperature dips down into the low-20 degree range, or even colder?
For thousands of years, nature has prepared wildlife to cope with the changing environment. Some animals such as deer grow heavy coats while others dig a hole in the ground and go into hibernation during the winter. Yet others learn to survive by controlling their body temperature. For example, certain birds can cut off the blood supply to their legs and feet, which conserves heat for the rest of their body. They also fluff up their feathers to create air pockets. Different species of birds also grow extra feathers during the fall. Some even flock together at night to provide warmth. Another trick birds use to keep warm is to stand on one leg with the other leg tucked up tight to their body. After a while they switch legs, which keeps their blood warm. A bird’s normal body temperature is approximately 110 degrees. Many birds also shiver to keep their body temperature up. A few degrees of warmth can mean the difference between survival and death.
In the winter, food is critical for a bird’s survival. Most of the insects they feed on during the summer months are gone and they have to rely on seeds and other plants. The problem is that seeds and grasses don’t provide the same amount of protein as insects. An extra layer of fat on a bird is just like wearing a coat for us.
Thousands of birds survive the winter by visiting bird feeding stations put out by humans. The problem is that these birds become dependent on humans to feed them and if that food supply ever disappears the birds often starve. Most wildlife biologists don’t recommend feeding birds and say you should let nature take its course. That’s hard to do sometimes, especially if you enjoy watching the antics of the birds at your feeders.
Larger birds such as wild turkeys have to feed throughout the day to maintain their body heat. These birds feed mostly on acorns and other seeds. Meat-eating birds such as hawks, eagles and vultures are constantly on the lookout for a meal and they actually fare quite well during the winter months because a lot of birds and other wild animals succumb to the elements.
Ducks and other waterfowl stay warm even when swimming in ice cold water because their feathers have a wax-like coating and they also have a coat of heavy down beneath their feathers. This keeps the body of waterfowl dry and warm. Of course, they still have to eat to maintain their body fat. Actually, just about all waterfowl migrate from areas that freeze to a warmer climate. The Sacramento Valley is a good example. Thousands of ducks and geese migrate from as far away as the Arctic to spend the winter in the valley.
Small birds spend just about all their daylight hours feeding during the winter. They also spend most of the daylight hours huddled deep in trees. Not only does the tree provide shelter but it also holds a certain amount of food such as insects and seeds. The smaller birds also tend to flock together when feeding. They do this for protection against hawks and other predators.
All this raises an import question. Should we put out bird feeders during the winter months? Even scientists can’t agree on this. Some say feeding birds during the winter make them too dependent on people, which is bad for all wild creatures. Others say it doesn’t hurt or help the birds because in the end they will still find their food.
