Evans, Tom, St Louis Post-Dispatch (MO)
IT'S NO FUN in the winter when the temperature stays around freezing for days on end. Humans may turn to hot chocolate, extra blankets and space heaters. But birds may need to turn to humans.
"Surviving the night can be a huge challenge for birds in winter," says Bill Bahorich, co-owner of Wild Bird Center, a retail store at 12388 Olive Boulevard in Creve Coeur.
The birds that spend winter in the St. Louis area mainly are seed-eaters, Bahorich says. They include cardinals, blue jays, chickadees, titmice, sparrows, mourning doves and juncos. The birds whose diets rely heavily on insects have migrated to warmer climates for the winter. They include barn swallows, purple martins and chimney swifts. Birds can find plenty of food and water when the temperature gets well into the 30s and beyond. But when a glazing of ice or layer of snow coats yards and fields, birds need help to find food. Also, the shorter days in wintertime decrease the number of hours that birds can spend foraging for food. And not only is food harder to find when the temperature drops, but birds need more of it because they need to generate more heatand energy to survive. "They will spend a lot of energy trying to keep warm, and they need to replace what they spend," says Carol Kershner, director at Wild Bird Rehabilitation, a nonprofit agency at 10040 Big Bend Road in Crestwood. "They need more energy to keep warm and keep their metabolism going." Those factors have led the National Bird-Feeding Society to declare February National Wild Bird Feeding Month. According to the society, 63 million Americans have bird feeders in their yards. "It's more important to continue feeding birds in the winter,"Kershner says. "There's less natural food around in the winter in suburban areas." Studies have shown that while birds usually get less than a fourth of their food from backyard feeders, in severe weather nearly twice as many birds with access to feeders will survive as opposed to birds without access to feeders. To keep warm through the night, birds add feathers and fluffthemselves up. If they can get enough food, they also can develop a fatty layer that provides insulation and helps keep them warm. In addition, birds lower their body temperature at night,Kershner says. "They exert less energy when maintaining a lower body temperature, she says. "Some species can lower their body temperature by as much as 10 degrees." Bahorich recommends stocking feeders with seeds that have a high oil content. "Birds need a high-fat, high-cholesterol diet. They need every edge they can get against the cold," he says. The most popular feed is black oil sunflower seeds, Bahorich says. …
What Birds Need Now . . . Easy Pickings
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février 06, 2019
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