COLUMBIA — When temperatures sink and a 17-inch layer of snow blankets the ground, birds have trouble finding the food they need to survive.
MU biological sciences professor and bird specialist John Faaborg said ground-foraging birds struggle to find seeds in this weather. Common ground foragers in Missouri include white-throated sparrows, northern cardinals, fox sparrows and dark-eyed juncos.
He said the birds die during the winter, but their deaths are difficult to track because some birds leave the area if they cannot find food, and dead birds curled up in bushes or trees are difficult to find.
“There’s 17 inches of snow on the ground,” Faaborg said. “They can’t scratch away at that. With this kind of snow, they’re obviously hurting.”
Ground foragers fly south if they can’t find seeds, so after this week’s snowstorm, many have probably left, Faaborg said. But because the last snowstorm was so widespread, the birds might not have any luck farther south.
“Trying to move a few hundred miles south probably won’t help you, and it might be difficult to get the kind of fat to do that,” Faaborg said.
Faaborg said birds add 10 percent to 15 percent of their body weight during the day to get them through the cold night.
Award Pet Supply co-owner Chuck Everitt estimated his store sees a 30 percent to 40 percent increase in birdseed sales during the winter. He said customers also buy birdseed in larger quantities, such as five bags or more at once.
“People like to see birds in the wintertime, and they feel (a need to take care of) them,” Everitt said. “There’s not as much food on the ground for them to eat, so they put out the birdseed for them.”
Everitt said different types and sizes of seed draw different kinds of birds. For example, millet seeds attract cardinals, finches, sparrows and juncos.
“We have a chart that we can show them (that shows) what seed is best for what they’re trying to attract,” Everitt said.
Songbird Station manager Holly Seaver said suet, or rendered fat, is one of the best foods to give birds during the winter.
“It’s probably the most concentrated source of energy for them,” Seaver said. “It’s important to know that birds can usually consume a quarter to a third of their body weight a day, so they need that high-calorie food source.”
Seaver said winter is the busiest time of the year for birdseed, heated birdbaths, birdbath heaters and suet sales at Songbird Station.
Seaver has noticed more birds are coming to her bird feeder at home, which she normally fills every three to four days in the winter. The last snowstorm has increased demand.
“During this storm, I was filling twice a day,” Seaver said. “The colder it is, the more food they need to keep them warm.”