Do birdfeeders prevent birds from migrating in the winter?

From the Editors of E/The Environmental Magazine

Do birdfeeders prevent birds from migrating in the winter?

—Melissa Hildebrant, New Haven, CT

Despite common beliefs, there is no evidence that feeding wild birds changes their migratory patterns or makes them in any way more dependent on people, according to John Bianchi, a spokesperson for the National Audubon Society.” A bird’s migratory urge is primarily triggered by day length, and even a hearty appetite won’t make a bird resist that urge.

+3/44*g??nter at the Cornell University Lab of Ornithology concurs. “For most species, migration patterns are hard wired.” he says. Food resources do not seem to be a factor in migration habits. “Most warblers leave right after their breeding season, in August, when there are still abundant food resources, but the days are getting shorter,” he says. Studies show that even in four feet of snow, birds will get only a small portion of their food from your feeder anyway, and forage for the rest.

While bird feeders won’t make a huge difference in migration patterns, they can’t hurt. Yard bird feeders, particularly in winter, help both native and migrating birds whose feeding opportunities are compromised by snow, as well as development, pollution, pesticides, and the widespread planting of non-native vegetation, says Bianchi. Migration is responsible for the bulk of adult bird mortality, according to Bonter. Flying hundreds of miles requires significant energy and birds need to bulk up before they go, or they may not make it. The National Bird-Feeding Society has deemed February National Bird Feeding Month, in recognition of the hard times winter holds for birds. As the Society points out, birds can use up 20 percent of their body weight just to stay warm overnight and spend most of their waking hours looking for food. Plus, “people who feed birds often become good stewards of the land,” says Allison Wells, communication and outreach director at Cornell Lab of Ornithology.

CONTACT: National Audubon Society, 700 Broadway, New York, NY 10003, (212) 979-3000,,; Cornell University Lab of Ornithology, 159 Sapsucker Woods Road, Ithaca, NY 14850, (800) 843-2473,,; National Bird-Feeding Society, PO Box 23 Northbrook, IL 60065, (941) 962-4584,