Food for Thought on Bird Feeders
In most contexts, it’s considered a bad practice, even a form of cruelty, to feed wild animals. If you’ve been to a national park, you’ve seen and heard the warnings. I recall a visit to Yosemite where messaging about not feeding bears was pervasive. The Park’s 300-500 black bears are naturally shy of humans, but when they learn to associate food with people, that behavior can change quickly. “Even a single, empty chapstick container or candy bar wrapper can result in a bear breaking into your car.” Yikes for the typical family minivan, amirite?
Fed animals (think bears, alligators, rats) pose a threat to humans. And human foods are a threat to wildlife. Most animals have specific nutritional needs that revolve around a variety of natural foods available in their environments throughout the seasons. They may happily accept easy-access human food, but that doesn’t mean they’ll get from it the balanced diets they need for survival.
How does this relate to back yard bird feeders?
The good news is, most feeders are filled with seeds that are nutritionally beneficial to their intended recipients. Also, wild birds don’t lose their instinctual fear of humans.
However, feeders can harbor bacteria like salmonella and E. coli. Cases of avian conjunctivitis, which can lead to blindness and death, have been traced to unclean bird feeders. Also, luring birds to the same place on a predictable schedule makes them more vulnerable to predators, such as cats and hawks.
Feeding can also change bird behavior. Research suggests cardinals and Carolina wrens have extended their range north partly as a result of feeders. Some normally migratory hawks opt to stay put because birds at feeders provide enough prey. In the larger scheme of things, these may or may not be negative developments for the cardinals, wrens and hawks, but we should look skeptically on any wild animal behaviors changed by human intervention. In addition, a few studies have linked bird feeding to lower egg production and hatching success, although it’s unclear why.
A recent study in the U.K. found that, as feeding has ramped up over the past 25 years, populations of adaptable and aggressive generalists, including native-to-the-U.K. great tits and Eurasian nuthatches, as well as invasive ring-necked parakeets, have skyrocketed, while woodland species that avoid feeders, such as wood warblers and marsh tits, have experienced steep declines. Apparently, the well-fed feeder-using species steal the nest holes and hatchlings of the feeder-averse species. In the words of one of the study’s authors, “If you’re dumping millions of tons of additional nonnatural resources into an environment, you’re going to get massive, massive impacts. And they’re not always going to be the ones you’re expecting.”
So attracting birds with feeders has pros and cons. Wanna know another way to feed birds that’s all upside? Planting native plants.
Native trees, shrubs, vines, perennials and annuals provide seeds, to be sure. But they also yield berries and insects (think caterpillars), which are critical diet mainstays for most birds, and nectar for pollinators such as hummingbirds. Critically, they also offer cover from predators and weather, places to nest, and even nesting materials.
Sam Droege, a wildlife biologist for the U.S. Geological Survey, remarks, “It is hard to ecologically justify removing native habitat to create a house and lawn, and then putting up feeders filled with bird seed.” Even more so when you consider that it takes hundreds of thousands more acres of plowed-under prairie and swampland to farm that bird seed.
So much better to fill our yards with seedy, fruit-bearing and insect-attracting native plants in the first place. I’m not saying you need to get rid of your bird feeder. But please also consider adding some biodiverse habitat to help meet the full range of those birds’ needs.
Speaking of essential foods, here’s the California Honeydrops on Carolina peaches:
Resources:
“Are You an Animal Lover?” National Park Service.
“Bear Information,” Yosemite National Park.
Asher Elbein, “Bird Feeders Are Good for Some Species – But Possibly Bad for Others,” Scientific American, March 4, 2022.
“Feeding Wildlife: You May Be Doing More Harm than Good!” Maryland Department of Natural Resources.
Caitlin May, “The Hidden Harm in Feeding Your Local Wildlife,” U.S. Fish and Wildlife Service.
Melissa Mayntz, “Bird Feeding: No Bird Feeders Required,” The National Wildlife Federation, November 28, 2016.
Matthew L. Miller, “Are Bird Feeders Helping Cardinals Expand Their Range?” Cool Green Science, The Nature Conservancy, March 20, 2018.
Susan Morse, “To Feed or Not to Feed Wild Birds,” U.S. Fish and Wildlife Service.
If you live in the DC vicinity and could use assistance with sustainable landscaping, visit Bees’ Knees Design. I’d be happy to help you.
clever possums
Thanks, Sarah. You raise a good point that I didn't really get into: bird feeders often end up supporting non-bird species whose populations are already disproportionate to their ecosystems.