Experts Explain How To Clean Bird Feeders The Right Way And Keep Them Safe During Nesting Season

Spring wouldn’t be regarded as spring unless you spot a lush flock of greenfinches trilling and twittering in your yard. When March arrives, these olive-green-hued finches jump out of their cup-shaped nests and start cracking nuts and seeds with their conical bills, per the Woodland Trust. As they feast on seeds, they inevitably leave droppings of leftover portions and cracked husks in and around the feeder. These leftovers decay and rot, which turns the feeder into a breeding ground of parasitic bacteria. This is why the population of greenfinches has declined by 70% since 1967. So, experts at The Royal Society for the Protection of Birds (RSPB) recommend that birdkeepers make it a habit to clean their bird feeders regularly.

Not just sunflower seeds, but any kind of seed or bird food, such as peanuts, suet cakes, sweet flower nectar, or anything else, strewn sloppily around a feeder can turn the feeder into a hotbed of disease. Plus, leftovers tend to invite visitors like squirrels, cats, dogs, and bad bugs to the feeder. Finches, especially greenfinches and chaffinches, are extremely vulnerable to getting infected by the bacteria that affect the feeder.

RSPB describes that the population of greenfinches has been on a steep decline over the past few years due to a common parasitic disease called “trichomonosis.” Caused mostly due to poorly-sanitized feeders, trichomonosis is a nasty parasite that infects the tissues in a bird’s mouth, throat, and esophagus, creating ulcers that make it difficult for the bird to eat and breathe. The parasite spreads into the bird’s body through saliva-contaminated food and water, per Forbes. Not just greenfinches, but just about any bird can be affected by the outspread of disease triggered by a grubby bird feeder.

“Bird feeders are a high point of contact, so disease can be transferred easily from one bird to another. If you keep your feeder clean, it can help reduce the chance of spreading disease further,” Holly Grant, a project assistant for NestWatch, said in Wirecutter to the New York Times. RSPB elaborates on a simple method to scrub away the filthy particles from the feeder. Step one is to put on a pair of gloves and discard the leftover food into a bin. Follow the drill by detaching the parts of the feeder, splashing it with hot soapy water, rinsing it with cold water, and giving it a thorough dry using a towel. Wrap up the cleaning by protecting the feeder with a disinfectant spray.

Doctor Emma Greig, project leader of the Project FeederWatch program, also suggests using a mixture of soap, hot water, and mild detergent to swab the feeder. For all those slinky crevices and tough-to-reach spots, birders can also add a scrub brush, toothbrush, bleach, or vinegar solution. Another tip the doctor shared was to use small feeders that empty more quickly. “It forces you to clean them more often and refill them more often,” she said in Wirecutter. Coupled with these techniques, the doctor encouraged birdkeepers to follow some simple tips to ensure that their feeders remained free of dirt and disease. 

For instance, washing your hands. Although trichomonosis is not transferable to humans, many diseases like salmonellosis can be passed to humans. Another tip is to ensure that the feeder is air-dried on a towel before refilling it with food. Leftover moisture can trigger the eruption of harmful bacteria, mold, and pathogens. Another benefit of cleaning your feeders regularly is that you’ll shoo away predators like squirrels. “Squirrels have just turned up for their tea. They're very confused and bang out of luck as I'm cleaning my feeders,” a birder named Steve Randall (@TheSteveRandall) wrote in a tweet.