Summer bird feeding requires so much conscientious attention that many people close their feeders for the duration. That’s not necessary if we ensure that we’re helping, not hurting, birds.
March and April are dangerous for winter finches, who often eat on the ground. Seeds and seed shells pile up under feeders, fostering bacteria and mold growth. Periodic thawing as spring progresses hastens the process, and so every year, disease outbreaks kill ground-feeding backyard birds. Rake up spoiled seed whenever weather and ground conditions allow, and screen compost bins to exclude birds. Seed catchers help if emptied before seed in them gets too wet, too. Seeds sprouting on the ground, in seed catchers, and in feeders indicate that a cleanup is in order.
Sunflower hearts eliminate the mess of seed shells but spoil faster, and wet cracked corn is also dangerous. Limit the amount you offer in summer to what birds eat in a day or two.
Any time of year, bird feeding can subsidize rodents. Effective squirrel guards keep rats out of feeders, but spilled seed is a rat magnet. Seed catchers beneath feeders help but, again, empty them every few days.
Songbirds focus on insects much more than seeds during nesting season. For a few years, it was in vogue to offer nesting birds, especially bluebirds, as many live mealworms as they could devour, but mealworms are calcium deficient. Providing a few mealworms once or twice a day can be helpful, especially during cold, wet weather, but when nestlings are fed too many, it inhibits proper bone development.
Carbs in grape jelly help fuel migratory flights and give catbirds and orioles extra energy when they’re nesting, but take in the feeders if they bring their fledglings more than once or twice a day. Growing birds need protein, not so many carbs.
Don’t make summer hummingbird mixture stronger than a quarter cup of sugar per cup of water. Sugar water ferments, so change it every two or three days and daily during hot spells.
Birds drink as well as bathe in birdbaths, and mosquito eggs hatch and mature quickly in warm weather, so clean birdbaths every day or two. Hosing yours down while swiping with a scouring brush minimizes algal growth.
Many people provide nesting materials in summer. Fibers should be shorter than about 8 inches long to prevent entanglement and dully colored for camouflage. Never use dryer lint: It feels great straight from the lint filter, but after getting wet, it shrinks, hardens, and crumbles.
Dog or cat fur pulled from a grooming brush from pets that haven’t been treated with flea and tick medication is an ideal nesting material. But what if you use flea and tick preventatives, either orally or in drop form? I’m not aware of any studies of nests with fur from pets treated with these medications. It’s possible the chemicals in the fur could help control lice and mites in the nest but equally possible they could harm incubating birds or tiny nestlings. Until scientists study the question, I think it’s better safe than sorry.