Photo by Jim Conrad, Wikimedia Common
I feed birds all year around, although I cut back substantially in the summer time, only keeping a couple of feeders going to attract birds to the yeard so I can see them.
It is just as important to keep your feeders clean in the summer as in the winter. We have been having doves (especially white-winged doves shown in the photo) coming in to Wild Bird Rescue extremely emaciated. We have checked for trich, but there is no sign. The best guess from the symptons is aflatoxin from a fungus that grows in seed when it is hot and humid--the perfect description of our weather over the past month. Although the humidity is starting to drop, it is still unusually humid for our area over the summer.
Store your bird seed in a clean, dry place if possible. Clean and disinfect your feeders weekly. This will help prevent aflatoxins and other diseases that pass from bird to bird.
Also, many of you are trying to attract hummingbirds. The sugar water mixtures we feed are very prone to breeding harmful bacteria, especially in the heat. Replace your nectar every three days. preferably before it develops a cloudy appearance. Clean and disinfect at least once a week. If you feel you are throwing away a lot of sugar water, mix only half as much at a time.
We all enjoy watching the birds in our yard. In return we should do our best to keep them healthy.