As for land birds, if the rain is not too heavy nor too cold, most birds will keep feeding. ... As it turns out, only birds that nest in cavities are likely to have that luxury. Flocks of Pygmy Nuthatches pack into chiseled holes in dead snags like clown cars, where they seem to embody the meaning of “cozy”. read more
Birds found on land are more weatherproof when it comes to light rains, but when rains get stronger, the natural reaction, like people, is to seek out shelter. For example, songbirds would tend to cower and reserve their energy for a brighter day. read more
When rain arrives, most birds wait out the elements and rely on their water-repellent coats to help them do so. Birds, along with other warm-blooded animals, need to keep their body temperatures within a certain range to avoid becoming hypothermic. Birds have special fur or feathers that help to repel water, which keeps birds warm and dry. read more
Most birds have a home feeding territory. When it rains, they behave kind of like we do, hunkering down more, and sticking closer to the trees. Wet feathers are fine for preening, but make it difficult to fly. If your feeders are under a shelter, the birds may be more inclined to hang out there. read more
In that location is an oil gland. The bird grabs a tiny drop of the oil and uses it to condition it's feathers, thus adding a little weather protection and sunscreen as well. By preening, the birds reduce the water logging effects of rains, although many birds do get wet enough to make flight difficult, if they sit out in a downpour. read more