A dirty bird - what does it mean when they roll in the soil?

Q Outside a window of our Bloomington condominium is a patch of bare ground near several evergreen trees. My husband and I have watched with amusement and perplexity as wild turkeys, crows and squirrels have visited the same site to scratch the dirt and either throw the loose soil onto their wings or roll in it. What purpose does this behavior serve?

A It sounds like the birds are dust bathing, a practice that helps control parasites such as lice and mites.

Some birds also "ant," meaning they'll sit on an anthill and let live ants crawl through their feathers or, sometimes, they will use an ant, held in the bill, to jab or wipe their bodies, particularly under the wings and tail. Anting behavior usually involves ants that produce formic acid, but sometimes birds use other pungent materials, such as orange peels, raw onions, wasps, mothballs and burning cigarette butts. Control of external parasites seems a likely explanation of anting, but it might be that it just feels good.

In addition, some birds sunbathe. They sit on the ground and spread their wings while appearing to gaze directly into the sun. They are exposing to the sun as much of their feathers and the bare skin between their feather tracts as possible. Many kinds of birds exhibit this behavior, usually in response to direct sunlight and often on hot days.

The reasons are not clear. It might be that the birds are soaking up vitamin D produced by sunlight. If the bird becomes too hot, or hyperthermic, it will cool down by opening its beak and panting.

Source: Bell Museum of Natural History, University of Minnesota.