Anting

Anting is a behavior in which birds rub insects (usually ants) on their feathers. This releases liquids with chemicals such as formic acid onto the bird's feathers. Instead of ants, birds can also use millipedes. Over 200 species of bird have been known to ant.
We do not know why birds ant. Birds may ant because the chemicals released by the insects kill parasites on their feathers. Another reason is that it releases the chemicals the ants make onto the bird's feathers. The bird can then eat the ant without being hurt by the chemicals.
There are two forms of anting: active anting and passive acting. Active anting is when a bird picks up ants in its bill and wipes them on its feathers. Passive anting is when the bird lies down in a group of ants and opens up its wings so that the ants will crawl up into its feathers.