Keeping Clean: House Sparrows

It’s critically important for birds to take good care of their feathers.  They use their feathers not just to fly around to find food and avoid predators, but also to keep their body temperature at an appropriate level.  It may come as a surprise then that some birds spend time rolling around in dust or sand, but it actually improves feather quality.  After making a small depression, a bird presses its belly into the dust, fluffs up its feathers, and shakes itself back and forth to get the dust moving across all parts of its body.  The particles of dust help align the barbs of the bird’s feathers and reduces built up moisture, oil, and dandruff on its skin.  It also can shake loose parasites like lice, mites, and fleas.

I found this flock of House Sparrows in a patch of dust along the side of the road at the beginning of August.  It was an entertaining scene, with a chaotic mix of at least twenty sparrows flinging dust in all directions, plus juveniles fluttering their wings to beg adults for food.  The whole flock scattered each time a car drove by, but they were back at it less than a minute later.

In addition to dust bathing, birds care for their feathers by bathing in water, using bird baths, puddles, the shallow edges of lakes, or even the morning dew that forms on leaves and grass.  Many birds also use sun bathing, which encourages the parasites to move to shaded parts of the body where they are easier to remove.  Sun bathing is also important just because of the energy provided by the heat of the sun, warming the bird’s body while allowing it to conserve the energy it gains from its food.

Many songbirds use an additional method to care for their feathers, called “anting.”  The bird will allow ants to crawl over its body (or sometimes it will pick up the ants and place them on its body).  The ants attack many of the parasites found under the bird’s feathers.  Some birds will crush the ants and rub the dead ants on their feathers, using the formic acid produced by the ant as a deterrent to parasites.  When ants are not available, some birds have found other sources of acid to protect their feathers, including beetles, mealworms, and sumac berries.  In urban habitats, they’ve even been seen using coffee, chocolate, or even cigarette butts.