This bald northern cardinal often visits my backyard. What causes such an unusual condition?
—Jane Fraise, North Attleboro, Massachusetts
George: This northern cardinal is probably suffering from a bad case of lice or mites that have destroyed the feathers on its head. All birds have parasites. To control them, they preen, or comb, their feathers often and sometimes take dust baths. Others expose their feathers to anthills, where it's believed the formic acid from crushed ants helps rid their bodies of parasites. Unfortunately, it's sometimes difficult for birds to clean their head feathers thoroughly. I, too, have seen northern cardinals with this condition. They're sure ugly without their red crowns. But the birds aren't sick, and most continue normal activities. In time, their feathers should grow back.