Colimbo Común
A simple vista
Rango e identificación
Mapa de migración y distribución
Descripción
The naturalist John Muir, who knew the Common Loon during his early years in Wisconsin, described its call as "one of the wildest and most striking of all the wilderness sounds, a strange, sad, mournful, unearthly cry, half laughing, half wailing." Expert divers, loons have eyes that can focus both in air and under water and nearly solid bones that make them heavier than many other birds; they are able to concentrate oxygen in their leg muscles to sustain them during the strenuous paddling that can take them as far as 200 feet (60 meters) below the surface. Their principal food is fish, but they also eat shellfish, frogs, and aquatic insects. In recent decades, acid rain has sterilized many lakes where these birds formerly bred, and their numbers are declining. A leading cause of loon mortality is lead poisoning caused by the ingestion of lead fishing tackle.