Lately I’ve noticed flocks of these striking birds foraging on the desert floor, and singing in trees. White-crowned Sparrows hop around, kicking at the soil, uncovering seeds to eat. During breeding season in spring and summer, they establish and defend territories, hunting insects, caterpillars, wasps, and beetles, for themselves and for their young.
White-crowned Sparrows are famous for their dialects, common songs that vary slightly depending on where they live. Young males learn the local songs from other males in the neighborhood when they are just 2-3 months old. Females also sing, but their songs are more limited and related to defending breeding territories and feeding grounds.
A White-crowned Sparrow’s song is key to its survival, helping to attract mates and to defend nesting territories, with a particularly vigorous song warning off other males. Dialects of White-crowns are quite distinct – imagine a Southern drawl or a Yankee twang, and the boundaries between dialect areas are sharp. Sometimes a particular White-crowned sparrow dialect is only learned by males within a several mile area, and the sparrows just on the other side of this sparrow defined boundary sing a slightly different song. Birds that live in the middle usually learn both dialects.
These distinctive dialects make the sparrows prime candidates for many types of scientific studies. Using digital recordings of White-crowned Sparrows’ songs recorded over many years, scientists report that birds in urban areas are evolving to sing at higher frequencies so as to be heard over city noise.
This sparrow can be found across the North American continent, generally breeding in the far north and wintering in southern areas. Some stay in place all year, others undertake long migrations. White-crowned Sparrows that breed in Alaska migrate 2600 miles to winter in Southern California.
To hear the song of the White-crowned Sparrow click the link below.