sparrow migration -- 004

sparrow migration -- 004

sparrow range map

White-throated Sparrows are abundant, but declined over most of their range by about 35% between 1966 and 2014, according to the North American Breeding Bird Survey. The birds enter a migratory state based on their internal clock, which is normally synchronized to the changes in day length.

IMAGE: courtesy: U.S. Fish and Wildlife Service