Most songbirds head south for the winter, as food supplies disappear, returning to breed in the spring, when booming insect populations can satisfy clamoring broods. Not crossbills.
PBS Nature, January 15, 2019
Most songbirds head south for the winter, as food supplies disappear, returning to breed in the spring, when booming insect populations can satisfy clamoring broods. Not crossbills.
PBS Nature, January 15, 2019