The Olive-sided Flycatchers, Contopus cooperi, is a passerine bird.
It is a medium-sized tyrant flycatcher.
Adults are dark olive on the face, upperparts, and flanks. They have light underparts, a large dark bill, and a short tail.
Distribution / Habitat:
Olive-sided Flycatchers breeding habitat is coniferous woods across Canada, Alaska the northeastern and western United States, and other types of wooded areas in California.
These birds migrate to Central America and the Andes region of South America.
Breeding / Nesting:
The female usually lays 3 eggs in a shallow open cup nest on a horizontal tree branch. The male defends a large area around the nesting territory. Both parents feed the young birds.
They wait on a perch at the top of a tree and fly out to catch insects in flight.
Song / Call:
The song is a whistled quick-three beers. The call is a rapid pip pip pip.
The numbers of this bird are declining, probably due to loss of habitat in its winter range.
Note on Taxonomy:
Contopus borealis is a junior synonym of Contopus cooperi, according to the 1997 AOU checklist, quoted by BISON. The name of this species is listed as Contopus borealis in many older guides.