This flycatcher has a robust body with a large head and a short tail. Adults of both sexes can grow up to 8 inches (20.3 cm) in length and weigh slightly over one ounce (28.3 g). The chest is white with dark grey coloring on the sides which gives the appearance of a vest. The back is a dark olive-brown.
The birds are from the Order Passeriformes, or perching birds, which are the most widely-distributed avian form in the world. Passerine birds are characterized by three forward-pointing toes and one backward, allowing them to effectively cling to or perch on branches.
Olive-sided Flycatchers can often be found perching on trees and shrubs in wooded areas waiting for insects such as bees. They pursue and eat these insects in mid-air. Nests are built in trees and snags, constructed out of twigs and lichens. The flycatchers will produce two to five eggs and will tenaciously defend their territory, chasing off other birds and squirrels which may threaten their young.
The Olive-sided Flycatcher can be found from Alaska through the western United States, mainly in coniferous forests and other wooded areas. During migration, they can be found as far south as Peru.
The bird has a large range but low density, which is a concern to biologists. The bird’s population has declined over 60% in the last few decades in its South American winter range due to habitat destruction.
Photo credit: USFWS