The Olive-sided Flycatcher (Contopus cooperi) is a medium-sized bird, measuring about 7 inches in length and weighing around 1 ounce. These birds have distinct field marks that make them easy to identify. They have a large, triangular head with a short neck, a straight bill, and a stocky build. Their plumage is primarily grayish-brown, with a pale belly and two white patches on their sides that resemble vestigial pockets. Males and females look alike, although males tend to be slightly larger.
One of the most distinctive features of the Olive-sided Flycatcher is its call, which is a loud, clear whistle that sounds like “quick-three-beers.” They use this call to establish their territory and attract mates. These birds are primarily found in open woodlands, particularly those with tall trees and nearby bodies of water, such as lakes or streams.
The Olive-sided Flycatcher is a migratory bird that breeds in the boreal forests of North America and winters in Central and South America. They begin their migration south in August and September, flying thousands of miles to reach their wintering grounds. During the breeding season, these birds are solitary and territorial, but they can be found in small groups during migration.
Olive-sided Flycatchers feed primarily on flying insects, which they catch in mid-air. They also occasionally eat berries and small fruits. These birds are known for their “perch-and-wait” hunting style, where they sit on a high perch and watch for prey before swooping down to catch it.
Unfortunately, the Olive-sided Flycatcher has experienced significant population declines in recent years, and it is currently listed as a threatened species under the Endangered Species Act. Habitat loss and fragmentation, particularly in its breeding grounds, are the primary threats to this species. Conservation efforts are underway to protect the forests and wetlands that these birds rely on for breeding and migration.