The Willow Flycatcher (Empidonax traillii) is a small passerine bird found in North and Central America. This species is about 5.5 inches long and weighs approximately 0.4-0.5 ounces. Its wingspan ranges from 7.5 to 8.5 inches. The Willow Flycatcher has a slightly rounded head and a short tail. It has an olive-green back, wings, and tail, with a yellowish-white belly. The flycatcher has a distinctive white eye-ring and a broad, pale-grayish eyebrow. The bill is short, broad, and black, with a slightly hooked tip.

The Willow Flycatcher can be identified by its distinctive “fitz-bew” call, which is often heard before the bird is seen. It also has a habit of flicking its wings and tail, which can help distinguish it from similar-looking flycatcher species. During migration, this species can be found in a variety of habitats, including riparian areas, wetlands, and shrubby fields. In the breeding season, the Willow Flycatcher is found in willow and alder thickets, often near water.

The Willow Flycatcher is a migratory bird, breeding in western North America and wintering in Mexico, Central America, and northern South America. The northern population migrates to southern California, the southwestern United States, and Mexico. The eastern population breeds in the Great Plains, Great Basin, and the Midwest, and migrates to Central and South America. The Willow Flycatcher faces threats from habitat loss and fragmentation, as well as brood parasitism by the Brown-headed Cowbird.

The Willow Flycatcher is a insectivorous bird that feeds mainly on flying insects, such as flies, moths, and beetles. It perches on low branches or twigs and flies out to catch its prey in mid-air. It also occasionally feeds on spiders and berries. The Willow Flycatcher builds a cup-shaped nest made of grasses, leaves, and bark strips, usually placed in a shrub or sapling near water. The female lays 3-4 eggs, which are pale cream with brown and gray spots, and incubates them for about 12-14 days. The young fledge after about 14-16 days.

In conclusion, the Willow Flycatcher is a small bird with distinctive olive-green and yellowish-white plumage, a white eye-ring, and a broad, pale-grayish eyebrow. It is about 5.5 inches long, weighs approximately 0.4-0.5 ounces, and has a wingspan of 7.5-8.5 inches. The Willow Flycatcher is a migratory bird that breeds in western North America and winters in Mexico, Central America, and northern South America. During migration, it can be found in a variety of habitats, including riparian areas and wetlands. The species feeds mainly on flying insects and builds its nest in shrubs near water.