Willow Flycatcher

The Willow Flycatcher, Empidonax traillii, is a modestly plumaged bird of the Tyrant Flycatcher family. It is a small, neotropical migrant with brown-olive upperparts, which are darker on the wings and tail, and whitish underparts. The bird is adorned with an indistinct white eye ring, white wing bars, and a small bill. The breast is tinged with olive-gray, and the bill features a gray upper part and an orangish lower part.

Identification Tips

Adult Willow Flycatchers measure between 130–150 mm in length, with a wingspan of approximately 220 mm. They weigh around 13.5 g. The wing length ranges from 68.7–75.6 mm, the tail from 54–64.5 mm, the culmen from 10.5–12.3 mm, and the tarsus from 15.5–18.0 mm. These measurements can aid in distinguishing them from similar species.

Habitat

These birds favor deciduous thickets, particularly those dominated by willows, and are often found near water. They construct a cup nest in a vertical fork of a shrub or tree.

Distribution

The Willow Flycatcher breeds across the United States and southern Canada. It is a migratory species that winters in Mexico and Central America, with some venturing as far south as Ecuador in South America.

Behaviour

The Willow Flycatcher migrates impressive distances, ranging from 1,500–8,000 km between its wintering and breeding grounds. It is known for its sneezed "fitz-bew" song and a dry "whit" call.

Song & Calls

The song of the Willow Flycatcher is a distinctive "fitz-bew," which is crucial for identification, as it is the only reliable method to distinguish it from the Alder Flycatcher in the field. Its call is a dry "whit."

Breeding

Breeding occurs across a range of elevations, from near sea level to over 2,600 meters in certain areas. The nest is a cup shape, situated in a vertical fork of a shrub or tree.

Similar Species

The Alder Flycatcher (Empidonax alnorum) is very similar in appearance to the Willow Flycatcher, and they were once considered a single species. The two can be reliably separated by their distinct songs.

Diet and Feeding

Willow Flycatchers are insectivorous, feeding on a variety of insects including common hoverflies. They typically forage from a perch, flying out to catch insects in flight, and may also hover to pick insects from foliage. Occasionally, they may consume berries.

Conservation status

The IUCN lists the Willow Flycatcher as Least Concern. However, the Southwestern subspecies, E. t. extimus, is federally endangered and faces threats from habitat loss and alteration, as well as competition from invasive plant species such as saltcedar. Conservation efforts, including habitat restoration and management, are in place to support this subspecies.