<trp-post-container data-trp-post-id='359821'>Least Flycatcher

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Migratrice
  • Scientific Name: Empidonax minimus
  • Spanish Name: Mosquerito mínimo
  • Famille : Tyrannidae
  • Known Nicknames: Chebec, Least Flycatcher
  • Average Length: 12–14 cm / 4.7–5.5 in
  • Average Weight: 10–12 g / 0.35–0.42 oz
  • Wingspan: 20–22 cm / 7.9–8.7 in
  • Key Feature: Prominent white eye ring and two pale wing bars
  • Régime alimentaire principal : Principalement insectivore
  • Range: Breeds in southern Canada and northern United States; winters in Mexico and Central America
  • Habitat: Open deciduous woodlands, forest edges, and riparian areas
  • Social Structure: Solitary or Pairs during breeding; loosely migratory
  • Nesting/Breeding: Cup nest in tree fork or branch
  • Statut de conservation : Préoccupation mineure (LC)
  • Évolution démographique : Stable

The Least Flycatcher (*Empidonax minimus*) is a tiny, energetic songbird that lives up to its name as the smallest member of its challenging genus in North America. Weighing less than a quarter, it sports a subdued olive-brown back, whitish underparts, and two distinct pale wing bars, with a notable white eye-ring that gives it a slightly surprised expression. Its most unique characteristic is its sharp, two-part "che-bek" call, which it repeats tirelessly from exposed perches in deciduous forests, serving as its primary identification tool since it looks nearly identical to other *Empidonax* flycatchers. A special feature is its aggressive territorial behavior during breeding season, where it fearlessly chases much larger birds away from its nest, proving that the smallest flycatcher has the biggest attitude.

Faits amusants

Despite its tiny size, the Least Flycatcher is a feisty bully, often aggressively chasing much larger birds like Blue Jays and American Robins out of its nesting territory. It is famous for its repetitive, two-part “che-bek” call, which it delivers incessantly from dawn to dusk during breeding season. One of its most unique adaptations is its nest-building strategy: it frequently places its small, cup-shaped nest directly in the fork of a shrub or tree, sometimes reusing the same branch for multiple seasons. Oddly, it also has a habit of “hover-gleaning,” where it will briefly hover in mid-air to pluck an insect off a leaf rather than catching it in a full aerial sally.

Habitats et répartition

The Least Flycatcher breeds across much of southern Canada and the northern United States, from the Maritime provinces and New England westward through the Great Lakes region and the northern Plains to central British Columbia and southern Yukon. Its breeding habitat is strongly associated with open, semi-open deciduous or mixed woodlands, particularly favoring edges, clearings, and second-growth forests with a sparse understory and an open canopy. It is also common in aspen groves, riparian corridors, orchards, and suburban parks with tall shade trees. During migration, it occupies a broader range of wooded habitats, including scrub and forest edges. Its wintering grounds extend from southern Mexico through Central America to northern South America, where it inhabits tropical lowland forests, forest edges, and secondary growth.

Comportements & Reproduction

The Least Flycatcher is a socially monogamous, territorial passerine. Males arrive on breeding grounds first and establish territories through persistent, repetitive "che-bek" calls and aggressive chases, often returning to the same site annually. Pairs form quickly upon female arrival, with courtship involving the male performing short, fluttering flights and feeding the female. The female builds a compact, cup-shaped nest in a tree fork, usually within 3–15 meters of the ground, using plant fibers and spiderwebs. She lays 3–5 creamy eggs with brown speckles and incubates them alone for 12–15 days, while the male guards the territory and brings food. Both parents feed the altricial young, which fledge at 13–16 days. A unique reproductive strategy is their aggressive, almost colonial territoriality: while they defend individual feeding territories, nests are often clustered in loose aggregations, a rare behavior among *Empidonax* flycatchers, possibly to enhance predator mobbing efficiency. They typically raise a single brood per season, but may renest if the first fails.

Alimentation

The Least Flycatcher is an insectivorous bird, with its diet consisting almost entirely of small flying insects such as flies, mosquitoes, moths, beetles, and wasps, which it captures in mid-air during short, agile flights from a perch. Interestingly, it employs a "hover-gleaning" technique, where it hovers briefly to pluck insects off leaves or bark rather than solely relying on aerial hawking. During the breeding season, it may also consume small spiders and caterpillars, and in late summer, it occasionally supplements its diet with small berries, like those from elderberry or dogwood, though insects remain its primary food source year-round.

Couleurs

The Least Flycatcher has olive-gray upperparts, a whitish throat and belly, and two distinct pale wing bars. Its most unique marking is a prominent white eye ring, often described as "spectacled," with a narrow, pale yellow wash on the lower belly and flanks. This subtle, countershaded coloration provides effective camouflage in dappled light among deciduous trees and shrubs.

Distribution Map

Places linked to this species. A sighting is never guaranteed.