Hammond's Flycatcher, found in coniferous forests across the western United States and Canada, is distinguished by its small size, olive-gray plumage, and a distinct white eye-ring. Known for its distinctive 'peek' call, this species skillfully catches insects mid-air, contributing to insect population control in its ecosystem.

Empidonax hammondii, commonly known as Hammond's Flycatcher, is native to North America. Its geographical distribution includes western regions of the United States, parts of western Canada, and extends into southern Alaska. During the breeding season, it is primarily found in the mountainous areas of the western United States, including the Rocky Mountains, the Sierra Nevada, and the Cascades. In the non-breeding season, it migrates to Mexico and Central America, particularly in the highland regions.

Hammond's Flycatcher typically inhabits coniferous and mixed coniferous-deciduous forests. It is often found in cool, moist environments, preferring higher elevations ranging from 1,200 to 3,500 meters during the breeding season. The species favors mature forests with abundant understory for foraging.

As an insectivorous bird, Hammond's Flycatcher plays a critical role in controlling insect populations within its habitat. It often forages by catching insects in flight, a behavior known as 'hawking.' The species is adapted to exploit the vertical structure of forests, often seen flitting among the mid to upper levels of the forest canopy.