By Hee Kim
Geographic Range
Empidonax hammondii is most commonly found in the western parts of the United States and Canada. Empidonax hammondii or Hammond's flycatcher can be spotted from east-central Alaska all the way down to east-central California and north-central New Mexico. These birds live in mountain forests and prefer to live in closed canopy forests, where barely any light peaks through (Gillson 1997; The National Conservancy 1999). (Gillson, 1997)
Habitat
E. hammondii lives mostly in mature mountain forests. Large dense-canopy and open-understory forests are vital for this species to thrive (The Nature Conservancy 1999; Reader's Digest 1990).
Physical Description
E. hammondii on average range in height from 12.7-14.0 cm long. The male length is 14.0-14.6 cm with a wing size of 6.6-7.1 cm, a tail size of 5.8-6.4 cm, and a bill size of 1.3-1.5 cm. The female length is 13.3 cm with a wing size of 6.2-7.0 cm and a tail size of 5.5-6.1 cm. As youths, these birds are brownish colored with yellowish-brown wing bars. As adults, E. hammondii have grayish upper parts, whitish or yellowish wing bars, grayish throat, and a dark colored breast (Bailey 1920; Reader's Digest 1990).
Some key physical features:
endothermic 
; bilateral symmetry .
Reproduction
Breeding season occurs between early June and late July. E. hammondii females have 3-4 whitish or yellowish eggs and incubate the eggs for 12-15 days. They nest in Douglas fir, ponderosa pine, western larch, tanoak, white fir, grand fir, aspen, birch, and maple. They prefer forest sites with clumps of tall conifers with well-developed canopies. The nest is a cup of bark, plant fibers, pine needles, and twigs that is built 6-60 ft. above the ground. The young leave the nest 17-18 days after hatching (Gillson 1997; The Nature Conservancy 1999; Reader's Digest 1990).
Key reproductive features:
iteroparous ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous .
Behavior
A distinctive behavior of Hammond's flycatchers is their sound. The male's call note is "pip" and the female call note is "peek". The songs are made up of three rough phrases: "see-wit...bzurrp...bzeep". The three phrases have a similar pattern and the same vowel sounds. These distinctive vocalizations differentiate this species from those of the other Empidonax flycatchers. E. hammondii are more likely to be heard than seen. This is partly because E. hammondii prefer to be higher in the trees than other flycatchers, e.g. dusky flycatchers (Gillson 1997; Reader's Digest 1990).
Key behaviors:
motile .
Food Habits
E. hammondii mainly eats insects such as ants and flying insects. They prefer to search for flying insects in the center parts of tall conifers and aspens. The types of flying insects they eat are beetles, moths, and flies. Mostly, E. hammondii sit and wait for an insect to be in sight and then quickly move in for the kill, their beaks opening and quickly snapping shut. They then return to where they sat to wait for the next insect (Bailey 1920; Gillson 1997; Reader's Digest 1990; USGS 1998).
Economic Importance for Humans: Negative
Unknown
Economic Importance for Humans: Positive
Empidonax hammondii are a forest insectivore and may be crucial in controlling forest insect populations (The Nature Conservancy 1999).
Conservation Status
IUCN Red List: [link]:
Not Evaluated.
Cool, shady forests for nesting, roosting, and foraging are essential for keeping E. hammondii populations from extinction. This species is still commonly found in the Pacific Northwest. Timber harvest and fires can sometimes actually benefit Hammond's flycatcher if the forest understory is opened up while the canopy remains closed. The open understory spaces facilitate E. hammondii's flight. More research (e.g. on the effects of timber harvest) is needed about threats to the species (The Nature Conservancy 1999).
For More Information
Find Empidonax hammondii information at
Contributors
Hee Kim (author), University of California-Irvine.
Rudi Berkelhamer (editor), University of California at Irvine.
