Perception Channels: visual ; tactile ; acoustic ; chemical
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).
IUCN Red List of Threatened Species: least concern
Unknown
Empidonax hammondii are a forest insectivore and may be crucial in controlling forest insect populations (The Nature Conservancy 1999).
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).
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).
Biogeographic Regions: nearctic (Native )
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).
Terrestrial Biomes: forest ; mountains
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).
Other Physical Features: endothermic ; bilateral symmetry
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
Hammond's flycatcher (Empidonax hammondii) is a flycatcher in the family Tyrannidae. This small insectivorous bird inhabits the coniferous and mixed forests of western North America. The name of this bird commemorates William Alexander Hammond who was the surgeon general of the US Army. Hammond collected bird specimens for Spencer Fullerton Baird.[2]
Adults are 12–14 cm long (4.7-5.5 in), span about 22 cm (8.7 in) across the wing and weigh 8-12 g (0.3-04 oz).[3] They have grayish-olive upperparts, darker on the wings and tail, with whitish underparts; they have a conspicuous white eye ring, white wing bars, a small bill and a short tail. The breast is washed with grey and the sides of the belly with yellow. Female usually have a shorter, wider bill compare with male's.[4] Immature are similar to adults, but have broader wing bars and are more buff.
Many species of Empidonax flycatchers look closely alike. Hammond's flycatchers are mainly confused with Dusky (E. oberholseri) and Gray (E. wrightii) flycatchers, which are similar in color and size and have an overlapping range.[5] The best way to distinguish the Hammond's flycatcher is by its call, breeding habitat and/or range.
Hammond's flycatchers are part of the genus Empidonax, which includes a dozen of other species. Despite the relatively large range of the species, the Hammond's flycatcher does not present a lot of genetic variations. This might be the result of a bottleneck event, that could have occurred when the species range was confined to the South of the Pleistocene ice. The bird's morphology, including its plumage, is also consistent across its range.[6] However, there are evidence showing that some Hammond's flycatcher on Vancouver Island, in British Columbia, have evolved longer, thicker bills in the absence of Western flycatchers, which occupy a very similar niche but usually has a thicker bill than the Hammond's flycatcher.[4] The Hammond's, the Dusky and the Gray flycatchers are sister species, with no evidence of interbreeding.[7]
The Hammond's flycatcher is a migratory species, breeding in Western North America and wintering in Mexico and Central America.[3]
Their preferred breeding habitats are mature coniferous and mixed forests. They are typically found in dense fir forests, conifer and aspen forests and dogwood.[5] Their habitats on wintering grounds are similar to the ones used as breeding grounds.
Hammond's flycatchers can be found in the Western United States, including Montana, Wyoming, California, Nevada, Utah, Arizona, New Mexico and Colorado.[5] In Canada, their range include British Columbia, Yukon and Alberta. Certain birds have been found as far North as Alaska. Overall, their breeding range is formed by regions that have been greatly influenced by past glaciation events.[6] These birds are migratory and winter in Mexico and in Central America.
The song is a multi versed hoarse ssilit, greeep, silit, pweet. The call is a sharp peek.
Hammond's flycatchers do not sing during the fall migration or on wintering grounds.[5] They start singing in early May, shortly after their arrival on breeding grounds. The frequency of the song is usually higher at the beginning of the mating season and drops as summer progresses; males that do not have a partner sing more often and at a higher frequency than paired males.[5]
Like in other species of the genus Empidonax, bill snapping and mandibles clicking are commonly used in a threatening context.[5]
Their favorite preys include beetles, flies, bees, butterflies and moths, with a mean length of 5.7 mm and a mean weight of 1.656 mg.[8] True beetles, and net-winged insects can also be part of their diet. They wait on an open perch high or in the middle of a tree and fly out to catch insects in flight, (hawking), also sometimes picking insects from foliage while hovering, (gleaning).
These birds are believed to be monogamous and show no evidence of extra-pair copulation.[5] Male Hammond's flycatcher physically fight at the beginning of the breeding season, locking themselves together in midair and fluttering to the ground.[9] They tend to nest on high, small to medium-sized branches of tall trees. They also prefer areas where they can be covered by leaves, on the northeast or southwest sides of trees. Finally, they prefer old-growth forest, with a minimum age of 80 to 90 years.[10]
They make a cup nest on a fork in a tree. Females usually lay in early June three or four creamy white eggs, sometimes marked with small reddish-brown dots.[3] The female incubates the eggs for about 15 days.[5] The hatchlings are altricial; both the male and the female are responsible of feeding the young.
Hammond's flycatcher (Empidonax hammondii) is a flycatcher in the family Tyrannidae. This small insectivorous bird inhabits the coniferous and mixed forests of western North America. The name of this bird commemorates William Alexander Hammond who was the surgeon general of the US Army. Hammond collected bird specimens for Spencer Fullerton Baird.