Associated Species: Other species that may use habitat in a similar way and/or respond similarly to threats, management, and conservation activities include Gray Flycatcher and Juniper Titmouse.

Distribution: Black-chinned Hummingbirds summer in the western United States. The breeding range indicates avoidance of high mountains where spring arrives late. Their range traces that of the pinyon and/or juniper woodlands of the interior states and semi-arid lands of Pacific states. In Colorado, Black-chinned Hummingbirds are fairly common summer residents in the western valleys and lower mesas. These hummingbirds are uncommon in southeastern Colorado foothills and mesas (Andrews and Righter 1992). They are rare in the ring of pinyon-juniper around the San Luis Valley. Black-chinned Hummingbirds winter in all of Mexico except the southernmost part and the Yucatan Peninsula. Scattered winter reports come from south Texas and the northern Gulf Coast.

Habitat Requirements: Black-chinned Hummingbirds prefer open pinyon-juniper woodland and adjacent shrub and herb covered lands. Alternatives to pinyon-juniper habitat include lowland riparian woodland and tall riparian shrub, including Gambel oak. These hummingbirds also find acceptable habitat in suburban settings. Ornamental plantings such as trumpet vine and hummingbird feeders maintain local nesting populations and assist the migrating population. Important nectar plants for these birds include paintbrushes, scarlet gilia, penstemons, larkspurs, twist flower, plus some rare plants, including giant helleborine and Arapien blazingstar. Black-chinned Hummingbirds are attracted to the flowers that abundantly follow a fire. Wild tobacco is a favorite.

Ecology: Black-chinned Hummingbirds are pinyon-juniper woodland semi-obligates in their Intermountain breeding range. In mid April, the birds return from their shrubby winter ranges. By the first of May the males are performing their courtship-territorial pendulum-like flights. They usually place nests only 1 to 2 m (3-6 ft) from the ground on a drooping branch or in a fork of a tree or even sagebrush or tall weeds. They construct their nests of light-colored plant down from sources such as willow catkins, milkweed pods, and thistle flowers, and the resulting elastic, spongy cup is thickly coated and securely bound by spider webs. Foliose lichens may decorate the cup (Harrison 1979). The summer menu includes flower nectar for energy and small insects to round out nutritional needs. The young are fed mostly insects until fledging. These insects are caught by short chases from a perch. These hummingbirds may assist in the pollination of some rare plants such as golden columbine, Eastwood's monkey flower, and several penstemon species. Cowbird parasitism is not known (Bent 1953). Hazards other than frosty weather are many, but probably are not major mortality factors. These hazards include shrikes, bullfrogs, dragonflies, thistles, and large spider webs (Bent 1953).

Management Issues and Conservation Recommendations: Maintaining a healthy forb component in nesting and adjacent habitats contributes to a healthy nectar and insect food supply for hummingbirds. Livestock grazing can damage this component. Defer grazing in a rotation that has some pastures flowering at all times through the growing season. This should benefit the security of the forage resource for both livestock and hummingbirds.

The lowland riparian habitat of this species in and near residential and recreation sites is susceptible to mosquito control demands. The chemical treatment of pinyon-juniper woodland is more likely to be herbicides and limited. Chemical pest control programs should be limited and a last resort where hummingbirds are desired. Any chemical land treatment proposal should be checked for its hazards to wildlife.

The sizeable segment of Colorado residents, and also all those along the way to the winter grounds who hang hummingbird feeders, make a considerable enlistment pool from which help for the species can be solicited, from monitoring to improvements in feeding practices.

Status and Reasons for Concern: This species has a high conservation need locally and throughout its range, and Colorado has a high area responsibility with more than 20% of the breeding population. Between 1988 and 1997 an average of 11.4 BBS transects were run in Physiographic Area 87 (SE = 1.55). Black-chinned Hummingbirds were detected on an average of 40% of these transects. The BBS trend for 1969-1996 for Physiographic Area 87 does not show a significant annual rate of change (P = 0.36, n = 13 routes). Populations throughout their range are vulnerable to mechanical and chemical habitat disturbances. This species is monitored by MCB with point transects.

Biological Objective: The objective, based upon results of the MCB monitoring program, is to maintain an average of one pair per 30 hectares (about one detection per 10 or fewer miles of continuous-count transects) in woodland types within and below the pinyon-juniper zone.

Selected References: Andrews and Righter 1992, Bent 1953, Harrison 1979, Kingery 1998.