On my visit to South Platte Park this morning, I encountered 30 species of birds. Yellow warblers were especially common, joined by a fair number of yellow-breasted chats, gray catbirds and spotted towhees. But the highlight of my visit was provided by two black-chinned hummingbirds.
Summer residents throughout most of the Western U.S., these hummingbirds are best identified by their black throat (fringed by an iridescent purple swath along its lower edge), a white upper chest band, a white spot behind each eye, an emerald back and dusky flanks speckled with green. Like many other hummingbirds, they tend to perch on a dead snag between feeding forays. Unlike the broad-tailed hummingbird, which is a common summer resident along the Front Range, their wings produce a low pitched and rather subdued sound as it zooms about.
Black-chinned hummingbirds favor semi-arid pine-juniper woodlands on their breeding grounds but often visit open riparian woodlands during migrations. Here along the Front Range, they are primarily migrants, stopping to feed on nectar and insects before heading for breeding areas in Western Colorado and across the Intermountain West. Come September, most head for Mexico though an increasing number have been wintering along the U.S. Gulf Coast.