Common Poorwill

The common poorwill was illustrated and formally described in 1844 by the ornithologist John James Audubon from a male specimen collected on the eastern bank of the Missouri River between Fort Pierre and mouth of the Cheyenne River in South Dakota. Audubon coined the binomial name Caprimulgus nuttallii, choosing the specific epithet to honour his friend, the ornithologist Thomas Nuttall. The species was moved to its own genus Phalaenoptilus by the American ornithologist Robert Ridgway in 1880. The genus name combines the Ancient Greek meaning "moth" and meaning "plumage". Six subspecies are recognised: * P. n. nutalli (Audubon, 1844) – breeds over most of the North American range. * P. n. californicus Ridgway, 1887 – dusky poorwill, is darker and browner than the nominate race. It occurs in western California and north Baja California * P. n. hueyi Dickey, 1928 – desert poorwill, is paler than the nominate race. It occurs in southeast California, southwest Arizona (USA) and northeast Baja California * P. n. dickeyi Grinnell, 1928 – San Ignacio poorwill, is smaller and less heavily marked than californicus. It is resident in southern Baja California. * P. n. adustus Van Rossem, 1941 – Sonoran poorwill, is paler and browner than the nominate race. It occurs from extreme southern Arizona to north Mexico. * P. n. centralis Moore, RT, 1947 – central Mexico

The common poorwill is the only bird known to go into torpor for extended periods (weeks to months). In 1804, Meriwether Lewis observed hibernating common poorwills in North Dakota during the Lewis and Clark Expedition. Though these observations were recorded carefully in Lewis's journal, their significance was not understood. This was at least in part because the common poorwill was not then recognized as a species distinct from the whip-poor-will of eastern North America. Native Americans of the Hopi tribe were likely aware of the poorwill's behavior even earlier — the Hopílavayi name of this bird, hölchko, means "The Sleeping One".

Breeding is from March to August in the south of the range, and late May to September further north. The nest of the common poorwill is a shallow scrape on the ground, often at the base of a hill and frequently shaded partly by a bush or clump of grass. The clutch size is typically two, and the eggs are white to creamy, or pale pink, sometimes with darker mottling. Both sexes incubate for 20–21 days to hatching, with another 20–23 days to fledging. There is usually one brood per year, but females may sometimes lay and incubate a second clutch within 100 m of the first nest while the male feeds young at the first site. The young are semiprecocial. An adult disturbed on the nest tumbles and opens its mouth, hissing, apparently imitating a snake.

Like other members of this family it feeds on nocturnal insects such as moths, beetles, and grasshoppers. It ejects pellets of the indigestible parts, in the manner of an owl. The common poorwill frequently takes prey off of the ground or by leaping into the air from the ground. It is reported to drink on the wing.