Common Poorwill
At a Glance
In dry hills of the west, a soft whistled poor-will carries across the slopes on moonlit nights. Drivers may spot the Poorwill itself sitting on a dirt road, its eyes reflecting orange in the headlights, before it flits off into the darkness. This species is famous as the first known hibernating bird: In cool weather it may enter a torpid state, with lowered body temperature, heartbeat, and rate of breathing, for days or even weeks at a time. Science discovered this in the 1940s, but apparently the Hopi people knew it long before that: their name for the Poorwill means 'the sleeping one.'
All bird guide text and rangemaps adapted from by Kenn Kaufman漏 1996, used by permission of Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Category
Nightjars, Upland Ground Birds
IUCN Status
Least Concern
Habitat
Arroyos and Canyons, Desert and Arid Habitats, Fields, Meadows, and Grasslands, Forests and Woodlands, High Mountains, Shrublands, Savannas, and Thickets
Region
California, Northwest, Plains, Rocky Mountains, Southwest, Texas, Western Canada
Behavior
Erratic, Flap/Glide
Population
1.700.000
Range & Identification
Migration & Range Maps
Departs from northern part of breeding range in fall; migratory route and winter range of these birds not well known. In southwest, may be present all year, remaining torpid in cooler weather.
Description
7-8 1/2" (18-22 cm). Smaller and shorter-tailed than other nightjars. Mottled gray-brown, with white band across lower throat. Shows small white or buff tail corners in flight.
Size
About the size of a Robin, About the size of a Sparrow
Color
Black, Brown, Gray, White
Wing Shape
Rounded, Short
Tail Shape
Rounded, Short, Square-tipped
Songs and Calls
A mellow poor-will.
Call Pattern
Falling, Flat
Call Type
Odd, Whistle
Habitat
Dry hills, open brush. Various kinds of open dry terrain at low elevation in the west, including rocky mesas with scattered shrubs, washes and hills in Sonoran desert, scrubby areas in dry open pine forest. May be found in open grassland, but usually only around rocky outcrops.
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Behavior
Eggs
2. White, sometimes with a few spots. Incubation is by both parents, 20-21 days.
Young
Both parents feed young, by regurgitating insects. If nest site is disturbed, parents can move either the eggs or young to a new location. Downy young can move on their own by hopping or somersaulting across the ground. Age of young at first flight 20-23 days. May raise 2 broods per year.
Feeding Behavior
Forages mostly by sitting on the ground or on a low perch and making short flights upward to catch passing insects. Occasionally forages in longer, sustained flights. Does most foraging at dawn and dusk or on moonlit nights. Sometimes picks up insects (and possibly spiders) from ground.
Diet
Insects. Feeds mainly on night-flying insects, especially moths and beetles, also some grasshoppers, flies, and others. Insects up to one and a half inches long can be swallowed whole.
Nesting
Male calls at night in spring to defend territory and to attract a mate. Nest site is on ground, on bare open soil, rock, or gravel, sometimes on dead leaves or pine needles. Often shaded by a shrub or overhanging rock, and sometimes in secluded rock shelter. No nest built, although bird may make a slight scrape in soil. Same site may be used more than one year.
Climate Vulnerability
Conservation Status
Still widespread, and numbers probably stable.
Climate Threats Facing the Common Poorwill
Choose a temperature scenario below to see which threats will affect this species as warming increases. The same climate change-driven threats that put birds at risk will affect other wildlife and people, too.