English Name: common poorwill
Spanish Name: tapacamino tevíi
View all images of Phalaenoptilus nuttallii
This species is present in the Arizona-Sonora Desert Museum's live collection.
Common Poorwill (Phalaenoptilus nuttallii)
Poorwills have large eyes, tiny bills, huge gapes, and short legs. They (7-8½ inches; 17.5-21.5 cm) have rounded wings and no white bar.
Poorwills are found in all Sonoran Desert habitats. The Poorwill is more common on sparsely vegetated bajadas.
Poorwills are insect-eaters. A hunting Poorwill sits on open ground, looking up into the sky for the backlit silhouettes of large moths or beetles. When it spots something, it flutters up, usually no higher than ten feet, and catches the insect in its mouth. These birds are crepuscular, needing some light to hunt by. Poorwills like hunting by moonlight (they're lunarphilic) and on these nights they take over the niche of the lunar-phobic, insect-eating bat.
During the day, Poorwills rest on the ground or horizontally on a branch, well camouflaged by their cryptic coloration. During winter, Poorwills may migrate too. But they may also hibernate, greatly lowering body temperature, respiration, and heart rates for days, even months, at a time. This behavior is very unusual in birds — hummingbirds enter torpor, but only for one night. The first documented hibernating Poorwill was found in the Sonoran Desert, in a hollow in a rocky canyon. Its discoverer tried to find signs of life in this apparently dead bird by catching the condensation of its breath on a mirror, but failed. Ten days later, the bird still hadn't moved, but when the man touched it, the bird winked at him.
Nightjars are birds of mystery. Camouflaged in mottled brown and gray, they generally hide and sleep during the day, resting on the ground or on horizontal branches with their big eyes closed. At night they emerge to fly about, as silent in the air as the moths that they often capture in their wide, gaping mouths. Many nightjars are best known by, and named for, their nocturnal songs; the Whip-poor-will, which reaches the mountain forests of the southwest, is a good example.
Around rocky outcrops in the desert, the lonesome cry of the Poorwill is a familiar sound on summer nights, especially when the moon is bright. Naturalists who are out at night may find Poorwills sitting on roads, and may even be able to watch them hunt when the birds flutter up from the ground to catch passing insects. Poorwills mostly disappear from our region in winter, but they are not necessarily gone: these are the only North American birds known to hibernate, and they may sleep for days or even weeks at a time.