Cryptic, crepuscular Lesser Nighthawk
Lesser Nighthawk caught in broad daylight
Every so often I get up early enough to see nighthawks hunting at the school yard swooping swift and silent just above the ground. Nighthawks hunt with their wide mouths open, scooping up moths and other large insects. Their wings flash like blades of a knife as they cut through the fading dark. On each dusky wing flares a crescent of white barring, like an insignia or a badge. The dog and I have also flushed these birds from the ground on a certain trail we frequent, and the other morning along a wash at the foot of South Mountain we came upon a nighthawk roosting. I took a picture, but you would call me crazy when I said yes, there is a bird sitting right there, right on that boulder! Roosting nighthawks look like a lump, and their brown, grey and white plumage blends perfectly with desert surroundings. The bird is a member of the nightjar family and shares with the others this cryptic coloring and crepuscular habit of hunting at dawn, dusk and by the light of a full moon. All nightjars have small beaks, tiny feet and little use for walking. They burst from lump into instant flight. The nighthawk in the wash flew a large circle and returned to the boulder, displaying another characteristic of sitting sideways on branches and boulders, so nothing hangs out to be observed by predators. They squint their large eyes to further reduce visibility and very rarely do they make a sound. One source I read referred to their call as a froglike trill and apparently they only trill during breeding season. They don’t build a nest, laying two eggs on the bare ground where the mom sits for about 20 days. The parents will mount an aerial attack on intruders. The nighthawk is found in open arid areas throughout the Southwest and into Central America. In the winters they chase the heat even further south to the tropics, sometimes migrating in groups called kettles. This mysterious bird copes well with extremes of temperature, employing a gular-flutter (similiar to a dog’s panting without the long tongue) for evaporative cooling in the searing heat. Caught in the cold when even the bugs are hiding out, the nighthawk survives by falling into a torpor much like hibernation. Yes, those quiet shy types are often most interesting!
Photo courtesy of Science Blogs