Your eyes drift up above the cityscape, and then you spot it — a bird dashing and diving through the white light. Its wings end in what seem like sharp points. Across each feathered span, a bar of white catches the ballpark lights with every flashing turn as it devours bugs attracted by the lights. This is the Common Nighthawk, a public servant that consumes mouthfuls of moths, mosquitoes, flies, beetles, maybe even mayflies hatching from the Allegheny.
The Common Nighthawk is neither common nor a hawk, but it is a welcome summer resident of Greater Pittsburgh. Nighthawks are like flying vacuum cleaners, their wide mouths sucking up every morsel of flying protein they can take out of the air. They zoom back and forth with deliberate wing beats that propel their nearly foot-long bodies in constant search of nourishment. This bird is visually mundane with a mix of dark brown, gray and white feathers, white chin and wing bars, and a tiny beak. But its flight is marvelous, high above the city at dusk with a nasal “peent” call that serves as an auditory marker of its lofty territory.
Though visible during the day or evening, Common Nighthawks tend to be crepuscular, preferring to forage among the lengthening shadows of a summer sky as they draw out into night. Once they arrive from their South American wintering grounds, the birds like the flat, gravel roofs of Pittsburgh, all the better to lay one, two, or three whitish eggs, dotted gray and brown to blend into the terrain. Green roof aficionados take heart: a patch of gravel four feet by four is probably enough for a breeding pair to set up housekeeping. The lack of such stony beds may be one reason for their declining population in the eastern U.S.
Besides the dwindling number of suitable roofs, their only real concern is a marauding murder of crows, which could steal their eggs or make a meal of their chicks. Think about the crowds of crows that call Pittsburgh home these days, and you’ll quickly realize that life is rough for the nighthawk. They might superficially resemble diurnal raptors, but they’re essentially defenseless, with stubby feet and a bill more like a thimble than a needle or hook. Easy pickings, but for their fantastic flight.
In the fall these birds will head south toward Panama or beyond, following food sources to warmer climes. But Pittsburgh offers a fine summer repast, especially as the rivers become cleaner and the bug populations find healthier habitats. Think of it this way: if Pittsburgh can host a major fishing tournament as it did in 2009, then what’s good for the bass is good for the nighthawk. Insects that make it out of the water and into the air are fair game for this inconspicuous but vigilant aerial predator.