In the North we see them in summer, in small flocks flying at dusk and dawn: nighthawks seining the air for insects. The birds are sooty gray. White bandage-like markings on their long narrow wings flash as they swoop and stunt.
Nighthawks’ calls are short and nasal. Thoreau thought it sounded like they were “squeaking” and remarked in his journal on the birds’ “peculiar flitting, limping kind of flight.” The male nighthawk also has an intriguing courtship or territorial flight: He dives toward the ground, then pulls up suddenly so that his wings produce what one modern field guide calls “a humming, whooshing hoooov.” You feel the sound in your chest as much as you hear it with your ears.