Common Nighthawk (Carmacks BioBlitz)

Common Nighthawk

Chordeiles minor

Field identification ⁵

The common nighthawk is distinguished from other caprimulguids by its forked tail (includes a white bar in males); its long, unbarred, pointed wings with distinctive white patches; its lack of rictal bristles, and the key identifier – their unmistakable calls. These birds range from 21 to 25 cm (8.3 to 9.8 in) in total length and from 51 to 61 cm (20 to 24 in) in wingspan. Body mass can vary from 55 to 98 g (1.9 to 3.5 oz). Among standard measurements, the wing chord is 17.2 to 21.3 cm (6.8 to 8.4 in), the tail is 13 to 15.1 cm (5.1 to 5.9 in), the bill is 0.5 to 0.8 cm (0.20 to 0.31 in) and the tarsus is 1.2 to 1.6 cm (0.47 to 0.63 in).

The common nighthawk resembles both the Antillean nighthawk and the lesser nighthawk and occurs at least seasonally in the entire North American range of both of these species. The lesser nighthawk is a smaller bird and displays more buffy on the undertail coverts, where the common nighthawk shows white. Common nighthawks and Antillean nighthawks exhibit entirely dark on the basal portion of the primary feathers, whereas lesser nighthawks have bands of buffy spots. Common and Antillean nighthawks have a longer outermost primary conveying a pointier wing tip than the lesser nighthawk. The common nighthawk forages higher above ground than the lesser nighthawk and has a different call. The only reliable way to distinguish Antillean nighthawk without disturbance is also by the differences in their calls. Visually, they may only be distinguished as different from the common nighthawk once in the hand. Subtle differences are reported to be a challenge in field identification.

"cool facts" ⁶

On warm summer evenings, Common Nighthawks roam the skies over treetops, grasslands, and cities. Their sharp, electric peent call is often the first clue they’re overhead. In the dim half-light, these long-winged birds fly in graceful loops, flashing white patches out past the bend of each wing as they chase insects. These fairly common but declining birds make no nest. Their young are so well camouflaged that they’re hard to find, and even the adults seem to vanish as soon as they land.
On summer evenings, keep an eye and an ear out for the male Common Nighthawk’s dramatic “booming” display flight. Flying at a height slightly above the treetops, he abruptly dives for the ground. As he peels out of his dive (sometimes just a few meters from the ground) he flexes his wings downward, and the air rushing across his wingtips makes a deep booming or whooshing sound, as if a racecar has just passed by. The dives may be directed at females, territorial intruders, and even people.
The Common Nighthawk’s impressive booming sounds during courtship dives, in combination with its erratic, bat-like flight, have earned it the colloquial name of “bullbat.” The name “nighthawk” itself is a bit of a misnomer, since the bird is neither strictly nocturnal—it’s active at dawn and dusk—nor closely related to hawks.
Many Late Pleistocene fossils of Common Nighthawks, up to about 400,000 years old, have been unearthed between Virginia and California and from Wyoming to Texas.
Common Nighthawks, which have one of the longest migration routes of all North American birds, sometimes show up far out of range. They have been recorded in Iceland, Greenland, the Azores, the Faroe Islands, and multiple times on the British Isles.
The oldest Common Nighthawk on record was 10 years old.