Birds
Whip-poor-will
Antrostomus vociferus · also called whip-poor-wills
A whip-poor-will calls its own name into the dark, over and over, sometimes hundreds of times without pause, from somewhere in the forest that remains impossible to pinpoint by sight. By day it sits motionless on bare ground or leaf litter, mottled plumage blending in so completely that most people who hear it nightly have never actually seen one.
Overview
The whip-poor-will, Antrostomus vociferus, is a nocturnal, ground-nesting bird found in deciduous and mixed forest across eastern North America. Its repetitive whistled call gave the species its name, and its camouflage makes daytime sightings genuinely rare.
A call louder than the bird is visible
Between its exceptional leaf-litter camouflage and its habit of nesting directly on bare ground, the whip-poor-will has built an entire identity around being heard rather than seen, a bird most people know only by its own repeated name.
Status
Near Threatened — declining across parts of its eastern North American range from a combination of habitat and insect-prey changes not yet fully understood.
Whip-poor-will: common questions
Why is the whip-poor-will named after its own call?
The whip-poor-will produces a loud, repetitive whistled call that closely resembles the words "whip-poor-will" spoken over and over, sometimes continuing for hundreds of repetitions in a row, and this distinctive vocalisation directly inspired the common name applied to the species long before detailed physical description became standard practice.
Why is a whip-poor-will so hard to see during the day?
A whip-poor-will has mottled grey, brown, and black plumage that closely matches forest leaf litter and bark, and because the bird also lays its eggs directly on bare ground without building a nest, both the adults and their eggs rely almost entirely on this camouflage to remain undetected by predators and observers alike.
Does the whip-poor-will's breeding really follow the moon?
In some populations, whip-poor-will breeding activity has been found to align closely with the lunar cycle, with nesting timed so that chicks hatch around the time of a full moon, a pattern researchers believe may be linked to the improved nighttime foraging conditions that increased moonlight provides for parents feeding their young.
Why is the whip-poor-will considered Near Threatened?
Whip-poor-will populations have declined across parts of their eastern North American range in recent decades, a trend likely connected to some combination of forest habitat changes and declining insect prey availability, though the exact combination of causes behind the decline is not yet fully understood by researchers.