The eastern whip-poor-will (Antrostomus vociferus) is a medium-sized bird belonging to the nightjar family (Caprimulgidae). It is known for its distinctive nocturnal habits and the onomatopoeic "whip-poor-will" call, which is frequently heard across its range. While often heard, this cryptically plumed nightjar is seldom seen due to its excellent camouflage. The species breeds from Saskatchewan to the Maritimes, down the eastern seaboard to northern Georgia, then west to Kansas and into Minnesota, with wintering grounds extending to the southeastern states, eastern Mexico, and Central America.
Habitat and Distribution
Eastern Whip-poor-wills breed in dry deciduous or evergreen-deciduous forests with little or no underbrush, close to open areas. The forest types they use include pine-oak with juniper, pine plantations, pine flatwoods, northern hardwood forests, low-elevation white pine, oak, aspen, birch, and scrubby woodlands with pitch pine, scrub oak, and hickory. They seem to avoid large tracts of uninterrupted forest with dense canopy. Their migration habitat is similar to their breeding habitat. In winter, Eastern Whip-poor-wills prefer broadleaf tropical or subtropical forest near open areas.
In Massachusetts, whip-poor-will distribution appears to be closely correlated with fire-adapted landscapes such as pine barrens and oak glade communities. The primary habitats currently supporting whip-poor-wills in Massachusetts are barrens, oak glades, power line corridors, abandoned gravel operations, and logging operations.
Foraging Behavior
Eastern Whip-poor-wills are strictly nocturnal birds, most active at dawn and dusk and on bright, moonlit nights. They start foraging approximately 30 minutes after sunset and continue until darkness impedes their vision. They resume feeding at first light, stopping about 40 minutes before sunrise. When the moon is sufficiently bright, they may hunt all night. However, they will not forage during cold, rainy weather.
These birds perch in trees, or sometimes on the ground, and make short sallies to snag insects up to 15 feet off the ground, or they may stay out on longer insect-catching flights. In flight, whip-poor-wills are slow and silent, appearing moth-like, often hovering and flying erratically in pursuit of flying insects. The birds fly silently into open areas, such as grasslands or farms, in search of insects. Whip-poor-wills appear to time their nesting so that chicks will hatch about 10 days before the full moon, when the parents have more time (and moonlight) to catch food for them.
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Dietary Composition
Eastern Whip-poor-wills feed exclusively on insects, making them insectivores. Their diet consists of a variety of insects, including:
- Moths (especially medium-sized moths from families Noctuidae, Geometridae, Erebidae)
- Scarab beetles
- Click beetles
- Long-horned grasshoppers
- Stoneflies
- Ground beetles
- Carrion beetles
- Tiger moths
- Ants
- Bees
- Wasps
- Fireflies
- Long-horned beetles
- Measuringworm moths
- Owlet moths
- Weevils
- Scavenger beetles
The primary diet of whip-poor-wills is large moths and night-flying beetles. Their enormous mouths allow them to swallow insects up to two inches long. They sometimes search rotten logs and leaves for ants, caterpillars, beetles, worms, and other insects. To do this, whip-poor-wills rely upon their large eyes and moonlight to feed on the backlit moths.
Feeding the Young
Adults feed young by regurgitating insects. Nest initiation typically occurs so that chicks hatch around a full moon, apparently to allow parents to maximize their hunting opportunities. The chicks are fed regurgitated insects.
Declining Insect Populations and Conservation Concerns
Declines in insect populations due to pollution and pesticide use have affected this insect-eating bird. Whip-poor-wills have been recorded arriving in Massachusetts from their wintering grounds as early as mid-April, with pairs formed soon after and two eggs laid directly on the forest floor by mid-May. Whip-poor-will pairs are thought to be monogamous, at least through a single breeding season, and both members of the pair share the three weeks of incubation duties, followed by three weeks of brooding and feeding flightless chicks at the nest site. Chicks are able to feed themselves once they leave the nest, but parents have been observed feeding fledglings, and it is thought that family units associate with each other until their autumn migration, which in Massachusetts can be as late as the end of September. The importance of predation by native predators as a factor limiting reproductive success and adult survival is also poorly understood. It is unlikely that whip-poor-will will be able to reclaim its former distribution across Massachusetts because many former haunts have been rendered uninhabitable due to permanent habitat loss and/or degradation. Instead, conservation should focus on protecting, restoring and managing existing whip-poor-will habitat across the state. Coordinating with land managers, landowners and foresters to ensure that existing whip-poor-will habitat remains viable is key in stabilizing the state’s population.
In Illinois, preliminary research suggests that to help whip-poor-wills we need to help moths. Actions such as planting native plants, maintaining unmanicured areas for moth populations to overwinter, and reducing the use of pesticides may benefit both moths and whip-poor-wills. The decline of whip-poor-wills has not only been noticed in Illinois but has attracted the attention of researchers across North and Central America.
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Threats and Conservation Status
The Eastern Whip-poor-will is currently in decline. The 2025 State of the Birds report lists Eastern Whip-poor-will as a Yellow Alert Tipping Point species, meaning that it has lost more than 50% of its population in the past 50 years but has relatively stable recent trends. The BBS estimates that Eastern Whip-poor-will numbers have declined by 1.8% per year between 1966 and 2023, resulting in a cumulative decline of 66% over that period. Partners in Flight estimates a global breeding population of 1.8 million individuals and rates the species 14 out of 20 on the Continental Concern Score.
The main threats to the Eastern Whip-poor-will include:
- Loss of open-understory forests due to conversion of forest to crops, pasture, urbanization, or fire suppression leading to dense understories.
- Collisions with cars, as they often fly over roads or sit on roadways while foraging.
- Declines in prey insects from pollution and pesticide use.
The species was listed as special concern under the Massachusetts Endangered Species Act in 2011 and as Threatened in Vermont in 2011.
Habitat Management
Active restoration and management of whip-poor-will habitat depends upon reintroducing a disturbance regime to the landscape. Over the last several years we have noticed more whip-poor-wills in forests that have been managed via prescribed burns, invasive species removal, and selective tree removal. In contrast, forests that have become dense due to invasive species appear to have few or no whip-poor-wills.
Cultural Significance
Due to its song, the eastern whip-poor-will is the topic of numerous legends. A New England legend says the whip-poor-will can sense a soul departing, and can capture it as it flees. Native American lore considered the singing of these birds a death omen. The Whip-poor-will was recently separated into two species based on differences in DNA. Whip-poor-wills have a reflective structure behind their retina called a tapetum lucidum.
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