Eastern Whip-poor-will

The Eastern Whip-poor-will is far more often heard than seen, and over the last few decades the number of people who have heard one has declined dramatically. “Where are all the whip-poor-wills?” is not an uncommon question posed to bird biologists in New Hampshire! Because they’re nocturnal, whip-poor-wills are hard to monitor, and most data come from broad surveys such as Breeding Bird Atlases. When Atlases conducted in the 1980s were repeated 20 years later, they discovered a roughly 50% decline in the area where whip-poor-wills occurred, largely reflecting public perception of the species’ plight. The need for more detailed data led to a specialized monitoring protocol, and at least in New Hampshire it appears that local populations may be starting to rebound.

The fall and rise in whip-poor-will fortunes is still a matter of some debate, but much speculation has centered on changes to habitat. Whip-poor-wills require open areas for foraging and forested areas for nesting and tend to thrive in edge habitats or open forests such as pine barrens. Such habitats were widespread during New England’s agricultural heyday but have since grown back into forest or been lost to development.

Early successional species in general are a great example of the adage “if you build it, they will come,” and are adapted to find and colonize ephemeral patches of shrubland that result from fire, logging, or other types of disturbance. It thus stands to reason that the recent uptick in whip-poor-wills could be the result of increased early successional habitat, either from management for species like woodcock and grouse or increased private timber harvests. Whatever the cause, it appears that whip-poor-wills have earned something of a respite, and while they’re not likely to become as common as 50 years ago, they might not be at quite as much risk as we once thought.

As usual for migratory species, the breeding season is only half the story. Whip-poor-wills migrate to Mexico and Central America for the winter, and habitat loss is an issue along their entire migratory route. New data from a tracking study suggest they also avoid areas with high light pollution on migration, which brings up another potential threat: changes to their food supply. There has been much discussion in recent years of declining insect population, with declines in large prey such as some moths and beetles being potentially important to nightjars such as whip-poor-wills. Light pollution, pesticides, and habitat changes could all be impacting these insects, and by association the birds that feed upon them.