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Breeding Bird Atlas 2 Results
See all of the BBA2 data to date on the USGS BBA Explorer.
Preliminary Results:
Whip-poor-will: A Quiet Decline
Caprimulgus vociferus
Breeding Habitat: Open forest
Massachusetts Status: Declining
The reverberating cries of the Whip-poor-will have been an integral part of late spring and early summer evenings throughout Massachusetts.
As with all nightjars, Whip-poor-wills are often heard but seldom seen. It is mainly through voice that their presence in Massachusetts has been known since the arrival of the first European colonists.
The initial clearing of forest may have been beneficial to the whips, but unlike their nighthawk cousins, Whip-poor-wills seem to require fairly extensive contiguous forest tracts for nesting. Such tracts became hard to come by as more and more of Massachusetts’ forests disappeared, but the Whip-poor-will hung on. By the time Breeding Bird Atlas 1 (BBA1) came around, the forests had begun to regenerate in earnest.
In BBA1, the whip breeding population was scattered, but fairly widespread. The open forests of pitch pine and scrub oak that characterize the Cape & Islands have always been a bastion for Whip-poor-wills in Massachusetts. The open canopy and low stem density of this type of forest allows ample light to penetrate to the lower levels of the forest, where Whip-poor-wills do most of their feeding.
Cape Cod Forest
Unlike Common Nighthawks, which fly continuously while feeding, Whip-poor-wills usually sit and wait on the ground or a low branch, sallying forth to snap up insects and then returning to their perch to search for more prey. Without enough light to see by or enough room to fly, Whip-poor-wills cannot hunt. As a result, they are usually absent from mature mixed forest ecosystems. As forests across the Bay State mature and development spreads, the Whip-poor-wills are losing out.
The decline we’re seeing here is one of the most troubling kinds. No county has lost all of its whips, but just about everywhere – even Cape Cod – has lost some. Whip-poor-wills are disappearing all across the board. Certainly, forests are becoming older and the march of human civilization encroaches ever more into the wilderness. These things are not beneficial to the Whip-poor-will.
 There is likely more to the problem than simply loss of breeding habitat, though. There seem to be few refuges left to the Whip-poor-will. A decline in large insect prey (such as saturniid moths) may be a major factor. What we really need is the best data we can possibly get on our current breeding whips.
Whip-poor-wills return to our area in most years around the end of April and the beginning of May. By the end of May, most breeders have a clutch in the nest. The eggs hatch three weeks after being laid, and the young develop fairly quickly. They may explore the area around their nest within a week or two, and fledge around 20 days.
Whip-poor-wills are double-brooded in the southern parts of the range, but most of our Massachusetts breeders probably only produce one brood per season. The birds rely almost entirely on their camouflage to avoid predations while nesting on the ground, but the parents may use a broken-wing display as a last-ditch attempt to lead off threats that come too close.
Calling has usually ceased by the end of August, and before September ends these long-distance migrants will already have departed for Central America and the southern US.
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