SuAsCo/Nashua Rivers & Beyond Nighthawk Survey

Photo by Bill Schmoker. Look here for other great photos by Bill.

For almost one hundred years the population of Common Nighthawks has been declining in the Northeast for reasons that are not conclusively known. The purpose of the SuAsCo/Nashua Rivers and Beyond Survey is to count and record the annual fluctuations of migrating nighthawks in a defined area over time and create a longitudinal data set that might contribute to research on the long-term decline in abundance of this species.

The Common Nighthawk, contrary to its name, is most active at dawn and near dusk and is not a hawk but a member of the taxonomic family Caprimulgidae, which includes the Whip-poor-will. Nighthawks are insectivores and typically seen flying gracefully and powerfully, taking food on the wing with the smaller swallows and Chimney Swifts. Emergent swarms of flying ants are an especially attractive food for this species and our data suggest a connection between nighthawk migration routes and local flying ant days when these insects are aloft.

The Fall migration typically begins in early August and peaks during the last week of the month, diminishing rapidly in early September. During this stage of their long journey to South America the nighthawks roost during the day and take flight late afternoon until early evening, filling their stomachs as they go, and resting at nightfall. At this time they are most commonly spotted foraging over open fields, lakes, and rivers, individually or in gregarious flocks, some numbering in the hundreds or even thousands on rare occasions. They do not reliably move southward, often heading to other points or in apparently random directions, but always resuming a generally southward movement.

The most conspicuous field mark is a bold white blaze under the outer wing, but this bird is best identified from afar by its long, arched, falcon-like wings and the moderate tempo of its wingbeats that are often described as butterfly or bat-like.

Our present survey area extends from the Blackstone River headwaters in central Massachusetts north to the Concord, New Hampshire region and from the Connecticut River valley on the west to the Charles River basin on the east.

Survey volunteers choose their observation sites and when and how long they would like to spend time at their sites. The daily counts, comments, and related data are entered directly into the Data Entry section of this web site, which provides near real-time results of the sightings across our survey area. New volunteers are invited to create a user name and password and open an account.

If you have questions about this survey or this web site, or if you are interested in participating, please send email to This e-mail address is being protected from spambots. You need JavaScript enabled to view it