Sunday, local bird watchers and nature enthusiasts alike will become citizen scientists for the night as part of “A Swift Night Out,” a national research project that counts and tracks Chimney Swifts as they migrate south for the winter.

The local count, led by Dan Graves, an environmental educator at the Urban Ecology Center, will begin at 6:45 p.m. on the playground behind St. Robert School, 2200 E. Capitol Dr.

Classified as “near-threatened” by conservationists, Chimney Swifts are a small bird known for its acrobatic flying. At dusk, they can be seen swooping down and almost free-falling vertically into their roost for the night.

The St. Robert pack has been roosting in the school's chimney for the past seven summers. While some roosts may consist of an extended family group of a half-dozen birds, larger sites can host hundreds of birds.

One previous count estimated more than 1,000 swifts in the St. Robert chimney.

Sunday's count is part of a national research project that collects counts from across the United States as the swifts migrate south to Peru for the winter. The data is used to track the birds' migration pattern, as well as help keep an accurate count of the Chimney Swift population.