Tree Swallow

Steve Forman photographed these tree swallows in Grafton.

Steve Forman photographed tree swallows at Breakneck Hill Conservation Land in Southborough.

Steve Forman photographed tree swallows at Breakneck Hill Conservation Land in Southborough.

Steve Forman photographed these tree swallows at Breakneck Hill Conservation Land in Southborough.

Cindy Winer photographed a tree swallow at Mass Audubon's Broadmoor Wildlife Sanctuary in Natick.

Eric Crockwell photographed a beaver, a cotton-tailed rabbit, a tree swallow, and white-tailed deer along the Sudbury Reservoir Trail, part of the Boroughs Loop Trail, in Southborough.

Gail Sartori photographed tree swallows and bobolinks at Heard Farm in Wayland.

Nancy Wright photographed a great blue heron and a tree swallow at the Wayne F. MacCallum Wildlife Management Area in Westborough.

Steve Forman photographed tree swallows at Hager Pond in Marlborough.

Steve Forman photographed an orange sulphur, a ruby-throated hummingbird, a barn swallow, a blue dasher, an eastern tailed-blue, European starlings, house finches, a house sparrow, a red-winged blackbird, a tree...