There are a couple of local spectacles happening in the bird world during these final weeks of summer. The egret and heron roost off Route 1 in Salisbury continues to attract crowds each evening as upward of 400 egrets, both great and snowy, descend upon the trees around a small pond just off the road. Small numbers of great blue, little blue, green, black-crowned and yellow-crowned night herons have also used this roost in recent weeks. The egrets and herons start arriving in early evening, and their numbers continue to build past sundown. Wood ducks, mergansers, kingfishers and other birds are adding to the show.

     If you go to see this event, DO NOT park on Route 1! Parking on a state highway is prohibited, and $75 tickets are being issued. Pull in off the road and walk the small path to the edge of the pond.

     This is also the time of year when the swallows congregate on Plum Island. Their numbers will continue to build as they gather and feed in preparation for their journey south. Clouds of swallows will fill the sky, and every cattail in the marsh will have a swallow perched on it as they roost for the night. Doug Chickering of Groveland describes this spectacle well.

     “Even as I sat on our deck in Groveland, looking up into the endless blue sky above me, I could see tree swallows. Usually when I sit out in the evening I might see one or two tree swallows. Many times I see none. They used to be more common here on summer evenings but no more. Yet tonight there were tree swallows. Several tree swallows. They glided and fluttered in the wind, sometimes right above me, and sometimes near the horizon of trees. Some no more than a hundred feet and above that through layers almost out of sight. There were not really many of them; maybe a dozen or perhaps a score with a few barn swallows mixed in. I saw them mostly to the east and could not help but conclude that my tree swallows in Groveland were the outer wash of the huge gathering of tree swallows at Plum Island.

     “August dwindles away, the greenheads vanish, the peep sandpipers numbers crest, the first smatterings of passerines emerge, and the tree swallows gather at Plum Island. There are many events in the movement and lives of birds that are truly spectacular. This is one of them.

     “Earlier today (Saturday, Aug. 18) Lois Cooper and I were on the island. The winds were blustery and because it was low tide, the shore birds were few. Not much to look at; except for the tree swallows. From the gate to Hellcat the tree swallows were riding the winds in various numbers, sometimes scattered above the dunes, sometimes filling the air right above your head and sometimes punishing a bayberry or honeysuckle bush by the side of the road in a massive frantic feeding frenzy, that was almost frightening in its intensity.

     “I remember one Labor Day, a long time ago, when the tree swallows gathered almost beyond counting. Down the entire length of the island, the tree swallows were always present and flying, sometimes in dense swirling flocks; and sometimes in huge feeding roosts, and sometimes spread in carpets across the road. They stopped traffic, and people simply stood in awe of what they are seeing. I remember Dick Forster, who was on the island the next day, saying that he had never seen so many birds in one place and that his estimate was that there may have been a million tree swallows there. I don’t expect ever to witness anything like that again but will be enormously grateful to the fates if I do. In any case, to see this staging any year is something that should mark the calendar.”