Words On Birds 08-15-25

 

     The swallows continue to gather on Plum Island and will reach their peak by mid-August. Along the Parker River Wildlife Refuge on Plum Island, they cover the bayberry and beach plum on the dune side of the road and sit atop the cattails and reeds on the marsh side. Their numbers will climb into the thousands and tens of thousands. 

 

     The swallows look like swarms of giant locust as they take flight to feed. They often cover the road, forcing cars to stop and proceed at a crawl as the swallows disperse. Extra caution is needed when driving on the refuge this time of year.

 

     On a mid-August day, you might find all six local swallow species among the numbers on Plum Island. The majority of the swallows here are tree swallows, probably making up 90-95 percent of the individuals. The adult tree swallows have a deep iridescent blue back and bright white front. The young tree swallows are brown on the back. These are the swallows that nest in the boxes that line the marshes in Essex county. 

 

     Tree swallows are aptly named because they nest in cavities in trees. But a lot of their natural habitat has disappeared and many tree cavities have been taken over by starlings and house sparrows. Nesting box programs have helped the tree swallow become more plentiful which, in turn, helps curb the flying insect population around the marsh areas where they breed. Adding a nesting box to your yard might attract these beneficial birds to your yard in the spring, especially if you live near a field or marsh.

 

     Barn swallows are the more easily identified of the swallow species gathering on the island. Barn swallows have a blue back, rust throat, buff underneath and a deep forked tail with specks of white. These are the swallows that build mud nests on eaves and beams in barns, garages and other structures. Their droppings can create a mess noticeable in clean kept barns on gentleman farms, but the majority of folks welcome these breeding birds by keeping a door or window open. The swallows return the favor by eating flying insects in the area.

 

     Similar in overall coloration to the barn swallow, the cliff swallow has the same deep blue back, rust throat and light underneath. But it has a buffy patch on the rump and a square tail. They build a mud nest similar to the barn swallow, but cliff swallows usually nest in colonies on cliffs or under an open structure such as a bridge or storage shed. It is probably the least common of the five species, but local colonies can still be found breeding under Derek S. Hines bridge over the Merrimack River, and under other local bridges around the area.

 

     The bank swallow and rough-winged swallows are the two brown-backed swallows, the latter being the larger of the two. In addition to its noticeably larger size, the rough-winged swallow has light under parts and a dusky throat. It nests individually in cavities or crevices in culverts, old drain pipes, etcetera but seldom in tree cavities like tree swallows. A pair has bred under Pike’s Bridge in West Newbury in years past and in drain pipes of bridges around the area.

 

     The bank swallow is a cavity nester like the tree swallow however, as its name indicates, it nests in colonies in burrows on the side of a dirt embankment or sand dune. They nest on Crane Beach every year. The smallest of our swallows, these brown-backed swallows have a brown stripe across their pale chest.

 

     Purple martins nest on Plum Island and in other nearby colonies and can be seen with the other swallows staging on the refuge. These deep blue/purple iridescent birds are easier to recognize as they are the largest of our local swallow species. The female and immature martins are lighter in color underneath. Purple martins nest in colonies in the gourds erected on the refuge, and elsewhere in gourds or condo-style houses. They are social birds that nest near people.

 

     All the swallows eat flying insects on the wing which make them very beneficial. They are a critical part of the food chain that can help naturally control flying insect populations. So on a warm summer’s evening, as mosquitoes start to bite, the sight of thousands of swallows on the wing is a very welcome sight indeed.

 

     If you would like help in identifying swallows, or just want to experience the awesome swallow show on Plum Island, the Friends of Parker River NWR invite you to join leaders Bill Gette and David Williams on “an evening with the swallows and egrets.”  Enjoy the annual phenomenon of countless swallows and egrets as they make their way to roosts for the night on Tuesday, August 26, 5:30pm until dark, at the Hellcat Observation Area Tower at Lot 4 on the Refuge. This is a free program, registration is not needed – just drop by!