Words On Birds 08-02-24

 

     The annual swallow show is ramping up on Plum Island! Plentiful fruit and insects on the Parker River Refuge attracts tens of thousands of swallows in mid-August, and this birding spectacle is one worth seeing before they are gone by month’s end. Thousands of swallows are “staging” in the cattails of North Pool and feeding on the evening insects. The swallows form large, swarming clouds as they feed, and you can watch others skim insects off the surface of the pools.

 

     You can see large congregations of swallows anytime during the day all along the Refuge road, as these birds gather and move along the dunes and marsh. In addition to feeding on flying insects, swallows gather to feed on the bayberries growing on the bushes along the road and in the dunes. 

 

     The vast majority of birds are tree swallows, but it is fun to try to find other swallow species among them. 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 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. Tree swallows are aptly named because they nest in cavities in trees but they will also nest in nesting boxes.

 

     Barn swallows can be picked out among the tree swallows by their forked tail. 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 on beams in barns, garages and other structures.

 

     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 has a square tail. They build a mud nest similar to the barn swallow, but cliff swallows usually nest on open structure such as a bridge or open storage shed. Locally, they nest under the Hines Bridge in Amesbury.

 

     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 and drain pipes,

 

     The smaller bank swallow has a brown band across its light chest and it 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. Locally they have a colony on Crane Beach in Ipswich.

 

     You might also find a purple martin in the mix. These deep blue/purple iridescent birds are the largest of our local swallow species. The female and immature martins are lighter in color underneath. Purple martins nest in colonies in “condo style” martin houses or gourds, erected on the refuge and elsewhere. We saw a few martins still hanging out around the Lot 1 gourds early last week and a larger number of them were perched on the antennae south of Lot 2 the same day. 

 

     Swallows are a critical part of the food chain and help naturally control flying insect populations. On a warm summer’s evening, as mosquitoes and no-see-ums start to bite, the sight of thousands of swallows on the wing is a welcome sight indeed.

 

     If you have a chance this month, do take a SLOW drive on the Parker River Refuge on Plum Island. Be sure to drive slowly, as the swallows will often be covering the road. Take time to stop along the way to appreciate the phenomenon surrounding you, and maybe spend some time on the dike behind Hellcat in the early evening. The spectacle of thousands of swallows is sure to leave an indelible image in your memory.