Purple Martin: Bird Finder for April 24
Martin gourds at the Milford Point Coastal Center. Connecticut Audubon Society photo by Frank Gallo.
Purple Martin
Progne subis
Purple Martins are the largest member of the swallow family nesting in the U.S. They are nearly European Starling-sized, but thinner, with long tapered wings and a forked tail. The males are completely iridescent blackish-purple, and the females are blackish-purple above, with a dark head, neck, and chest, and pale grayish-white bellies.
In the southwest, Purple Martins can be found nesting in holes in Saguaro cactus, but throughout most of the country they are completely dependent on human-made structures, either boxes or gourds, for their survival.
Where to find it: Purple Martins inhabit open areas rich in aerial insect life. In Connecticut, they tend to be found along the coast near salt marshes, but there are a few inland colonies, usually on farmland near a large body of water.
Good places to look include our Coastal Center at Milford Point, which has a large vibrant colony at the northeast edge of the parking lot (it produces more than 100 young each year), and Hammonasset Beach State Park, in Madison, which has several active colonies – one near the nature center, and another near the swan pond. There are colonies at Sherwood Island State Park in Westport, and Cove Island Park, in Stamford. Many other colonies are scattered along the coast.
Purple Martins usually arrive in Connecticut toward the end of the first week in April. Small numbers of male scouts are the first to scope-out traditional and new nesting colonies, and they are joined later in the month by the majority of colony members.
Martins remain through August with a few lingering into the third week in September. Nesting colonies are often quite active early and late in the day.
What if the bird isn’t there? If you arrive at a nesting colony mid-day, especially on a warm sunny afternoon, there may be little or no activity around the nest gourds or boxes. Some birds may be out of sight tending eggs, but the majority will be out hunting.
Purple Martins feed on aerial insects; these insects are often caught in the rising thermal air currents which can carry them miles above the ground. The martins follow their food, and may feed so high that they can’t be seen against the blue sky. Revisit the site early or late in the day when there is more activity around the nests.
Conservation Status: Purple Martins have declined in many areas nationwide, including Connecticut and New England. According to the Connecticut Department of Energy and Environmental Protection, competition with invasive House Sparrows and Starlings for nesting space, and pesticides poisoning their food supply, are contributors to their decline. They are considered a Threatened Species in Connecticut.
The DEEP now monitors martin colonies statewide, with Connecticut Audubon Society assisting with monitoring colonies on our properties. Establishing a nesting colony in appropriate habitat is probably the best way to aid these wonderful aerial insect eaters. The Coastal Center has added several new gourd trees through grants from Connecticut Ornithological Association, the New Haven Bird Club, and contributions from Phil Donahue. We will continue to do so as funding becomes available.
More information on starting a colony can be obtained from the Purple Martin Conservation Association.
This week’s Bird Finder was written by Frank Gallo, Connecticut Audubon Society’s associate director of the Coastal Center at Milford Point. As always, it was edited by Tom Andersen.
Photos by Connecticut Audubon Society (top), and Dick Daniels and Henry McLin, Carolinabirds.org.
