When my daughter was young, her favorite color was purple. Everything was purple – her winter coat, her PJs, hair bands, you name it. Needless to say, I got pretty weary of purple.
However, there is a purple that I find endlessly fascinating – the purple martin (Progne subis). These avian aerialists are a gorgeous iridescent purple and they have already been sighted in Ohio. Martins winter primarily in South America. Their breeding territory range in North America extends from Florida to Canada.
My father and mother have always been avid bird-watchers. Whenever we are together, the conversation usually comes around to the latest bird they have seen at their home or the family cabin. Growing up, I remember when Dad brought home a large three-tiered bird house and placed it on top of the lamp pole in front of the horse barn. The next spring we had our first of many years of purple martins to reside at their new home. They were magnificent and my dad was delighted, to say the least.
Purple martins have been managed by humans for thousands of years. Native American tribes provided hollowed-out gourds to attract martins and the practice was later adopted by early settlers. Today it is estimated that more than one million North Americans provide homes for purple martins. These birds are syanthropic, meaning they take readily to man-made structures and prefer to nest near humans. Purple martins in eastern North America now nest almost exclusively in birdhouses and putting up a martin house is like creating your own purple martin neighborhood.
Purple martins are the largest of the swallow family, slightly smaller than the American robin, weighing in at just under two ounces, and with a wing span of 16 to 17 inches. The really amazing thing about these birds is they are aerial insectivores, meaning they consume insects during flight (unlike my brother who can’t even walk and chew gum at the same time!).
They dine on beetles, flies, dragonflies, moths, butterflies, wasps and other flying insects. Because they feed at altitudes higher than other swallows, mosquitoes do not make up a large part of their diet. As with many bird species, martin females and immatures are duller in color, with gray on the head and chest, and a lighter color lower belly.
Purple martin habitat consists of large, open areas with water bodies nearby. Martins are colony nesters, meaning they like to nest in groups, so the Purple Martin Conservation Association recommends that, when creating bird houses, at least four cavities be made available and that between six to 12 cavities is a great start for a colony. Martin houses can be of untreated wood, plastic, aluminum, real gourds or artificial gourds placed on a pole 12 to 18 feet high.
What matters most is that the housing can be easily raised and lowered vertically. This is vitally important for monitoring the nests and removing non-native competitors. European starlings and house sparrows are aggressive and can deter martins from nesting or can destroy martin eggs, kill nestlings, and injure or kill adults. These competitors can legally be evicted and nest removal is strongly recommended.
The female usually lays between three to six white eggs in a nest comprised of three layers — a base of sticks, a middle layer of grasses, and a third layer of green leaves. Incubation is usually 15 to 16 days and the young fledge in 26 to 32 days. Martins usually raise one brood a year.
Purple martins can use your help. If you are interested in discovering more about them, visit the Purple Martin Conservation Association at www.purplemartin.org or the Cornell Lab of Ornithology at www.allaboutbirds.org. If you have the habitat, you could become a martin landlord. Watching them is way better than TV, even if they are purple.
Brad Ross is communications specialist at the Delaware Soil and Water Conservation District. He can be reached at [email protected]