Exploring Nature: America’s Favorite B
ird?
The one bird probably most welcome back to our area each spring is a large swallow, one of eight swallows that occur in the United States.
That bird is the purple martin, scientific name Progne Subis.
The purple martin is a neotropical migrant aerial insectivore and as the name implies, it eats insects on the wing, at heights of about 100 to 200 feet. Among the bugs it swallows on the wing are wasps, grasshoppers, beetles and dragonflies. Although it has a reputation for eating mosquitoes, in truth this pesky insect accounts for less than three percent of the martin’s diet.
While purple martins start arriving in the Rio Grande Valley as early as late January, most of these birds return to our area starting in March and running through May. They’ll stick around until fall when they will depart for South America. A whopping 90 percent will over-winter in Brazil while lesser numbers will stay in Venezuela and Bolivia.
North America’s largest swallow, the purple martin weighs about two ounces and has a 15-inch wingspan. Adult males are a glossy blueblack and females are a dull, sooty gray.
The other swallows found in the United States include cave, bank, barn, cliff, tree, Northern rough-winged and violet- green.
Native Americans hung up hollowed-out gourds to attract martins. Hollowed gourds are still used, but the most common martin house is a multi-unit house of wood or metal atop a pole.
The houses are almost always painted white since this color reflects the sun and keeps young birds from over-heating. If you’d like to see a typjerry purple martin house, visit the Patsy Glenn Refuge in the heart of downtown Wimberley — it’s located alongside the walking trail at the twoacre refuge.
One indication of just how popular this bird is can be found in one amazing fact — approximately one million people in North America provide housing for purple martins. Wow.
