O. S. Pettingill/CLO

Purple Martins (Progne subis) are one of the most beloved and studied swallow species in North America. For centuries, their social antics have captivated the humans who provided housing for these glossy bluish-black cavity nesters. Purple Martins have taken to artificial structures so readily that in eastern North America the species almost always nests in birdhouses and gourds.

According to the Breeding Bird Survey, martin populations have not changed overall across North America since 1966, but the Purple Martin is one of The Birdhouse Network's Most Wanted because of significant declines in some regions. For example, populations have declined by more than 50 percent in Florida and in a belt across the upper Midwest (see map). Declines may be caused in part by a decrease in natural cavities and suitable habitat and increased nest-site competition with nonnative European Starlings and House Sparrows.

Purple Martins are long-distance migrants. They winter from Venezuela to Brazil and breed along the West Coast, the eastern and central portions of the United States, and parts of Canada and Mexico. Their nesting preferences vary regionally. In eastern North America they breed almost exclusively in manmade martin houses. In the West, they nest in natural cavities and woodpecker holes, as well as in artificial structures in some areas. In Arizona, New Mexico, and the mountainous West, they still have not taken to nest boxes.

Purple Martin population trends, 1966-1996, based on the U.S. Breeding Bird Survey. Populations have not changed overall across North America since 1966, but significant declines are occurring in some regions, such as in Florida and in a belt across the upper Midwest.

More than one million nest-box monitors are estimated to maintain Purple Martin houses in North America. Unfortunately, the vast majority have little success in attracting these insect-eating aerialists even in suitable habitat. Because martins nest in groups and return to the same site each year, establishing a new colony is more complex than providing a typical songbird box. See the sidebar for tips and visit the Purple Martin Conservation Association at <www.purplemartin.org>.

You can aid in conservation efforts by providing housing for these birds in areas where they readily colonize boxes and gourds, especially where declines have been observed. You can provide valuable information on Purple Martin nesting biology by submitting your data to The Birdhouse Network.

Return