The purple martin is the largest member of the swallow family in North America. Adult males are glossy, purplish blue overall, and may appear black in low light. Females and young males are light gray below. Purple martins sing and are often on the wing a few hours before dawn. The song is a gurgling guttural warble. The call is a two-note “tchew-tchew” or “chur-chur.”
Length: 8 inches (tip of bill to tip of tail).
Habitat and Conservation
Purple martins are not well adapted to cold, rainy weather, and regional die-offs may happen if these conditions persist for an extended time. Competition with introduced European starlings and house sparrows, which aggressively evict and sometimes kill young and adult martins, may also contribute to their population declines in some areas. Though originally cavity-nesters, martins now rely almost entirely on nest boxes humans provide for them.
These aerial acrobats catch flying insects on the wing. They are not major predators of mosquitoes, which fly much lower than martins do. A martin colony, however, may catch and eat several hundred beetles, horseflies, grasshoppers, dragonflies, and wasps each day.
Common summer resident in appropriate habitat, where nesting sites are available. Populations are declining over much of North America.
Martins begin arriving in Missouri in early March. There is usually only one brood a year. This gregarious species forms large flocks beginning in July. In August, martins gather in large flocks prior to fall migration. A nighttime roost in Springfield once contained over 30,000 birds. Such flocks join together as they migrate southward. In a few weeks they are on their winter range in southern Brazil. Millions of them roost in city parks in the state of Sao Paulo from November through January.
Generations of Americans have greeted the annual return of these enchanting birds, with their cheerful calls, graceful flight, and faithful reappearance at a setup of martin boxes or gourd homes.
These endearing birds have a long history with humans on our continent. Native Americans provided gourd nests for them.
You can help martins survive by erecting and maintaining next boxes or gourds on your property. Plans and instructions are available from the Missouri Department of Conservation.
These acrobatic swallows hunt winged insects, helping to check the populations of those insects.
As migratory birds, purple martins play a role in all the regions of the world the live in and fly through.