Prepare for Purple Martin Migration
Every year millions of Purple Martin Birds (Progne Subis) migrate from South America to North America for breeding from their non-breeding nest sites in South America. The Cornell Lab of Ornithology believes it takes purple martins about four to six weeks to travel from Brazil, Colombia, Venezuela, Ecuador, Peru, Bolivia, Paraguay, Argentina, British Guyana, Suriname, and French Guiana to their preferred breeding locations in the United States and Canada. Cornell Lab scientists believe they travel North to take advantage of longer summer days in northern latitudes for protracted feeding times.
As they travel north it is important to know when to have your purple martin houses, gourds and racks set up and to open your Purple Martin bird houses. Before the arrival of the European starling , and invasive bird to North America, Native Americans would hollow out natural gourds and create bird houses for the purple martin. Today, the Purple Martin bird relies on humans for their housing needs. As the purple martin migrates north to Eastern North America they search out nesting sites. West of the Rockies they nest in trees, woodpecker holes or other natural cavities. In Eastern North America humans need to prepare purple martins houses. To prepare progne subis birds new nest sites Cornell lab recommends following the Ravenox bird migration map below which shows the estimated arrival dates of the Purple Martin bird in different areas around the country. Make sure you’ve got everything in place well in advance of arrival of the first scouts. Keep an eye out daily for their arrival. Be sure to leave entrances to the martin houses nest sites closed until you spot that first Purple Martin scout, or other species of birds could take advantage of your Purple Martin gourds and set up their own nests in your purple martin houses. Be sure set up traps for non-native species of sparrows and starlings or they could invade your Purple Martin colony before your first Purple Martins even arrive. Usually, younger Purple Martins arrive about 4 to 12 weeks after the first adults arrive.
In general, your Purple Martin gourds and birds houses can attract Purple Martins well into summer so be sure to not take down your gourd racks or bird houses until late August or early September in northerly areas. Fledgling Purple Martins look for housing sites late in the Fall for housing opportunities for the coming year!