Purple Martins before Martin Houses

“I wonder where purple martins nested before we put up birdhouses?”

That question came up in a conversation recently. I speculated that they probably were not very abundant historically and nested in tree cavities, but I did not know. So I did a little checking on this question.

As you may suspect because they readily occupy nest boxes, purple martins are cavity nesters. They would have nested in holes in trees.

I checked some range maps, and their breeding range is in the United States east of a line from central North Dakota south to Texas. There are some other areas, however, such as a narrow band from Manitoba to Alberta, and a few other spots along the west coast and southwest, including parts of Mexico.

I also checked Bob Stewart’s Breeding Birds of North Dakota published in 1975. He notes that purple martins were found in wooded areas of the state, and cites reports of colonies in the Turtle Mountains, around Stump Lake and Devils Lake, and Lake Washington in Eddy County during the late 1800’s and early 1900’s. He also notes that purple martins were reportedly nesting in crevices of buildings and even bridges in Grafton, Wahpeton, Oakes, Devils Lake, and Drayton.

Now, of course, their range is largely influenced by the placement of birdhouses. In the eastern United States it is almost entirely the case. However purple martins still use cavities in the western portions of their range. Perhaps the largest natural nesting colony remaining in the United States is in the mountains near Bakersfield, California where around 200 breeding pairs nest in woodpecker cavities in large valley oaks.

Whether it is birdhouses or natural cavities, Starlings and house sparrows often out compete purple martins for nesting sites in birdhouse as well as natural cavities. That is particularly true for poorly maintained martin houses. As a result, some populations of purple martins are declining, although the species is certainly not endangered or threatened.

If you are interested in more information on purple martins you might want to check the website of the Purple Martin Conservation Association (PMCA). The website contains a wealth of information about purple martins including proper placement and maintenance of martin houses. You can find it at purplemartin.org.

Chuck Lura

Natural North Dakota is supported by NDSU Central Grasslands Research Extension Center and Minot State University-Bottineau, and by the members of Prairie Public. Thanks to Sunny 101.9 in Bottineau for their recording services.