For many years I have enjoyed the gurgling chatter of purple martins as they've perched on multi-roomed houses set on poles about 15 feet above ground. They've put on aerial displays high above lakes such as Minnetonka, Waconia, Leech and Bemidji, and over the Mississippi River.

Both male and female purple martins, the largest member of the swallow family, are busy feeding their young. We see them bringing in beaks filled with insects that the young snatch and swallow, often with difficulty. Most food is procured on the wing and in the usual swallow fashion of darting, swooping and wheeling in streamlined flight. The variety of insects they consume includes moths, butterflies, dragonflies, and many species of beetles, bugs and flies. Sometimes they can be seen flying close to the surfaces of lakes or rivers, dipping down for drinks.

Only one brood of young is raised each summer by martins in the Upper Midwest. The nest is started about a month before laying eggs. The eggs hatch after about 15 days of incubation, and the young remain in the nest for nearly a month. Once the young leave the nest, they often return each night for about a week.

After the nesting season ends each summer, martins gather into assembly groups before leaving the area. The early migration of martins peaks in the second half of August in Minnesota. They leave for their winter home in Brazil. Many will return to the same nesting area next spring.

Jim Gilbert taught and worked as a naturalist for 50 years.