WILLMAR — The flight from Willmar to the Amazon River basin in Brazil covers more than 4,000 miles.
Dozens of purple martins in a colony maintained by Dick Doll of Willmar make it every year. We will soon be learning a lot more about how they do it, and how they return.
Doll has been working with researchers on projects to monitor purple martins ever since 2007, when he began banding birds in his colony north of Willmar. Two years ago, the research took a new step when tiny, geo-locators were glued to some of the birds.
None of the geo-locators made the trip back the next year, but this year one has. Doll has sent the tiny electronic chip for an analysis that will reveal loads of information about the bird’s route and wintering grounds in Brazil.
He knows this already. His bird is tied with a geo-tagged bird from a Brainerd colony for going the farthest into Brazil.
Doll’s role in the on-going research is part of an article published recently in the Loon, a magazine of the Minnesota Ornithologists’ Union.
Learning all that we can about purple martins is important to their survival. The population of purple martins has declined by about 70 percent since 1966, according to the article.
The birds rely on human-made structures in North America for nesting, and we can keep a pretty close eye on them here. Doppler radar has helped researchers locate their four primary roosting sites in Minnesota, but it is hard work by dedicated people like Doll that provides some of the most important information. His diligent work at the Willmar roosting site has shown that birds from a number of nesting colonies in Minnesota mingle here.
We know very little about the bird’s wintering grounds in Brazil. The geo-locator information now being analyzed should greatly help researchers.
It takes time before the returned geo-locator’s data can be analyzed, and Doll is eager to learn what the chip from his bird will reveal. The birds typically make the fall trip to the Amazon in less than two weeks. They will make a few stops in states and in Central American countries, but also make a very long hop over open waters in the Gulf of Mexico.