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New information on Purple Martin migration!

The latest news on Purple Martin migration is officially out, and it is stunning. York University scientist Bridget Stutchbury, her staff, and PMCA staff have tracked two female martins from PMCA’s research colony at Edinboro, PA to Brazil and back. In June, 2007 the birds were fitted with special tracking devices called geo-locators that record daily light levels. Knowing time of local sunrise and sunset on a given date allows one to approximate a position on the globe. The birds were recaptured in May, 2008, and the geo-locators were removed. A plot of the downloaded data revealed their migration routes, times, and wintering areas.

The results of this research are significant, not just for Purple Martins, but for science and ornithology as well, because no one has applied this technology to small birds before. Thus, we kept the news quiet so that the scientific results and technical details could be published first in a research journal. We are proud to report that the prestigious journal Science published an article on February 13th. You can read the abstract and supplemental information at and and The National Geographic Society funded part of the study, and they, too, have published a piece that you can read at . Scores of newspapers (e.g., are running various versions of the story that also includes new information on the migration of the Wood Thrush. PMCA members* will get the full, inside story in the April issue of the Purple Martin Update.

Photo by Bridget Stutchbury.

Geolocators don't transmit signals, they collect data on light levels.

Martin with Geolocator
Photo by Timothy J. Morton.
An adult male Purple Martin at the PMCA's Edinboro, PA research colony returns to feeding it's young soon after being fitted with a geolocator.

* Not a PMCA member? Join online.or call 814-833-7656. Already a member; why not renew now? Your membership helps the PMCA maintain its research programs.


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