Sunday, September 10, 2006

Migration Study

Migration is a fact of life for most bird species in North America, and migration periods are much anticipated by birders. Since the beginning of detailed migration studies, much has been learned about how birds migrate. However, there are still open questions, such as what factors influence the routes and timing of migrants and how migration evolved. To that end, two government naturalists are tracking marbled godwits with radio transmitters in the west.

Farmer and Olson attach a small box with a wire that weighs half an ounce to the back of the bird and set it free. A solar panel on the tiny backpack provides power to send a signal for six hours each day to satellites. Such devices have long been used on other animals, but the recent development of super-lightweight transmitters have for the first time allowed scientists to track birds that weigh as little as a pound....

Using the satellite signals and Google Earth's online global-imaging service, the scientists tracked the bird. In a little less than a day, they found, it flew 600 miles to Saskatchewan.
This article focuses on two individuals, so it is hard to tell how many birds are being tracked. Given that this equipment is probably expensive, it may be a small number. One interesting result so far is that the migration routes of these two godwits confirm the importance of setting aside protected wetlands. Each bird made stops in multiple protected refuges as they made their way north from the banding station in Utah.