December 2010: The U.S. Geological Survey hosts a website where you can track the migration of common loons (Gavia immer)from the Upper Midwest and Northeast to the Gulf and Southeast U.S. Individual birds are tracked using satellite telemetry.
If you want to explore the website, it's at this link.
I was reminded of this site today after talking to a friend who lives on Leech Lake (Walker/Cass County, MN). When I asked if the lake had frozen over yet, she said that there were still patches of open water, and that an uncommonly large number of loons had gathered in those locations, presumably as a rest stop on their migration south from Canada. Yesterday in the Walker Bay area, where the lake is I think 200 feet deep, they saw an estimated 500-1,000 loons in the water. That mass of birds had drawn the attention of local bald eagles, about a half-dozen of which were perched on trees along the shore and were swooping down on the loons. It must have been quite a sight.
Update : I am impressed by the length of the migratory legs of some of these birds, such as this one by 55490:
That's longer than I can drive my car in a day; they must be able to sense upper-level wind directions. Now, as April arrives, the migration is reversing - trackable at the same link.
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