One of the north country's emblematic species is the subject of a mercury study in northern Minnesota:
For 10 nights this month, a specialized team patrolled 13 northern Minnesota lakes in Superior National Forest. Their target? Loons.
The researchers captured, tested and released 34 of the birds. The primary goal was to measure levels of mercury in them by sampling their feathers and blood; that could help shed light on how much mercury is accumulating in the environment.
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