This is Bird Note.

Biologist Eric Green has been taking blood samples from

Osprey chicks in Northwest Montana for years.

We come with a bucket truck when her babies are, you know,

the size of a small cat and we do an alien abduction.

We grab the chicks, bring them down to the ground and take a very small blood

sample. The Ospreys live near the toxic

aftermath of decades of copper mining. Ospreys eat fish and over time

pollutants found in the water become concentrated in their bodies,

which means their blood offers a window into how pollution moves through

the food chain. Green found surprisingly high levels of

mercury in the Osprey chicks. The upper limit in human blood is set

about five parts per billion. And these chicks right here have

routinely 250, 300, 350 parts per billion.

If you or I walked into St. Pat's right across the river here,

with those levels of mercury, it would be considered like code blue.

I mean, the doctors would be freaking out and

starting chelation therapy in the whole works.

In short, bad news for the chicks, but the information helped Green

determine the mercury wasn't coming from the copper mines,

but instead from abandoned gold and silver mines elsewhere.

The baby Ospreys taught researchers that pollution might lie in places they

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