By Molly Daly

PHILADELPHIA (CBS) – According to a preliminary count, there’s been a big increase in active bald eagle nests in Pennsylvania. The state Game Commission says it’s a sharp increase over last year’s mid-year report.

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Thirty years ago, the combined effects of persecution, pollution and pesticides had decimated the bald eagle population. In Pennsylvania, just three nesting pairs were left. That’s when the state game commission launched a seven-year reintroduction program. Since then, bald eagle numbers have steadily grown.

Now, there are at least 252 nests, and one is right here.

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“Two hundred years without bald nesting in Philly, and now we’ve had four years in a row with successful hatching of eaglets right here at John Heinz National Wildlife Refuge, the most urban national wildlife refuge in the country.”

Refuge manager Gary Stolz says that’s testament to the success of state and federal efforts, notably the Endangered Species Act, which was signed into law 40 years ago.

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