ROCK ISLAND, Ill. (CBS) — When you think of birds flying south in winter, you probably don’t think they’re headed to Chicago, but if you’ve spotted any bald eagles in Illinois lately, you know different.

WBBM Newsradio’s John Cody reports, as cold as it has been in Illinois, it’s been colder up north in Wisconsin and Minnesota, so the nation’s symbol has come here to Illinois and Iowa, looking for food.

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“A couple years back, when we had a real warm winter, we’d be lucky if we saw three or four here at the Lock and Dam 15 in Rock Island,” said Army Corps of Engineers park ranger Mike McKean, who works at the Mississippi River Visitor Center in Rock Island.

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McKean said frozen food sources to the north have driven bald eagles further south.

“I’m looking out the window right now. I can see about 10 or 12 just flying around off in the distance,” he said.

The numbers on Missriver.org tell the story. In five weekly counts last January at the dam in Rock Island, officials observed a total of 38 adult bald eagles and 12 juveniles. This January, they counted 314 adults and 295 juveniles.

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At Lock and Dam 18 in Burlington, Iowa, officials observed a total of 1,215 adult bald eagles and 439 juveniles last January, compared to 3,616 adults and 1,243 juveniles this Januray.