CHICAGO (CBS) — Birders out yesterday for Chicago’s Christmas lakefront bird count documented a few unusual sightings.

A double-crested cormorant was spotted near Navy Pier, sitting on the ice next to a patch of open water.

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“Which is a bird that’s abundant in summer in the Chicago area, but it’s very rare in winter. Almost all of them go much further south in winter,” said Josh Engel, a research assistant at the Field Museum.

Engel has been taking part in the Christmas lakefront bird count since 1995 – when he was 13.

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He says the cormorant sighting was exciting.

“They’re fish-eaters so they need to have some open water where they can swim and dive under the water to catch fish,” he said. “Double-crested cormorants have in recent years became a little less unusual in winter, probably because we’ve had warmer winters. But we were surprised to see one yesterday, when it’s been such a cold, cold winter.”

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Engel says the birders also saw four snowy owls – three of them way out on ice in the lake – most likely, he says, where they’d been hunting ducks.