A tropical bird rarely seen in Colorado is hanging out at Boulder County pond

A tropical water bird rarely seen in Colorado appears to be taking a summer vacation at a private Boulder County pond, to the delight of hundreds of Front Range birdwatchers.

This is only the fourth recorded sighting of an anhinga in Colorado and the first seen in more than 20 years, said Peter Gent of Colorado Field Ornithologists.

The anhinga is a long-necked and long-tailed swimmer most often seen in lakes, ponds, rivers, coasts and wetlands in Florida, Texas, the mid-Atlantic and southeast U.S., according to the National Audubon Society.

It’s about the size of a heron and is often compared to a cormorant, but it has a long, narrow, dagger-like bill, a fan-shaped tail and white markings on its upper wings.

Boulder County birders first got word of the possible anhinga sighting on June 2, and Gent said he rushed to the area of 95th Street in Boulder County to catch a glimpse.

“I was just amazed,” he said. “I’ve seen lots of birds in Boulder County and Colorado, and I wrote myself a list at the beginning of spring of all the birds that are really rare that I could possibly see in Boulder County. The anhinga was not on it.”

The last documented anhinga sighting was at Barr Lake State Park on May 3, 2003, according to the group’s Colorado Bird Records Committee. Before that, the anhinga was seen in Aurora in 1927 and along Coal Creek in what is now Broomfield County in 1931, Gent said.

There’s no definitive answer why this anhinga made the journey so far out of its normal range, Gent said. One possibility is that rare birds are brought to Colorado by big storms sweeping them northward, while another is that climate change is influencing bird behavior.

“Of the 20 species that have most recently been seen for the first time in Colorado, a large majority are species from the south,” Gent said. “In other words, as the climate is getting warmer, birds that really like hotter weather can tolerate things in Colorado better than they used to.”

An estimated 300 bird enthusiasts have stopped by to try to glimpse the female anhinga since it was first spotted, and Gent said he’s run into longtime friends from Centennial and Fort Collins who made the trip to see her.

It’s not clear how much longer the anhinga will stick around, Gent said.

“You really cannot tell with rare birds. At least twice, we saw it take off and circle around and thought, it’s out of here. But each time it’s come back, and a number of people have seen it catching fish,” he said. “At the moment, it seems relatively happy, so it could easily stick around for another week.”

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