Twenty-six volunteers tallied 68 species of birds across parts of Adams and Weld counties on January 2 for the Barr Lake Christmas Bird Count. The numbers of species and individual birds (18,562) were lower than past winters, but by day’s end the topic of conversation wasn’t the numbers.
Snowy Owl at Barr Lake by Gregg Goodrich
I was at our base at RMBO’s Environmental Learning Center mid-afternoon when count volunteer Peter Plage called and asked in a characteristically understated way if I wanted to come see something. He waited for my next question.
“What are you looking at?”
“Snowy Owl.”
“I’ll be right there!”
There had been a few reports of Snowy Owls in Colorado this December, part of an irruption of these spectacular birds across the upper and middle tier of states. Most winters, these predators range only slightly south of their arctic breeding grounds. Their populations are tied to the population cycles of lemmings, their primary prey during the summer breeding months. Classic theory suggested that the owls irrupt southward when the lemming populations crash on a roughly four-year cycle.
Recent research suggests irruptions may actually follow lemming population explosions. When lemmings are abundant, the owls fledge above average numbers of young. Young owls in particular are then forced to range farther to find winter food. Read more about Snowy Owls.
When I reached Pete, he was still looking at the owl about a quarter mile away in a snow-covered field where he had been scanning for Horned Larks when he spotted the owl. With 60x magnification through a spotting scope, the owl showed dark scalloping on the white wings, but the breast appeared white, suggesting an adult bird. When Gregg Goodrich, Elena Klaver and Wendy Sydow arrived a bit later, Gregg suggested cranking down the power to reduce heat shimmer. Dark scalloping then showed on the breast as well as wings suggesting this might indeed be a young bird.
The Snowy gave observers a fine show and also helped add two other species to the “count week” list. On Tuesday, after Gary Matthews and Scott Rashid found the owl along with a second Snowy a short distance away, they also found three Long-eared Owls at Barr Lake State Park that had been missed on the count day. The following day, John Drummond found the Snowy and added Lapland Longspur to the count week list. Birders continued to spot at least one Snowy through Thursday.
~ Chuck Hundertmark, Compiler, Barr Lake Christmas Bird Count
