Surprise, surprise! No, not in Costa Rica, but this bird was still a big surprise in Denver, Colorado. where I spent the holiday period.

Immature Snowy Owl (Nyctea scandiaca) at Standley Lake, Jefferson County, Colorado; photo by kind courtesy of  AJ Deets

This Snowy Owl is a very large owl, measuring slightly larger than the Great Horned Owl (Bubo virginianus), a species sometimes found in Costa Rica. It is common only in the far north, leaving Arctic breeding grounds to winter in Canada and northernmost United States. In some years, however, numbers of mostly immature individuals fly further south. This individual in Jefferson County, Colorado, was a huge attraction to birders and photographers beginning in late December 2017. The considerable dark spotting means that this is probably an immature bird; spotting is lighter on females and practically absent on adult males.

This bird sat up nicely in a blue-sky mid-afternoon on a short post on the wall of the dam of Standley Lake. Daughter Mariana and I found the bird largely thanks to local birders AJ and Heidi Deets who had located it with a spotting scope, through which they took the photo above. This owl, by now locally famous, permitted a fairly close approach by numerous birders and photographers. This capped a fine outing that had included a distant view of an adult Golden Eagle (Aquila chrysaetos).

Friend Larry Waddell lives part of the year here in nearby Aquiares but spends some of the winter months in Minnesota, where he took the following photographs of an immature Snowy Owl:

Note how much darker is the plumage of this Snowy Owl, caught in flight by Larry Warddell

Here’s the same bird at rest:

Snowy Owl at Grand Marais, Minnesota, courtesy of Larry Waddell