Snowy Owl
Nyctea scandiaca
In Boulder County the ratio of clumps of snow misidentified as snowy owls to snowy owls actually seen is about 10,000 to 1. Only two sightings have been reported to the Boulder County Audubon Society’s Monthly Wildlife Inventory since its inception in 1978. No snowy owls have been seen on Boulder Christmas Counts. Neither Norman Betts (1913) nor Gordon Alexander (1937) of the University of Colorado Museum included this species in their lists of Boulder County birds. In Birds of Colorado, Robert Andrews and Robert Righter found 28 statewide records from the 1960s, 27 from the 1970s, 11 from the 1980s, and none from 1985 to 1992. Most of these records came from eastern Colorado, but only one came from Boulder County. In December 1997 Gary Emerson and Greg Hayes saw a snowy owl along Highway 93 north of Rocky Flats.
Wintering snowy owls may be forced south into Colorado by prey shortages (mostly small rodents) in Canada. However, a firm relationship between snowy owl winter migration and fluctuations in prey populations has not been clearly documented.
Snowy owls nest in the tundra, north of the Arctic Circle. The female lays 3 to 13 eggs in a depression or shallow scrape on the ground. The number of eggs appears to depend on the availability of lemmings and other prey. Around the nest, adults give a variety of calls, including soft “whoos,” barks, whistles, rattles, and groans. These swift-flying owls are decidedly diurnal (there is no nighttime in their arctic breeding grounds), but they also can hunt in the dark.