In a once-in-every-five-year-or-so event, snowy owls of the Arctic have been winging into the Lower 48 and turning heads.  The nearly two-foot-tall, predominantly white owls —Harry Potter’s Hedwig was a snowy — are hard to miss.  Most snowy owls normally live year-round in the Arctic National Wildlife Refuge and other sites north of Alaska’s Brooks Range; a few overwinter in the Northern Plains and New England.  But last fall they were spreading across the U.S in great numbers.

Sharp-eyed folks at the Oregon Coast National Wildlife Refuge Complex report sightings there.  Other sightings come from as far east Parker River National Wildlife Refuge in Massachusetts and as far south as Kansas.  Snowies also were spotted in Connecticut, New York, Maine, Vermont, Illinois, Michigan, Minnesota, Missouri, North Dakota and Washington state.

Why do snowy owls sometimes fly south en masse?  Snowy owls’ favorite prey are small rodents called lemmings, which are notorious for boom and bust population cycles.  Biologists think the owls’ “irruptions” south from the Arctic occur when lemmings are in short supply.  Sightings of snowy owlers in the Lower 48 ere compiled on a  map from reports on eBird and state bird listservs.

Unlike many other owls, snowies are active in the daytime.  They tend to perch at high points overlooking open sites such as beaches and airports.  Exhausted from their long flights, some starve if prey is scarce.

The Cornell Lab of Ornithology has more information on snowy owls.

Photo: Pat Gaines, Creative Commons