Today an invader landed in Edmonds. Well, it’s a Snowy Owl, typically a denizen of Arctic latitudes. But every few years, for reasons that are not necessarily well understood, some Snowy Owls winter in the Lower 48. They are often female or immature birds. Scientists refer to these as irruption years. Many others refer to them as invasion years.

Today’s Snowy Owl has been on a roof across the street from the playfield at 6th & Pine. It may be there tomorrow or it may move on. The barring on the head and body, seen in LeRoy’s first photo, suggests that this is either an adult female or a first year male. The bird was perched on the back side of the roof so that only its upper body and head were visible from the street. LeRoy’s second photo is of an owl that was on the Edmonds marina breakwater, November 27, 2012.

The Snowy Owl is not an owl of the forests. Its preferred habitat includes prairies, fields, marshes, beaches, and dunes. When this owl comes south, rooftops are included in its habitat preferences. A sighting is always a cause for human excitement and crow commotion. Humans want photos and good views. Crows just want it to go away. They will mob it and do dive attacks to try to chase it away, as they were doing with today’s owl.

Almost every year in winter, one or more Snowy Owls will be found on the Waterville Plateau of Central Washington, in the vicinity of the small town of Mansfield. The outlying fields will be covered in snow. The owls perch on dark rock outcroppings in the fields. They are visible because their overall whitish plumage contrasts with the darker rocks. In an irruption year, when this species comes to Western Washington, birds can be seen on Damon Point (beaches, dunes) at Ocean Shores, areas near Stanwood (prairies, fields, beaches) in north Snohomish County, and at the Samish Flats (prairies, fields) in Skagit County. Some scatter to rooftops in towns such as Edmonds and Kingston.

Science writer and photographer Wayne Lynch, author of “Owls of the United States and Canada,” explains that Snowy Owl irruptions have the longest documentation of northern owl irruptions. The first was recorded in the winter of 1833-34. Between that year and 1945, some 24 irruptions were noted, at an interval of three to five years. The irruptions seem to continue on that cycle to this day. The largest of the early irruptions was in the winter of 1926-27 when 2,363 owls were documented across the eastern U.S. Unfortunately, about 1,500 owls were taken to taxidermists in Ontario and Quebec that winter. That means a minimum of nearly 4,000 owls ventured south that winter.

In the last two weeks there have been three known Snowy Owl sightings in Western Washington. The Edmonds bird is the third. The first was at Ocean Shores and the second was on Whidbey Island. Further sightings over the next several weeks will indicate whether the winter of 2014-15 will be another irruption period for the western breeding population of the Snowy Owl.

The diet of the Snowy Owl includes rodents such as lemmings, birds, and other mammals. There is some thought that when the Arctic lemming population crashes, as it cyclically does, surplus owls head south in search of other food sources. The owl will eat rabbits, voles, and ground squirrels. In coastal areas it will feed on ducks, geese, grebes, murrelets, and sometimes song birds. The Snowy Owl watches for prey from a perch and then pursues it in flight, catching the prey in its talons. It will also search for prey by flying low or hovering and watching the ground. Noted bird author and artist David Sibley describes the healthy Snowy Owl as a nocturnal predator. He adds that when it comes so far south in search of food, it is stressed and alters its behavior to hunt during the day.

The barking alarm call of the male Snowy can be heard here: https://www.xeno-canto.org/25288.

— By Carol Riddell

Carol Riddell, author of our new “Bird Lore” feature, manages the bird education displays, on behalf of Pilchuck Audubon Society and Edmonds Parks & Recreation, at the Olympic Beach Visitor Station.