Snowy Owl

Bubo virginianus

The Snowy Owl appears in marsh areas mostly during times of southward migration from tundra areas. With a wingspan of 55 inches and a length of 20 inches, it is a fairly large bird that feeds mostly on small mammals. Unlike many other owls, the Snowy Owl hunts mostly during the daylight hours. Male Snowy Owls can be almost pure white, while females tend to have some black barring on their backs and tails. Both species have rounded heads, small, sharp beaks, and yellow eyes.

The Snowy Owl is another tundra bird which winters cyclicly in the Chicago area (that is, they may be numerous one year, and be rare or completely absent from the area during the following several years).

The years the Snowy Owl appear in large numbers are known as "invasion years." The winter of 1996-97 was an invasion year, as were the winters of 1991-92 and 1980-81. These cyclic invasions may be tied in with population crashes of prey species (lemmings) on their "normal" wintering areas in the far north.

Snowy Owls were formerly far more frequent in the Calumet area. Eight were observed on the December 1980 Calumet City-S and Ridge Christmas Bird Count, but the bird is now seen only rarely in the Calumet region (perhaps the addition of more dumps, golf courses, etc. have made the area less attractive to the species). The bird now seems to prefer lakefront sites (especially Northerly Island) and is seen there much more frequently.