Native Species Profile - Snowy Owl (Bubo scandiacus)

Most people don't understand birders.  The idea of going birding (looking for and recording bird sightings) is seen as odd a lot of people.  Why would you go looking for birds - birds are just there.  They're around us every day - they are so common that they fade into the background and become part of the scenery.

Despite my other nature obsessions, I will admit that I don't bird (the verb).  It takes a lot of bird (the noun) to get me excited enough to go bird (the verb).  One of he few species that excites the general public (and me) enough to go birding is the Snowy Owl (Bubo scandiacus).  A Snowy Owl is not so much a bird (the noun) as it is an event.

Snowy Owl - Isabella County, MI (December 2014)

The winter of 2017 - 2018 looks to be a big year for fans of the Snowy Owl.  There have already been dozens of sighting of Snowy Owls in Michigan and birds have been reported as far south as Missouri and Virginia.  Some years the population of Snowy Owls moves southward in large numbers during the winter months.  This movement is known as an irruption - the last big irruption was in 2013 and 2017-18 looks like it will be even bigger.

The exact cause of irruptions is not well known.  It may be tied to downswing in the population of Arctic lemmings, the owls major food source.  When lemming populations fall, birds must come south to find enough food.  it may also be related to upswings in lemming population - more lemmings available during the breeding season means more young birds survive to adulthood. When there are more owls in the Arctic some of them must come south to find enough food.  I tend to believe this latter explanation because a large percentage of the irrupting Snowy Owls tend to be immature birds.

One of the reason Snowy Owls are so exciting is that they are large birds.  They measure 20 to 28 inches long and have wingspans of 49 to 57 inches.  As is typical of raptors, females are usually larger than males.  The Snowy Owl is the heaviest owl species in North America weighing 3.5 to 6.5 pounds; the Great Horned Owl, Mid-Michigan's largest resident owl weighs an average of 2.0 to 5.5 pounds.

Snowy Owls are primarily white.  Females and immature birds will have dark brown or black barring on the wings, back, and chest.  Mature males are pure white or nearly so.  Both male and female birds have bright yellow eyes

Another reason that Snowy Owls are so exciting is the fact that they are diurnal.  This means that they are active during the daytime.  Combined with the fact that they prefer open areas such as fields to wooded areas and they become easy to find.  (I say easy to find, but in January of this year it took us three trips to find one of several that had been reported nearby for weeks.)  Snowy Owls often rest on the ground - their native tundra has few trees and the birds are used to perching on the ground.  Birds that are part of the irruption often perch on utility poles so they can better see their surrounding.

Snowy Owl - Gratiot County, MI (January 2017)

Basic Information

Snowy Owl
Bubo scandiacus

Habitat:  Arctic tundra; birds may overwinter in the Continental United States, over-wintering birds usually found in open areas such as fields, prairies, airports, golf courses

Size:  20 - 28 inches long with a 49 - 57 inch wingspan, females are typically larger than males

Diet:  small mammals, birds