Snowy owl numbers down this year
For whatever reason, snowy owls (Bubo scandiacus) seem a little scarce this winter. I know of only one seen in either Cass or Clay counties just before the new year and it hasn't been relocated. Not that our little corner of the northern prairie is a magnet for these giant owls, but we usually have a few more. There have been some winters in the recent past where a short trip down any direction on the Interstate highway would produce one or two sitting along fence posts.
Just what makes these magnificent predators appear common some winters yet scarce to absent in others is a mystery. The common operating theory points to food, or lack thereof. A crash in the highly cyclic life cycle of lemmings on the birds' breeding grounds, as the thought goes, forces the owls to abandon traditional areas and head south in search of suitable feeding areas (an adult bird can consume an estimated 1,600 lemmings in a single year). It seems logical and is probably part of the truth, along with weather and other related factors.
Only its yellow eyes betray the all-white adult male of this species. Females and immature birds sport varying degrees of dark barring or spotting but always on a backdrop of white. Their feet are completely feathered, an adaptation thought to be a "mitten" of sorts to help keep Arctic cold at bay.
Snowys nest in the very far north starting at the tree line and continuing well into the tundra. They are circumpolar, meaning Arctic areas of Asia and northern Europe support snowy owl populations as well. In fact, this bird was known long before the first explorers set foot on our continent. The species name, scandiacus, refers to Scandinavia. It was the famous Swedish naturalist, Carl Linnaeus, who first classified this species in 1758.
Its handsome and striking appearance may have prompted Novelist J.K. Rowling to cast a snowy owl as a messenger in the popular Harry Potter series, at least the movie versions. Plus it made an obvious impression on earlier peoples as evidenced by the appearance of snowy owls in ancient cave paintings in Europe.
Snowy owls are large, with wingspans approaching five feet, and weigh up to six pounds. This makes them the largest owl in North America, not by apparent size but by mass. With a body fit for hefty work, this owl can and will prey upon relatively large mammals, such as jackrabbits.
Every so often I hear a story about someone in town with a snowy owl sitting in their backyard tree. While I hesitate to use the word 'never,' these sightings are almost certainly not snowy owls. Snowys are exclusively open country birds, where they can be seen sitting for hours on a perch (such as a fence post) or even on the ground waiting for prey. It is extremely rare to find one sitting in a tree.
Instead, I think there are two possible explanations for the apparent misidentifications. First, there is an Arctic population of the much more common great horned owl that is sometimes present in our area during the winter months. These birds can appear to be very pale to near-white in color and commonly perch in trees. Then there is the issue of artificial light. If a yard light (or even car headlights) shines on a bird in the dark, the creature in question is "washed out" and can appear white.
So it's out in the open where you will find them. And, to the delight of animal observers, they are diurnal, meaning active during the daylight hours. Scan long reaches of snow-covered terrain for lumps, especially those looking like dirty snow. Eventually a snowy owl will be found. Although this winter it may be tough.