Guest post by Bryan MacKay
Winter seems to have arrived early this year, with more snow, ice and cold temperatures in December than during the entire winter of 2012-13. With three full months of cold weather still ahead of us, we humans have a tendency to hunker down next to a warm fire or cocoon with a stack of blankets. Yet the natural world, and the animals who live there, have no choice but to endure.
This year has brought a rare visitor to Maryland to enjoy what for that species is a balmy winter vacation residence. Snowy owls are large, unmistakable, and appealing to humans. As their name implies, snowy owls have white plumage, although first-year birds have some dark flecks atop the head and on the body and wings. Snowies weigh about four pounds, twice as much as the common barred owl and half as much as a bald eagle. They stand about two feet high and have a four-foot wingspan. During the day, snowy owls usually perch on the ground; at night they hunt from a perch, taking small mammals and birds like ducks and pigeons. In just the first half of December 2013, snowy owls have been sighted at Assateague and Hart-Miller Islands, a Baltimore County airport, and farm fields in Harford and Frederick Counties.
Snowy owls nest on the Arctic tundra in late spring and summer. With the onset of cold weather, they migrate south, usually overwintering in the southern Canadian provinces and the northern tier of States. For years, it was thought that snowy owls who arrive in Maryland, well south of their normal wintering grounds, could not find enough food (typically lemmings) there and were on the verge of starvation. However, recent capture data indicates that most of these owls are in good shape with plenty of fat stores, although most are immature birds. Scientists now believe snowy owls arrive in Maryland during years when there is good reproduction. In essence, these are surplus birds expanding the species’ winter range southward. Invariably, however, a good reproduction year is followed by an average or poor one, so the next year snowy owls are again scarce in our area.
Count yourself lucky if you spot a snowy owl this winter. It’s imperative that you view it from a distance, with binoculars or a spotting scope. Snowy owls are very sensitive to human intrusion, and will fly away if disturbed. In winter, that uses energy and may threaten the birds’ survival.
To keep up with recent sightings, visit the http://www.mdbirding.com/ online community.
Brian MacKay is the author of A Year across Maryland: A Week-by-Week Guide to Discovering Nature in the Chesapeake Region. A senior lecturer emeritus in the Department of Biological Sciences at the University of Maryland, Baltimore County, he is also the author of Hiking, Cycling, and Canoeing in Maryland: A Family Guide and Baltimore Trails: A Guide for Hikers and Mountain Bikers, both published by Johns Hopkins.