The seasonal report of the appearance of snowy owls in early Winter gets our undivided attention with all the environmental concern about global warming and the effect on annual wild bird scheduled migration.
The population has already declined to about 200,000 in the northern hemisphere with only 40,000 left to migrate down here in early Winter. Not since the year 2013 has there been a huge influx of snowy visitors with early speculation that it was then due to a shortage of their favorite food, the lemming. A snowy owl lives on approximately five lemmings in one day, or more than 1,600 in just one year as a diurnal hunter by both day and night.
However, to refute this observation, ornithologists visiting the Arctic found that owl nests that year were overflowing with leftover, dead lemming food that then changed our opinion of the reason of massive departure. It was not a shortage of lemmings but to flourish an abundance for young owls in such large numbers they were crowding their habitat. Subsequently, they were hassled by their parents and other owls to move out of their usual territory and migrate south in record numbers. When this happens, as it did in the year 2013, the massive movement is, in bird-watching terminology, called a population “irruption.”
On appearance, the snowy owl is immediately noticed as a high-profile visitor. It is the largest on the continent with a wingspan of at least 5 feet and weighing up to 6.5 pounds. The female is typically larger than the male and has lined markings all over her body as opposed to the nearly all-white plumage of the male as in the illustration that my daughter Elizabeth helped me draw sitting in a pine tree a few miles from my house in Fairhaven.
Their piercing yellow eyes are fixed in their heads to see in only one direction, forcing them to swivel around on their necks. Excellent hearing allowed them to follow audible movement when we were trying to get a closer view.
We have seen snowy owls frequently stopping to perch on coastal landscape very similar to northern bleak tundra habitat similar to those on Cape Cod, Cranes and Salisbury beaches, Plum Island and recently Logan Airport where one was injured in traffic but could not be saved by conservationists.
The females make their nests by digging a shallow hollow in the ground, laying more eggs when prey is abundant where they choose to reproduce. After the eggs hatch, the male brings her food for a period of time from a wide variety of mammals and birds, including ducks, geese, fish and carrion.
The snowy owls’ technical species designation is Bubo scandiacus, making them seem like fearsome creatures when defending their nests or young. They have been seen going after predators like ravens, foxes, wolves and actually dive-bombing intervening human beings.
Conservationists now recommend giving snowy owls plenty of space because when disturbed, their movements become noticed by heckling crows, eagles and crowds of people. Leaving them alone in their stately sentinel statuesque visitation from the northern tundra is a bird-watching, wildlife adventure worth preserving for future generations.
By George B. Emmons
