The seasonal report of the appearance of snowy owls at the start of winter attracts our full attention with all the environmental concerns regarding global warming and the effect on the scheduled annual migration of wild birds.
The population has already dwindled to around 200,000 in the northern hemisphere with only 40,000 left to migrate here at the start of winter. Since the year 2013, there has not been a huge influx of snowy visitors with early speculation that this was then due to a shortage of their favorite food, the lemming. A snowy owl lives on about five lemmings in a day, or more than 1,600 in a single year as a diurnal hunter day and night.
However, to refute this observation, ornithologists visiting the Arctic found that owl nests that year were overflowing with leftover food from dead lemmings, which later changed our opinion of the reason for the mass departure. It was not a shortage of lemmings but an abundance of young owls in such numbers that they cluttered their habitat. Subsequently, they were harassed by their parents and other owls to leave their usual territory and migrate south in record numbers. When this happens, as it did in 2013, the massive movement is, in birdwatching terminology, called a population “irruption”.
As soon as it appears, the snowy owl is immediately noticed as a high-level 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 usually larger than the male and has striped markings all over her body as opposed to the male’s almost entirely white plumage like in the illustration my daughter Elizabeth helped me draw sitting in a pine tree a few miles away my home in Fairhaven.
Their piercing yellow eyes are fixed in their heads to see only in one direction, causing them to rotate on their necks. Excellent hearing allowed them to follow audible movements when we were trying to get a closer view.
We have seen snowy owls stop frequently to roost on a coastal landscape very similar to the dreary northern tundra habitat similar to those on Cape Cod, Cranes and Salisbury beaches, Plum Island and recently from Logan Airport where one was injured in traffic but could not be rescued by conservationists. .
Females make their nests by digging a shallow depression in the ground, laying more eggs when prey is plentiful where they choose to breed. After the eggs hatch, the male for a time brings her food from a wide variety of mammals and birds, including ducks, geese, fish and carrion.
The technical designation for the species of snowy owls is Bubo scandiacus, which makes them look like fearsome creatures when defending their nests or young. They have been seen preying on predators like crows, foxes, wolves, and even swooping humans.
Conservationists now recommend giving snowy owls plenty of space because when disturbed, their movements are noticed by the chirping of crows, eagles and crowds of people. Leaving them alone on their majestic sentinel tour of the northern tundra is a birding and wildlife watching adventure worth preserving for future generations.
By George B. Emmons