Bird enthusiasts this year report elevated levels of these iconic birds from the Arctic flying into the lower 48 states this winter in a mass southern migration that leading owl researcher Denver Holt, head of the Owl Research Institute in Montana called “unbelievable. What we’re seeing now it’s unbelievable,” he said.
A small of the iconic owls fly south from their Arctic breeding grounds each winter but rarely do such vast quantities venture so far away even amid large-scale, periodic southern migrations known as irruptions.
From the Owl Research Institute:
Holt, who has studied snowy owls in their Arctic tundra ecosystem for two decades stated: “This is the most significant wildlife event in decades.”
Begun in 1992 in Barrow, Alaska, the Snowy Owl project is focused on the owl’s diet, habitat, and reproductive success. Thanks to the United Iñupiat Corporation and Barrow Environmental Observatory for permitting access to field sites.
Through our research, we have discovered that Snowy Owl nesting fluctuates with the population cycles of the Brown Lemming.
In tracking studies, in conjunction with the Raptor Center of Boise, Idaho, we found that Snowy Owls engage in east to west, high-latitude movements from Barrow to Russia, then from Barrow to Canada. These migrations underscore the fact that conservation of this species will require large-scale, international efforts to protect Arctic habitat.
Occasionally, Snowy Owl populations irrupt into more southern latitudes. In 2005-2006, we had first-hand experience of this phenomenon when a population of Snowy Owls overwintered in western Montana. During the event, we collected dietary data and determined that the owls were primarily eating voles (95%).
The irruption emphasizes the fact that Snowy Owls require large areas of open lands, beyond the Arctic, to accommodate their nomadic tendencies.
Holt and other owl experts say the phenomenon is more than likely linked to their food supply of lemmings, which is a rodent that accounts for roughly 90 percent of their diet during breeding months that stretch from May into September. The largely nocturnal birds also prey on a host of other animals, from voles to geese.
An especially plentiful supply of lemmings last season likely led to a population boom among owls that resulted in each breeding pair hatching as many as seven offspring. In comparison, a typical clutch size of no more than two is the norm, Holt said.
This year greater competition for food in the Far North by the booming bird population may have driven the mostly younger, male owls much farther south than in a normal year.
Current research on the animals is very scarce because of the remoteness and extreme conditions of the terrain the owls occupy, including northern Russia and Scandinavia.The surge in snowy owl sightings has brought bird watchers and Owl enthusiasts flocking in from Texas, Arizona and Utah to the Northern Rockies and Pacific Northwest, pumping lots of tourist money into local economies and crowding parks and wildlife areas. The mass migration has triggered widespread public fascination that appears to span both age and interest.
According to Frances Tanaka, a volunteer for the Nisqually National Wildlife Refuge northeast of Olympia, Washington; “For the last couple months, every other visitor asks if we’ve seen a snowy owl today.”There have also been reports that are not so pleasant, such as skinny, underfed owls being seen at some sites, including a starving bird that dropped dead in a farmer’s field in Wisconsin, which may suggest that this migration may have a much darker side than just a novelty. Holt also said that one landed at an airport in Hawaii in November and was shot and killed to avoid collisions with planes. He also stated that the snowy owl populations are thought to be in an overall decline, possibly due to climate change which has lessened the abundance of vegetation like grasses that their main food supply, the lemmings rely on.
This winter’s snowy owl irruption, with multiple sightings as far south as Oklahoma, remains largely a mystery of nature.
Holt said in a statement regarding the Snowy Owls migration further south: “There’s a lot of speculation. As far as hard evidence, we really don’t know.”