Global warming, “mystery of nature”, or just going where the food is?
Bird enthusiasts are reporting rising numbers of snowy owls from the Arctic winging into the lower 48 states this winter in a mass southern migration that a leading owl researcher called “unbelievable.”
Thousands of the snow-white birds, which stand 2 feet tall with 5-foot wingspans, have been spotted from coast to coast, feeding in farmlands in Idaho, roosting on rooftops in Montana, gliding over golf courses in Missouri and soaring over shorelines in Massachusetts.
A certain number of the iconic owls fly south from their Arctic breeding grounds each winter but rarely do so many venture so far away even amid large-scale, periodic southern migrations known as irruptions.
“What we’re seeing now — it’s unbelievable,” said Denver Holt, head of the Owl Research Institute in Montana.
“This is the most significant wildlife event in decades,” added Holt, who has studied snowy owls in their Arctic tundra ecosystem for two decades.
Holt and other owl experts say the phenomenon is likely linked to lemmings, a rodent that accounts for 90 percent of the diet of snowy owls 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…
He said snowy owl populations are believed to be in an overall decline, possibly because a changing climate has lessened the abundance of vegetation like grasses that lemmings rely on.
This winter’s snowy owl outbreak, with multiple sightings as far south as Oklahoma, remains largely a mystery of nature.
“There’s a lot of speculation. As far as hard evidence, we really don’t know,” Holt said.