Snowy Owl Invasion!: Tracking an Unusual Migration
THE INVASION On a cold windy day in November 2013 wildlife biologist David Brinker trudged across Assateague Island in Maryland He was searching for saw whet owls as part of a project to study their migration travels north and south But what he found instead surprised him On one sand dune peeking through winter dried plants sat a big white bird a snowy owl Snowy owls often rest on the ground and are naturally colored to blend in
These big owls spend summers hunting and breeding in the Arctic Most remain in the Arctic year round However each winter some migrate south to have less competition for food It was unusual to see any as far south as Maryland though Yet this was the second snowy owl Brinker had seen on Assateague in the past couple of weeks Over the next week Brinker noticed that bird watchers online were reporting an unusual number of snowy owl sightings in Canada The reports from the Cape Race area at the southeastern tip of Newfoundland Canada were amazing 43 snowy owls or snowies spotted on November 23 138 on December 1 and 206 on December 8 According to Ken Knowles a birding tour leader in that area It's rare to see more than ten snowy owls in an entire winter Within this short time I saw more than I'd seen in thirty years Brinker was fascinated Clearly this year snowies were pouring south out of the Arctic he said Something big was going on So what was it Snowy owls traveled south and stayed for the winter even in Washington DC
HISTORY N THE MAKING In the Arctic snowy owls usually keep to themselves except during the breeding season
Scientists call what happened during the 2013 2014 winter an irruption That's a sudden population increase of an animal in an area where it's not usually found In an irruption migrating animals often invade areas far beyond their normal range such as Arctic snowies traveling in large numbers to parts of southern Canada and the United States What causes an irruption of snowy owls Why were there so many snowies along the Atlantic coast that winter The answer has to do with the previous summer and why there were so many snowies that year The female right is eating a lemming delivered by the male left He supplies food while she alone stays on their nest keeping the eggs warm while the chicks inside develop
