The 2014-15 Snowy Owl Irruption
The open fields of Clearview Township, in Simcoe County, Ontario, have become a hotspot again this year for birders and photographers spotting Snowy Owls. Numerous birds can be observed perched on fenceposts and poles throughout the agricultural areas of the Township.
Snowy Owls normally live in the high arctic, but once in a while their range extends much further south in a natural phenomenon known as an irruption. One of the largest irruptions in many decades occurred in the winter of 2013-14 and another significant irruption has occurred again this winter with birds being sighted even further south and west than normal. In fact, observations have been reported as far south as the Carolinas and northern Florida.
The reason Snowy Owls move south is not fully understood, but new research is suggesting that the reason may be different than the commonly held belief. The cause that many people have heard is that the owls move south due to a scarcity of food in their normal habitat during the winter months. More recent findings suggest that, instead, the owls move south because of a plentiful supply of food (such as lemmings and voles) in the preceding breeding season in the Arctic. It appears that a plentiful food supply results in a larger production of birds as a result of a very successful nesting season. When food supplies are plentiful the normal clutch size of 3-5 eggs may jump to as many as 7 -11 eggs. The number of surviving fledglings may also correspondingly increase. As so many birds mature, they move south, and studies indicate that those birds are healthy and well-fed.
Research on the cause of irruptions continues, however it is apparent that we are in the midst of another significant irruption following a similar event just last year.
When large numbers of the birds move south, they attract a lot of attention. The opportunity to see this beautiful bird, and get that perfect picture, attracts numerous birders and photographers to country sideroads and it turns out that Clearview is one of the best locations to spot these visitors (birds and birders!) in the region.