Owl Irruption

Photo - WI DNR

Keep a sharp eye out as Snowy Owls are being reported in the upper Midwest and great lakes states in what has been called unusual numbers for November and December.   Concentrations of them appear to be along the Lake Michigan coastline.      

This is a large bird (3 to 6 pounds) sporting bright white plumage, large yellow eyes and larger feathered talons.  Home territory to this bird is the treeless tundra above the Arctic Circle. And while small numbers may visit Wisconsin from time to time periodically large numbers will show-up in an event called an owl ‘irruption’.        

These owls hunt during daylight hours and will roost on almost anything. They like flat open land (it’s what they know), sometimes sitting on the ground, but more often on hay bales, fence posts, telephone posts, rock piles, muskrat houses, tree snags, silos, and other structures.  Snowy Owls will dine upon almost any live thing that moves - voles, mice, lemmings, waterfowl, rabbits, muskrats, weasels, and pigeons. Other bird species are taken as well.       

What is the cause of these irruptions?  It is hypothesized that a temporary abundance of lemmings allows the owls to successfully raise large families, and then these young owls disperse southward by the hundreds to avoid competition with older birds for winter territories.      

Because these birds are not accustomed to seeing humans they will appear fearless in your presence.  As a consequence approach them with caution and observe them at a distance.  Do not flush them.  Enjoy the rare sighting of this beautiful bird.      

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