Snowy Owls Aren’t Starving: Two Canadian Farmers Help Bust a Pervasive Myth

Marten Stoffel with Snowy Owl by Daniel Dupont

(Wiebe; Photo Daniel Dupont; 11 Jan 2017)

Every year Snowy Owls descend out of the Arctic, sometimes in smatterings, sometimes in mas­sive irruptions, to spend winter in south­ern Canada and the Lower 48 states. They pop up in odd places—hunkering down on haystacks in farm fields, just off the runways at airports, atop light poles in grocery store parking lots—to the de­light of birders and Harry Potter fans.

Yet some people feel sorry for the snowies, believing them to be hungry vagrants. Last January, when Snowy Owls were being sighted in Michi­gan’s Upper Peninsula (as they are every winter), a local TV station re­ported that the owls’ southern travels were “linked to food supply” and that “Snowy Owls often arrive in Michigan weakened and starving.”

It’s a popular myth that Snowy Owls are driven by starvation to fly south, and according to University of Sas­katchewan scientist Karen Wiebe, it’s generally not true. In August Wiebe and her graduate student Alexander Chang published research that showed Snowy Owls wintering in southern Canada ap­peared to be doing just fine. They found that the average body mass of a wild adult Snowy Owl was 73 percent above the emaciation threshold. Indeed, many of the owls actually put on weight over the winter by increasing their subcu­taneous fat stores (fat that accumulates under the skin on birds’ chests and beneath their wings and is used for both insula­tion and energy).

Wiebe’s findings came from detailed data on the body condition of more than 500 wild Snowy Owls trapped and banded on the prairie near Saskatoon over more than a decade. But the data set wasn’t gathered by Wiebe. She bor­rowed it from Marten Stoffel and Dan Zazelenchuk, a pair of Saskatchewan owl-banders.

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