Date: August 31, 2016
Source: Central Ornithology
Publication Office
Snowy Owls capture the
imagination, but ornithologists know surprisingly little about how these birds
of the far north fare during the harsh winters they endure. The researchers
behind a new study in The Auk: Ornithological Advance strapped and tracked
Snowy Owls wintering in Canada and found that while age and sex affect the
birds' condition, most do fairly well, showing few signs of starvation and some
even putting on weight over the winter months.
Female Snowy Owls are bigger than
males, and Alexander Chang and Karen Wiebe of the University of Saskatchewan
expected that their dominant behavior would give females access to greater food
resources during the challenging winter season. Their results bore this out --
females tended to be in better condition than males, and adults, with their
greater hunting experience, tended to be in better condition than juveniles.
It's widely believed that Snowy
Owls that winter south of the Arctic tend to be struggling, starving birds that
only move south because they can't find enough to eat at home, but few of the
adults captured in the wild showed signs of starvation. Surprisingly, many of
the adult birds in the study actually increased their fat stores slightly over
the course of the winter. Well-insulated against the cold and not distracted by
the demands of reproduction, Snowy Owls may use winter as a time to recharge
and build up their reserves before returning to their breeding grounds.
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