This may have some interest for some of you.
> From: Jean Iron <[log in to unmask]>
> Date: December 8, 2007 8:36:46 PM EST (CA)
> To: [log in to unmask]
> Subject: [Ontbirds]Great Gray Owls: Aging & Variation
> With today's report of a Great Gray Owl from Wye Marsh in Simcoe
> County and last Monday's sighting in Algonquin Park, we may see
> more Great Grays in southern Ontario. The last irruption of Great
> Gray Owls, one of the largest ever recorded, was in the winter
> 2004-2005. It was fully documented in three major articles in the
> December 2005 issue of Ontario Birds 23(3):105-160. In that flight
> there was only one confirmed first year bird (Mark Peck, pers.
> comm.). Most were adults with considerable old and faded
> feathering, which normally would have been molted, but was retained
> because of food stress (no voles). The lack of voles in 2004 also
> explained the absence of first year birds because most Great Grays
> did not breed or failed. This year's vole crash occurred much later
> (fall 2007 compared to spring 2004) so there should be
> proportionally more first year birds this winter.
> If you see a Great Gray Owl, try aging it using a scope. They are
> fairly easy to age as either first year or adult. See our online
> article "Aging and Variation of Great Gray Owls" <http://
> www.jeaniron.ca/GreatGrays/index.htm>. Using photos we discuss the
> plumages and molts, subspecies, morphs, albinism, melanism, and
> telling males from females.
> Please give tame boreal forest owls the space to hunt. Do not
> pursue them paparazzi-style. They are hungry and often starving.
> Ron Pittaway and Jean Iron
> Minden and Toronto ON
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