Thursday 21 March 2013

Barred Owl irruption

Tonight on my way home from work I saw a Barred Owl...this has been a pretty regular occurrence this year and I am already up to 17 observations! Last year with a similar length commute through similarly good Barred Owl territory I had 6 observations by this date.
Barred Owl in Prince Edward County on Feb 23, 2013

So why the difference?  It seems that Barred Owls are more conspicuous this year partly because they are very hungry, so they are out earlier in the evening, later in the morning and sometimes all day trying to find some food.  It seems that hunger has also pushed more further south this winter. Barred Owls showed up on several Christmas Bird Counts where they don't normally (like the Kitchener count, where 2 were found on count day). Just check out the eBird map for this January-March:
Barred Owls reported to eBird during January to March 21, 2013
 And compare that to last year's map for the same period:
Barred Owls reported to eBird during January to March 2012
It seems like a good guess that for the same reasons that pretty much every irruptive bird species left most of the northern forests this winter (lack of tree seed crops) that small mammal populations have also dropped off, leaving Barred Owls (and Great Grays, Northern Hawk and Boreal Owls) with no choice but to head south in search of better foraging grounds. It likely also helps that it seems like Barred Owls had a pretty good breeding season: the Ontario Nocturnal Owl Survey reported a record high count of Barred Owls last spring and most of the Barred Owls I have seen and photographed have been young (born in 2012) birds.

Barred Owls were likely once common in forested southern Ontario but they are surprisingly rare there, with only very scattered individual pairs south of Toronto- check out the Ontario Breeding Bird Atlas maps to see what I mean. As forests mature in southern Ontario though maybe these big irruptions will help re-establish the species there.

3 comments:

  1. I've been watching and photographing a pair of Barred Owls in Woodstock.

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  2. Today, I seen a Barred Owl in the Heber Downs conservation forest in Whitby, Ontario....Followed me and my dog along a path for awhile..Awesome animals!

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