[Tweeters] Snowy Owl Irruptions

dennispaulson at comcast.net dennispaulson at comcast.net
Wed Dec 4 12:40:41 PST 2013


Josh, that is really great, putting the differences among years clearly in perspective. Thanks for putting that together!

Dennis Paulson
Seattle
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Message: 1
Date: Tue, 3 Dec 2013 12:03:19 -0800
From: Josh Adams <xjoshx at gmail.com>
Subject: [Tweeters] Snowy Owl Irruptions
To: Tweeters <tweeters at u.washington.edu>

Hello Tweets,
I've seen a few posts referencing Snowy Owl irruptions on the east coast
along with optimism that this might indicate a third consecutive year of
irruption here on the west coast. I'm not an expert on the subject by any
means, but I've done enough reading in the Tweeters archives to play
"weather man." Despite a couple of recent sighting reports in Western
Washington, I believe we are well past the window when we should start
seeing Snowy Owls in any sort of significant irruptive year. In the three
major irruptive years I found (2005, 2011, and 2012), the owls consistently
started showing up in Western Washington in the second week of November.

Here were the dates of the first Western Washington reports I could find in
the Tweeters archives:
November 17 2005 - Birdbox report of Snowy Owl in Everett. Many sightings
after that.
November 13th 2011 - Snowy Owl in Ocean Shores. Within a week they were
appearing in many locations.
November 9th 2012 - Bud Anderson reports a Snowy Owl seen at Sea-Tac
airport, Two days later at least one Snowy made an appearance in Seattle
and sightings only increased from there.

On several occasions, we received a day or two advanced notice of birds
showing up in BC which could indicate an irruption year.

As you well know, we are well past the second week of November when the
owls should have started showing up. We certainly may (and apparently do)
have owls that will show up in western Washington, but nothing like either
of the last two years. The last two years have been incredible, and may end
up being the best two year stretch of Snowy Owl sightings in our lifetimes.

This year looks to be similar to the winter of 2008-2009, where the owls
irrupted in good numbers in the east, but not at all in the west.

For fun I made an animation of ebird sightings of the last 8 years of Snowy
Owl sightings in November across all of North America. I probably should
have kept going and added 2005 as well, but knowing that eBird has much
less data the farther back you go I didn't want to skew the results too
much.

Here is a link to the animation:
http://i.imgur.com/93OEG6K.gif

Josh Adams
Lynnwood, WA


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