[Tweeters] Snowy Owl activity cycle

Dennis Paulson-IMAP dennispaulson at comcast.net
Thu Nov 16 12:20:36 PST 2017

Hello, all.

I finally decided that I needed to chime in on this.

Yes, Snowy Owls are diurnal, and of course they hunt during the day on their Arctic breeding grounds, but under what light conditions do you think they hunt when they are still in the Arctic in the winter? I think the technical term for the ability to be active throughout the 24-hour cycle is omnurnal. Quite a few mammals fit this description (can you think of any?) and at least a few birds, such as this one and any of the other owls that are resident at high latitudes.

In fact, when with us in the winter, they very commonly hunt at dusk and even into the night. As dusk falls, they become much more alert and active than when many of us see them during the day, and just as it’s getting dark they may set off to hunt, often over the water. How they get so many grebes and sandpipers, two of their common foods when they are with us, is by hunting when it is getting dark or is entirely dark. One or more birds on the South Levee of the Columbia River were taking Red Phalaropes at night. They do just as well under those conditions as a Great Horned Owl does, taking prey even as large as White-winged Scoters (Paul Bannick relayed that to me).

Another of their common prey items during the winter is rats, both Norway and Black Rats. The rats are nocturnal.

But I agree entirely with Ray that you are not “keeping them up” when you are visible to them during the day time. They are quite awake. Of course you shouldn’t actively disturb them, but as he said, with the great number of visitors to the owls at Damon Point, if they were disturbed as much as has often been feared, they wouldn’t have hung around there.

Speaking of omnurnal, a Barred Owl was hunting squirrels in my yard at 9 am on Tuesday! It was unsuccessful and didn’t seem to faze the squirrels at all. I should add that I have never seen this before, but I know they do hunt during the daytime on occasion.

Dennis Paulson
Seattle, WA

On Nov 16, 2017, at 12:00 PM, tweeters-request at mailman1.u.washington.edu wrote:

> Date: Thu, 16 Nov 2017 01:58:59 +0000 (UTC)

> From: ray holden <rayleeholden at yahoo.com>

> Subject: [Tweeters] Snowing Owls Point of Information

> To: Tweeters Tweeters <tweeters at u.washington.edu>

> Message-ID: <171064973.1104259.1510797539379 at mail.yahoo.com>

> Content-Type: text/plain; charset="utf-8"


> Like everyone else I'll excited to hear that we are having a visitation from the North other than Santa and hope some may find their way to the south sound or Gray's Harbor area.

> Snowy owls are not nocturnal they are diurnal otherwise they wouldn't be able to eat in the nightless arctic summer. When you see them they will be active and seem to take cat like naps but you aren't keeping them awake or keeping them from hunting. During the last big outbreak and the following year echo the owls at Damon Pt. Ocean Shores were visited by hundreds of people, dozens a day even, and yet the flock stayed steady for the whole winter. Dead gulls and ducks on the beach testified that they were getting plenty to eat despite our human curiosity.

> For the best views take a scope or ask another birder to use theirs. I've never had anyone say no. Most people who got too close were trying to take pictures with dinky cameras or cell phone cameras and I think that generally they weren't birders who would ever read this anyway. For good pics that don't get too close you need a superzoom or a long lens DSLR and tripod.

> I sincerely hope to see another owl or two this year. With a roughly 7 year breakout cycle you never know when will be your last time.



> Ray Holden

> Olympia, WA

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