[NatureNS] re Surviving Snowy Owls - What Next?

DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
References: <92470D8023567B4D8D50FBA6E5E9D00F0ECC195429@HCXMSP1.ca.lmco.com>
Date: Tue, 11 Mar 2014 14:51:29 -0300
From: Shouty McShoutsalot <desolatechair@gmail.com>
To: naturens <naturens@chebucto.ns.ca>
Precedence: bulk
Return-Path: <naturens-mml-owner@chebucto.ns.ca>
Original-Recipient: rfc822;"| (cd /csuite/info/Environment/FNSN/MList; /csuite/lib/arch2html)"

next message in archive
next message in thread
previous message in archive
previous message in thread
Index of Subjects

&gt; reproducing?  Will they return from whence they came e
--20cf302236d1aa3c6704f4585ea7
Content-Type: text/plain; charset=ISO-8859-1

If birds go south in the fall and return north in the spring on a regular
basis aren't they migrating and not irrupting?


On 11 March 2014 14:30, James Churchill <jameslchurchill@gmail.com> wrote:

> hi folks,
>
> The question of the relationship between plumage colour and survivability
> in the South (and North) is interesting...
> Although sometimes they are difficult to see in snow-covered environments,
> behaviourally, they are not that cryptic...using mounds, telephone poles,
> roof tops. A recent paper (IBIS, 2011, which, disclaimer, I haven't read)
> suggests that darker plumage is almost always absent from the most
> conspicuous areas of the body (face, throat, breast - although, those could
> be hidden quite easily with posture adjustments), perhaps suggesting a role
> of plumage colour in sexual signalling too...
>
> To build on Andy's ideas, eBird also now allows users to search for
> checklists containing images or videos and there is a wealth of Snowy data
> up there...any patterns in the plumage of birds by latitude, snow cover,
> date? (there are issues of differences in detectability of these owls
> related to plumage patterns and snow cover too that would have to be
> faced...)
>
> cheers,
> James.
>
>
>
> On Tue, Mar 11, 2014 at 1:39 PM, Andrew Horn <aghorn@dal.ca> wrote:
>
>>  Hi all,
>>
>>  We'll know a bit more about these winter irruptions thanks to Project
>> Snowstorm, whose website is full of useful info and very cool maps of the
>> movements of several individual owls: http://www.projectsnowstorm.org
>>
>>  The project has tagged snowy owls from Minnesota to Massachusetts with
>> transmitters that track their winter movements. It's a crowdfunded project
>> (thus the site's many pleas for funds) that was started to take advantage
>> of this winter's big irruption, since so little is known about where
>> wintering snowy owls go and why.
>>
>>  Cheers,
>> Andy
>>
>>
>>  On Mar 11, 2014, at 1:02 PM, James W. Wolford <jimwolford@eastlink.ca>
>> wrote:
>>
>>  My experience from Alberta in the 1960s & '70s was much like Lance just
>> discussed re Montreal area, that snowy owls came south every year, but the
>> numbers vary greatly from year to year.  And, as Lance says, it is assumed
>> that those overwintered owls that survive and are capable of heading back
>> toward the north do so.  Their northward destinations would be unknown
>> perhaps for the immatures, but definite for those that had previously
>> nested at least once.
>>
>>  I disagree with Jamie Simpson that because the southward irruptors have
>> no definite destination, other than some place with food, that they would
>> have no instinct or desire to head back to the north after winter.
>>
>>  I do recall one example of a snowy owl that stayed in Nova Scotia for
>> the summer.  It was very surprising one year in The Brothers Islands off
>> the Pubnico communities, and caused a lot of problems for the roseate terns
>> that were trying to raise young there.  Consult Ted d'Eon/D'Eon? on when
>> that happened, in the 1970s? or early 1980s?
>>
>>  Cheers from Jim in Wolfville.
>>
>> Begin forwarded message:
>>
>>  *From: *"Laviolette, Lance (EXP)" <lance.laviolette@lmco.com>
>>  *Date: *March 11, 2014 12:04:15 PM ADT
>>  *To: *"naturens@chebucto.ns.ca" <naturens@chebucto.ns.ca>
>>  *Subject: **Re: [NatureNS] Surviving Snowy Owls - What Next?*
>>  *Reply-To: *naturens@chebucto.ns.ca
>>
>>   Hi Jamie,
>>
>>  My take on this is that while this may be a food/territory driven
>> phenomena it is not simply a case of Snowy Owls, mostly young, being driven
>> south to never return. From my experience in the Montreal Region, many owls
>> make the trip south each year and have done so for a number of years. This
>> has been confirmed through individuals with unique physical characteristics
>> that could be used to identify them. They stay for the winter months and
>> then head back north. At least I believe they head back north. They
>> certainly leave southern Quebec.
>>
>>  Whether some of these birds remain through the summer or not is another
>> matter. There are a number of bird families that irrupt south. Along these
>> lines, every year Ron Pittaway publishes the winter finch forecast which
>> predicts which finch species will irrupt south in the coming winter. In
>> most cases the birds that irrupt south and survive head back north. However
>> there are a number of cases where northern species have bred in the south.
>> In Nova Scotia I would bet that a lot/most of the mainland Evening
>> Grosbeaks that are still breeding are a result of a huge irruption that
>> took place throughout eastern Canada in the 1970s (I think that's the time
>> frame).
>>
>>  So I'd say that irruptions serve both an immediate survival role,
>> sending excess population to other areas in search of food, and a mechanism
>> that may result in an expansion of the species' range. Some of Nova
>> Scotia's Snowy Owls may stay through the summer and perhaps survive. Some
>> may leave and return again next year.
>>
>>  All the best,
>>
>>  Lance
>>
>>  *Lance Laviolette*
>>  Glen Robertson, Ontario
>>
>>
>>  *From:* naturens-owner@chebucto.ns.ca [
>> mailto:naturens-owner@chebucto.ns.ca <naturens-owner@chebucto.ns.ca>] *On
>> Behalf Of *Shouty McShoutsalot
>> *Sent:* Tuesday, March 11, 2014 8:43 AM
>> *To:* naturens
>> *Subject:* EXTERNAL: Re: [NatureNS] Surviving Snowy Owls - What Next?
>>
>>  My understanding is that irruption and migration are two very different
>> behaviors, and that irruption is a diaspora - the animal leaves because it
>> is forced to, with no predefined destination as exists in a migration, and
>> thus no instinct to return to it's point of origin.
>>
>>
>>  On 10 March 2014 14:24, Paul Ruggles <cpruggles@eastlink.ca> wrote:
>>  Jamie,
>> I have been videoing two snowys for over a month at Lawrencetown beach.
>> They seem to have moved away in the past 2 weeks. I thought they might have
>> begun their migration back to the tundra? Have any of you seen any lately?
>> Paul.
>>
>>
>> On 2014-03-10, at 1