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>> On 2014-03-10, at 1 --047d7beb9490a0291604f458c721 Content-Type: text/plain; charset=ISO-8859-1 Yes, the key though is, on a regular basis. Randy _________________________________ RF Lauff Way in the boonies of Antigonish County, NS. On 11 March 2014 14:51, Shouty McShoutsalot <desolatechair@gmail.com> wrote: > 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