Date: 10/17/18 3:33 am From: Lars Norgren <larspernorgren...> Subject: [obol] Re: Photo: Aleutian Goose Ankeny NWR
If one scans a few thousand minima Cacklers("true"Cacklers) it is likely individuals with supplementary white on the head or neck will be detected. A bird with or without a white band at the base of the neck may have a white patch on the throat, sort of a supplement to the cheek patch. I have seen others that I don't recall in detail. I have heard that Cackling Geese are genetically closer to Red-breasted Geese than Canada Geese. I 'm guessing these are ancestral traits rather than leucism or hybrids. The neck ring can occur in Dusky Canada Geese and Taverner's Cackling Geese, although it is typically faint and narrower than the neck rings on minima and Aleutian Cacklers. Growing up in Corvallis l took wintering geese for granted. I now realize how lucky we are. Numbers have increased by an order of magnitude over the decades, and variety as well.
On Tue, Oct 16, 2018, 11:40 PM David Irons <llsdirons...> wrote:
> Greetings All, > > I would like to point out that the small goose that Jim Leonard > photographed at Ankeny NWR is a *minima *(Ridgway's Cackling Goose) and > not an Aleutian Cackling Goose (*B. h. leucopareia*). > > It is not particularly unusual for adult Ridgway's to show a conspicuous > white neck collar causing them to routinely be misidentified as Aleutians. > Aleutians winter almost exclusively in the Central Valley of California and > their migratory route past/through Oregon is almost entirely coastal. They > are at best rare in the Willamette Valley. In many years of looking for > them in the Valley Cackler flocks, I've only seen a few individuals and > couple small flocks. > > Note that this bird has a dark chestnut breast that is very glossy. > Aleutians are much paler breasted with no glossiness. Also, the head shape > of an Aleutian is much more boxy with a very pronounced forecrown (not > shown by this bird). Finally, the bill of an Aleutian is noticeably larger > than what is shown by this bird and the white cheek patch should be broader > as well. > > A broad and complete or mostly complete white neck collar on a Cackling > Goose does not make it an Aleutian. If you look through the large > essentially pure flocks of *minima* that winter in the Willamette Valley > you will see plenty of birds with conspicuous white neck collars. > > Dave Irons > Beaverton, OR > > ------------------------------ > *From:* <obol-bounce...> <obol-bounce...> on behalf > of Jim Leonard <photojleonard...> > *Sent:* Wednesday, October 17, 2018 4:11 AM > *To:* obol > *Subject:* [obol] Photo: Aleutian Goose Ankeny NWR > > I have never noticed or photographed an Aleutian Goose. A bird watcher > pointed it out in a flock of Canada and Cackler Geese today at Pintail > Marsh at Ankeny NWR. There were a couple of more in the flock. Photo by > Jim Leonard. Click on link below for photo. > > https://photos.app.goo.gl/huKN8TvAvZCLY4JQA > > >