Canada/Cackling Geese & subspecies: Alaska (Anchorage)

[adrian]

These geese were photographed at the mouth of Ship Creek in Anchorage, Alaska, on June 2, 2018. I believe them to be Dusky Canada Geese (Branta canadensis occidentalis. However, this subspecies group (Dusky/Vancouver Canada Geese (occidentalis/fulva)) is flagged as rare in eBird, and I'm not sure Dusky Canada Goose actually does make it into the Anchorage area. However, the group of geese (only two photographed, silly me) looked as a whole considerably darker breasted and darker overall than our local Canada Geese on the East Coast of the US (subspecies maxima and canadensis). I believe most of my attached photos show this except for one in which the color is more washed out by lighting effects. Though the dark coloration overall would be in line with the minima subspecies of Cackling Goose, which would occur in the area, the birds seemed too large and long-billed for any subspecies of Cackling Goose (and too dark for Taverner's).

All photos show the same bird. In the one with two birds, the bird pictured in the other photos is the goose in the back.

I'd love to hear thoughts on these birds' subspecies, but would also appreciate simple confirmation that they are not Cackling Geese, as I admittedly have no experience with any of the western subspecies of Cackling Goose.

[adrian]

Just bumping this up since nobody responded.

[akiley]

I agree that these likely aren't Cackling. But I don't have experience with the western subspecies either. 

[Jim W]

I've been watching for a response a well.  Last summer I got a picture of some flying geese in Anchorage (Potter's Marsh if I remember correctly) and thought they looked pretty dark as well.  I've been doing some scouting around, but have found nothing definitive.  Everything I've found says Dusky breed exclusively in Copper River Delta (which is maybe 100 miles away from Anchorage as the goose flies) and on some nearby islands where they have been introduced.  But I've seen no reference to them ever being seen in Anchorage.  On my personal checklist I filed the picture as "possible Dusky", but to be honest I am becoming skeptical they are really Dusky.

I found a pretty good write-up on them:

https://www.dfw.state.or.us/resources/hunting/waterfowl/goose-permits/docs/goosefieldguide_ch3_dusky.pdf

[adrian]

Checking eBird, there are scattered reports of one to two photographed birds around the Anchorage area, so there seems at least to be some precedence for occurrence of this subspecies there. I think I'll report at least one bird as dusky to eBird, with these photos, and see what the reviewer says. The fact that they all struck me in the field as distinctly darker-breasted than eastern birds made me assume that dusky occurred regularly there and that the whole flock consisted of them, hence my confusion now. 

Thanks for your help.