From: <cobirds...> <cobirds...> on behalf of Jeff Percell <jeff.percell...>
Sent: Friday, March 26, 2021 10:08 AM
To: Colorado Birds <cobirds...>
Subject: Re: [cobirds] Boulder White Goose ID
I just now saw your post, but I went out yesterday and spent some time observing from both Prince Lake No 2 and Erie Lake (Reservoir according to eBird), as this (presumably same) bird that has been previously reported a few times this week from Erie Lake.
I was able to get better views from the Erie Lake side, but still not great photos. I posted several to my checklists below. I believe it to be a Ross's Goose based on the short stubby bill, completely lacking a grin patch. To me it appeared smaller than the nearby Canadas, which there was also some Cacklers on the lake as well.
I'd certainly appreciate any feedback on the ID, as this would be my first Ross's Goose.
On Thursday, March 25, 2021 at 2:17:12 PM UTC-6 David Waltman wrote:
The bill is smaller than on a Snow Goose which I think comes from part Ross’s. Also, the base of the bill is almost straight like a Ross’s instead of an arc like a Snow.
On 03/25/2021 12:59 PM 'Deborah Carstensen' via Colorado Birds <cob......> wrote:
What are the attributes cause you to think it’s part Ross’s goose? Thanks for the thoughts on that.
Deb Carstensen, Arapahoe county
Sent from my iPhone
On Mar 25, 2021, at 8:14 AM, DAVID J WALTMAN <djwa......> wrote:
Yesterday, 24 March, I photographed an interesting white goose at Prince Lake #2. It was roughly the size of nearby Canada Geese, too big for a Ross's Goose. The bill was too large for Ross's and did not have the perfectly straight vertical base of a Ross's. The head was not perfectly round like a Ross's. The bill appeared too small for a Canada Goose and did not have a significant grin patch. In summary, the head features were intermediate between Ross's and Snow. I conclude that this is a Ross's Goose x Snow Goose hybrid. See attached photo.