I’ll take your word for it that it appeared larger in the field - it’s certainly smaller than the Canadas but I can’t see it at all in image 3 - just some darker cackling and Canadas. I’m assuming it’s on the far right in image 1 ? but impossible to judge size from that. Were you using a telephoto?
Taverner’s are difficult to separate from Lesser Canada Geese btw although your bird does have a steep forehead and appropriately stubby bill.
I don’t think you will get a definitive ID here - I can only make a suggestion/educated guess!
Thank a lot for your help! Yes, this bird is only on photos 1 and 2. And it kept with the group of other Cackling Geese. They were among a huge group of Canada Geese resting on the lake, I would say 3 - 5 thousand. Anyway, thank you for guessing and educating
Richardson's Cacklers vary quite a bit in color as well, with some birds having a darker chest and some being quite frosty overall. The status of Taverner's in the East is very poorly known, but I think they are thought to wander less than Richardson's.