The ~1000 geese were taking off and heading north throughout the 15/20 minutes I was there, until about 100 geese were left.
Eventually the Ross's took off, disappearing into to the north. I didn't stick around long enough to see if it would return to the lake to roost for the night.
The Ross's Goose makes 130 birds for the year. The only regular waterfowl that I still haven't seen this year include Snow Goose (code 1), Eurasian Wigeon (code 3), Blue-winged Teal (code 1), and Harlequin Duck (code 3). Off to Niagara tomorrow!