There is a large raft of at least 1500 Greater and Lesser Scaup located far offshore at the Allen Point end of the South Hero-Colchester Causeway. Also, I saw a flock of 145 Common Goldeneye there this afternoon.
If you go be aware that the road to Allen Point is blocked about 100 yards from the parking lot. I drove as far as I could, then backed out until I could turn my car around. Alternatively, it's probably safer to park at the beginning of the access road and walk in.