It is fairly uncommon to see all three merganser species in one place in CT. That occurred this evening on the Farmington River in Collinsville. Two Commons and one Hooded were joined by a Red-breasted Merganser, all actively feeding and working river along CT 179. The Hooded was not really feeding with them but at one point I had one of each species in my scope view simultaneously. First time I've seen that in quite awhile.
Common and Hooded both nest in the area. It was Ladies' Night on the river as all of the birds were females.