Bufflehead

Like many diving ducks, the Bufflehead does not nest in New Hampshire. The core of its breeding range is in western Canada and Alaska, with a few also nesting in the northern Rockies of the United States. Old nesting records as close as Maine occurred before extensive forest clearing in the Northeast, and now it breeds no closer than western Quebec. Like its relatives the goldeneyes, the Bufflehead is a cavity nester, and is thus found only in wooded areas during the breeding season. These are small ducks, and most nesting occurs in cavities excavated by Northern Flickers, although nest boxes are also readily used. On their freshwater breeding grounds Buffleheads feed almost entirely on insects including the larvae of dragonflies and midges.

In New Hampshire, the Bufflehead is a common migrant on lakes, ponds, and large rivers across the state, and winters primarily in sheltered coastal waters including Great Bay. Most of the eastern winter population is concentrated in the mid-Atlantic region, with many also in the Great Lakes. Winter prey in saltwater consists of mollusks, crustaceans, and sometimes small fish.

Buffleheads, like other ducks that breed in forested portions of Canada, show stable or increasing populations. Numbers on winter surveys in the Northeast appear stable, with fluctuations that likely reflect variation in open water which affect how birds are concentrated during the survey period.