Nest: This species is not an obligate tree nester, and has been reported to use holes in banks or lava beds, rock crevices, ground under shrubs and on islands, haylofts, crows’ nests, and the outer walls of peat shelters for sheep in Iceland (Harris et al. 1954). However, the usual site is in dead stubs or trees such as aspen, Douglas-fir, and ponderosa pine within 100 feet of water (Palmer 1976). Deserted pileated woodpecker or common flicker cavities enlarged by natural decay are readily used (Palmer 1976). Cavity entrances from 3.0 to 3.9 inches in diameter, cavity depths between 9.8 and 52.9 inches, and cavity diameters between 6.5 and 9.0 inches have been reported (Johnsgard 1975). Nest boxes have been used around high lakes in the Cascade Mountains (Bellrose 1976). Food: Food of 71 adult Barrow’s goldeneyes consisted of 36 percent insects, 19 percent molluscs, 18 percent crustaceans, 4 percent other animals, and 22 percent plants (Cottom 1939). Naiads of dragonflies and damselflies, caddisfly and midge larvae, blue mussels, amphipods, isopods, and crayfish were important animal foods, and pondweeds and wild celery were primary plant foods. Bufflehead _Bucephala albeola_ L 10″ W 24″ [Illustration] Habitat: Buffleheads favor small ponds and lakes in open woodlands (Godfrey 1966). In British Columbia, most nesting is in the interior Douglas-fir zone while poplar communities are usually used in Alberta, and ponderosa pine types are preferred in California. Scattered breeding records in Oregon, Wyoming, and Idaho are primarily in subalpine lodgepole pine, and in Alaska (Erskine 1971) Engelmann spruce and cottonwood stands are used for nesting. Nest: Of 204 nests observed from California to Alaska, 107 were in aspen trees, 44 in Douglas-fir, 14 in balsam poplar and black cottonwood, 12 in ponderosa pine, 11 in poplar, and 16 in a few other coniferous and deciduous trees (Palmer 1976). Buffleheads prefer unaltered flicker holes in aspen. Dead trees close to (within 220 yards) or in water are preferred, and “bucket” or open top cavities are rarely used (Erskine 1971). Forestry practices that leave stubs near water while clearing away most ground litter and slash that might hinder ducklings from reaching water are to be encouraged. Nest boxes used by captive buffleheads had entrances 2⅞ inches wide with cavities 7 inches in diameter and 16 inches deep (Johnsgard 1975).