Bufflehead Bucephala albeota Linnaeus       Field Guide IDs: NG-92; G-56; P-60; PW-pl 13; AE-pl 127; AW-pl 103; AM (I)-200 Nest Location Nest Type Eggs & Mating System Dev. & Parental Care Primary & 2ndary Diet.. Foraging Strategy F I: 29-31 (28-33) DAYS PRECOCIAL 2 2 feet -10 feet (To 50 feet) BANK F 8-10 (6-12) MONOG F: 50-55 DAYS F BREEDING: : Mixed conifer-deciduous woodland near lake, pond. 1 brood. DISPLAYS: See: Duck Displays NEST: Usu within 650' of water; in natural or woodpecker-excavated (esp flicker) cavity. Where cavities scarce, will use burrow in earthen bank. Unlined or use remnants of previous nesters; down added. Perennial. EGGS: Ivory-yellow/light olive-buff. 1.8" (46 mm). DIET: Mostly aquatic insects and seeds of aquatic veg in fresh- and brackish-water habitats; crustaceans, snails, other mollusks and some aquatic veg in saltwater habitats. Fish important in winter. CONSERVATION: Winters s to c Mexico. Will use nest boxes where tree cavities scarce. NOTES: Long-term pair bond; strong fidelity to breeding and wintering areas. Young remain in nest for 24-36 hours; merging of broods is uncommon. Paired goldeneyes usu dominate territory-defending Bufflehead, but Bufflehead can expel goldeneye yearlings, females, and unpaired males. Yearlings and failed nesters (females) "prospect" for future nest sites while other females are incubating, or shortly after hatching. When feeding in small groups, one sentry usu stays on surface while others dive. STANFORD. NOTES: Uncommon winter visitor in more open, deeper water at Lagunita. ESSAYS: Dabblers vs. Divers; Sleeping Sentries; Interspecific Territoriality REFERENCES: Eadie and Gauthier, 1985; Erskine, 1972; Gauthier, 1987; Gooders and Boyer, 1986; Savard, 1982.