Bufflehead

Bucephala albeota
STANFORD LOCATIONS:

Uncommon winter visitor in more open, deeper water at Lagunita.
  
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.
ESSAYS: Dabblers vs. Divers; Sleeping Sentries; Interspecific Territoriality.
REFERENCES: Eadie and Gauthier, 1985; Erskine, 1972; Gauthier, 1987; Gooders and Boyer, 1986; Savard, 1982.

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Except for Stanford Locations, the material in this species treatment is taken, with permission, from The Birder's Handbook (Paul Ehrlich, David Dobkin, & Darryl Wheye, Simon & Schuster, NY. 1988).