The male bufflehead stands out due to the large white patch on the back of his head and white underbelly. Close examination reveals that the “black” coloration on the male is glossy and iridescent. Females are brown with a small, discrete white “cheek”. Aquatic invertebrates, particularly insect larvae and various shellfish, are the favored foods of this diving duck, though they will also eat vegetation.
This small duck is a cavity nester and will often use cavities drilled by Northern flickers. While the bufflehead is primarily a bird of North America, wayward migrants have ended up in several different locations across the Northern Hemisphere.