Northern Prairie Wildlife Research Center
A large white wedge-shaped patch extending from the eye to the back of the head is characteristic of the adult male bufflehead in spring plummage.
Buffleheads generally winter on the Atlantic and Pacific coasts as far north as New England and British Columbia. They may also be found wintering on the Gulf Coast, in northern Mexico and inland in the United States to the ice line. Buffleheads are observed throughout North Dakota during both spring and fall migrations. Flock size is usually small and often only one or two birds are seen on a lake. They arrive early in spring but are one of the last to leave in the fall.
The bufflehead breeds primarily in the wooded regions of western Canada and eastern Alaska. Breeding is associated with woodland ponds and streams and the parkland transition zone between the prairies and the forest.
North Dakota is on the southern edge of the breeding range. The nesting population is limited to the Turtle Mountains (Bottineau County) and along the Souris River (McHenry County) within the J. Clark Salyer National Wildlife Refuge.
Buffleheads, like other diving ducks, patter along the water surface for some distance prior to take off.
Animal matter comprises a high percentage of the bufflehead's diet. Items eaten include aquatic insects, snails and particularly fish in winter. Buffleheads also eat seeds of aquatic plants.
Some of the bufflehead nests recorded in the Turtle Mountains have been in old flicker nest cavities in dead trees. The nest usually consists of a depression in the loose material at the bottom of the tree cavity and is lined with down plucked from the hen's breast during egg laying and incubation. From six to 14 dull light buff color eggs are laid, one each day, with most nests having from eight to ten eggs. The four-week incubation period begins full time when the last egg is laid. The male abandons the female when full time incubation begins.
After hatching the ducklings leap from the nest like wood ducks, and the brood then follows the female to water. Once on the water, the young feed mainly on aquatic insects, taking larger food items as they mature. The female remains with the brood for seven to eight weeks until the young can fly.