Buffleheads primarily eat aquatic invertebrates and some seeds. Their freshwater diet consists of mostly insects like damselfly larvae, dragonfly larvae, midge larvae, water boatmen, mayfly larvae, caddisfly larvae and other insects. In saltwater habitats, a variety of arthropods and molluscs make up their diet. Buffleheads on the Pacific coast have been recorded consuming herring eggs in multi-species flocks and they occasionally eat fish like sculpins and ratfish. Prey is swallowed while submerged under the water. Buffleheads prefer to feed in water less than 3 meters deep. All of their food is acquired by diving except for downy young, who will dabble when first taking to the water.
Buffleheads' diet varies seasonally and by habitat. In the fall, pondweed seeds, sedges, bulrushes, and mare’s tail become important to the bufflehead diet. The literature reports that avian egg shells and bones have also been found in their stomachs. Female buffleheads that consumed mostly gastropods during egg-laying were found to have higher egg production. Eggs were also found to be larger with stronger shells. Gastropod consumption peaks during incubation.
Animal Foods: amphibians; fish; insects; mollusks; aquatic crustaceans; other marine invertebrates
Plant Foods: roots and tubers; wood, bark, or stems; seeds, grains, and nuts
Primary Diet: carnivore (Insectivore , Eats non-insect arthropods, Molluscivore )
Buffleheads are vulnerable to an assortment of predators that include birds of prey and mammals. Included in this list are peregrine falcons (Falco peregrinus), snowy owls (Nyctea scandiaca), and bald eagles (Haliaeetus leucocephalus), and possibly great horned owls (Bubo virginianus) and Cooper’s hawks (Accipiter cooperii). Weasels (Mustela) including mink (Neovison vison) and also squirrels (Sciuridae) and black bears (Ursus americanus) have been reported to feed on eggs in nest boxes. Female buffleheads are particularly vulnerable when perched on the nest, and eggs are vulnerable while females forage.
Known Predators:
Buffleheads are small diving ducks that exhibit strong sexual dimorphism. Males with breeding plumage are predominately black and white, with a black head and back that appears iridescent green and purple. They have a white underbelly and a distinguishing large white patch extending from the nape of the neck to the crown of the head. Males have blue-gray bills and pink webbed feet. Females are similar in plumage to male yearlings. They are grey on the bottom and brown on top with a white patch on the sides of the head. Both male yearlings and adult females have bills that are dark gray to black and legs and toes that are dark pink while webbed feet are brown. The ear patch of female buffleheads is more defined than the that of yearling males. The downy coats of hatchlings are black to dark grey with a white patched cheeks, throats, lower breasts, and bellies.
Buffleheads weigh 270 to 513 grams and are 32 to 40 cm long. Their wingspan is 16.9 to 17.5 cm long. Sexual dimorphism is exhibited in their size as well. Adult males weigh 450 grams on average and are 35 to 40 cm long, while females weigh 325 grams on average and are 32 to 35 cm long. Their folded wings are 18 cm or less in adults and their tails are less than 8 cm long.
Adult males are sometimes mistaken for common goldeneyes (Bucephala clangula), Barrow’s goldeneyes (<< Bucephala islandica>>) and hooded mergansers (Lophodytes cucullatus). Unlike buffleheads, goldeneyes have a white patch that starts below the eye and extends towards the beak and they both have golden eyes. Hooded mergansers are larger and have a fan-shaped white patch on their heads. Unlike bufflehead males, their chests and wings haave white stripes and a brownish or golden brown underside.
Range mass: 270 to 513 g.
Range length: 32 to 40 cm.
Range wingspan: 16.9 to 17.5 cm.
Sexual Dimorphism: male larger; sexes colored or patterned differently; male more colorful
Other Physical Features: endothermic ; bilateral symmetry
Buffleheads live an estimated 2.5 years for males and 2.3 years for females. In rare cases, adults live very long and the record for the oldest adult is 18.7 years old. However, information on survivorship is limited. The most recent survivorship data available (1969 to 1973) was generated in New York State and was obtained by banding and recovering birds. From these data it was estimated that annual survivorship of females is between 61 to 73%, and 58 to 70% for males. Because the sample size was particularly small, (56 to 159 birds of each sex) the accuracy of these estimates is not known.
Range lifespan
Status: wild: 18.7 (high) years.
Average lifespan
Status: wild: 2.5 years.
Average lifespan
Status: wild: 2.5 years.
Average lifespan
Status: wild: 224 months.
Buffleheads live in boreal forests and aspen parklands as well as seasonally-flooded wetlands and estuaries. They can be found along ecotones, and in marshes, farmlands, grasslands, and open waters. They prefer ponds and small lakes with no drainage while breeding. During migration, they use rivers and available water bodies as temporary habitat. Their winter habitat includes salty bodies of water like marshes, coastlines, and estuaries with shelter. They are not found at high mountain elevations.
Habitat Regions: temperate ; terrestrial ; saltwater or marine ; freshwater
Terrestrial Biomes: taiga ; savanna or grassland ; forest ; scrub forest
Aquatic Biomes: lakes and ponds; rivers and streams; temporary pools; coastal ; brackish water
Wetlands: marsh ; swamp ; bog
Other Habitat Features: suburban ; agricultural ; riparian ; estuarine
Buffleheads are native to North America. Their summer breeding range includes central Alaska and extends south to British Columbia and east to Saskatchewan. Isolated breeding populations can also be found throughout the northern United States and in Quebec. Their winter distribution is generally split into two populations, one on the east coast and the other on the west coast of North America. The east coast population is usually found from New Jersey to North Carolina, and can be reaches up to the Bay of Fundy in New Brunswick, Canada. The west coast population is concentrated in British Columbia, Washington, and California. The most substantial winter confluence occurs on British Columbia’s Vancouver Island and the Californian coast. They are less likely to be found moving inland from the western Klamath Basin in California and Oregon toward the Mississippi River.
Biogeographic Regions: nearctic (Native )
Buffleheads disperse seeds in their environment. They compete for nests with Barrow’s goldeneyes (Bucephala islandica), common goldeneyes (Bucephala clangula), squirrels (Sciuridae), European starlings (Sturnus vulgaris) and northern flickers (Colaptes auratus).
Like many ducks, buffleheads are prone to infection by a variety of parasites. When comparing buffleheads to other ducks, however, the abundance of parasitic species is modest. By examining the gizzards and intestines of adult buffleheads several species of roundworms, flukes, tapeworms, and thorny-headed worms were found. The roundworm species found were: Amidostomum acutum, Capillaria anatis, Capillaria contorta, Echinuria parva, Ecinuria uncinata, NematodaSchistorophus, Streptocara crassicauda, Streptocara formosensis, Tetrameres crami, Tetrameres fissipina, and Tetrameres spinosa. The flukes found were: Apatemon canadensis, Apatemon gracilis, Cotylurus strigeoides, Dendritobilharzia pulverulenta, Echinoparypthium recurvatum, Echinostoma trivolvis, Gyrosoma marilae, Maritrema obstipum, Notochotylus attenuatus, Odhneria odhneri, Philophthalmus gralli, Plagiorchis elegans, Prosthogonimus cuneatus, Pseudosplotrema, Psilochasmus oxyurus, Strigea, and Zygocotyle lunata. The tapeworms found were: Abortilepis, Aploparaksis, Cloacotaenia, Cloacotaenia megalops, Dicranotaenia multisticta, Diorchis bulbodes, Diploposthe laevis, Fimbriaria, Gastrotaenia cygni, Hymenolepis, Lateriporus skrjabini, Microsomacanthus collaris, Microsomacanthus melanittae, Microsomacanthus parvula, Platyscolex ciliata, Retinometra albeola, and Shistocephalus. Finally, the following thorny-headed worms found were: Corynosoma constrictum, Polymorphus acutis, Polymorphus marilis, and Polymorphus obtusus.
Of particular interest is that buffleheads appear to be the only duck with the tapeworm Retinometra albeolae. Leeches (Theromyzon rude, Theromyzon tesulatum, and Theromyzon bifarium) may infest their upper respiratory tract as well as their eyes. Bufflehead ducklings are more prone to leeches. A trematode in the family Schistosomatidae has been observed in the arteries. Renal coccidia also have been observed. Additionally, avian cholera (Pasteurella multocida), avian malaria (Plasmodium relictum), and avian influenza all have been identified in buffleheads. The literature states that little is known about the impacts of parasites and disease on buffleheads.
Ecosystem Impact: disperses seeds
Commensal/Parasitic Species:
During the winter and fall months the habitat of buffleheads is prime duck hunting range, so they are a target for hunters. Buffleheads make up 1 to 1.5% of all ducks killed in the U.S. and 1.5 to 2% in Canada. During 2009, in the Atlantic Flyway of Georgia, Maine and Maryland, 17,947 buffleheads were harvested. In 2008, there were 27,154 were harvested. Buffleheads also eat many types of insects, some of which are pests to humans.
Positive Impacts: food ; controls pest population
There are no adverse effects of Bucephala albeola on humans.
Buffleheads are listed as least concern on the IUCN Red List and do not have special status on US government lists. Previously, they were threatened by overshooting at the end of the 19th and beginning 20th century. Toxic contaminants are a current threat as well. Buffleheads collected around Long Island, NY, had low levels of polychlorinated biphenyls (PCBs) and mercury in their bodies. However, when compared to other dangers, habitat degradation is probably their biggest threat. Aspen nesting habitat has been replaced over the last 100 years in western North America with agricultural land, and clear-cutting for lumber continues to reduce the availability of nesting habitat. Nest boxes have been installed in some areas to supplement nesting habitat. It is important that these boxes be placed in conifer-heavy areas and the box openings be the correct size and mimic their natural nesting preferences. These specifications limit competition with other cavity-nesters.
US Migratory Bird Act: no special status
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
IUCN Red List of Threatened Species: least concern
Buffleheads find prey underwater by sight, and they communicate through vocalizations and displays. Courting bufflehead males bob their heads and produce a loud raspy noise. In late winter and spring, they emit a low snarling grunts. Females make a loud deep throated vocalization while following males during leading displays. Females use a distinct low note to call their young which speeds up and increases in volume if she becomes distressed. Buffleheads display a head-forward posture and raised wing feathers when they are threatened or when protecting their territory or brood. Males protect their territory by posturing next to other male buffleheads. This includes a head-forward posture, flapping wings, and a raised tail. Once this display ends, they part ways. Wing beating following the toe to toe display is thought to be a sign of concession by the loser.
Communication Channels: visual ; acoustic
Other Communication Modes: duets
Perception Channels: visual ; tactile ; acoustic ; chemical
Buffleheads generally form a mating pair that stays together during the season and in subsequent seasons. Less frequently, males pair with a second female after the first has finished laying her eggs. Courtship behavior occurs throughout the year and facilitates seasonal pairing of couples. Buffleheads use an array of physical displays and vocalizations during courtship. Males bob their heads and fly low over females to display their black and white underside and their pink legs, and then land with their feet straight as if water skiing. Paired birds display a “following” behavior where the female swims behind the male. The male stretches his neck upward and the female extends her neck back while she follows behind him. Buffleheads use displays both before and after copulation. Males also perform displays after threat or aggression from other males.
Mating System: monogamous
Buffleheads breed once per year from late winter to early April. Breeding females lay a single clutch between late April and mid-May with an average of 9 eggs per clutch. Female buffleheads typically lay their eggs close to the same date each year, but second and third-year breeding females lay 4 to 9 days earlier than first year breeders. Their eggs are olive-buff colored. On average, they measure 50 by 36 mm and weigh 36.68 g. Females incubate the eggs for 30 days while males leave to molt. When leaving the nest to feed during the incubation period, females cover their eggs with feathers.
Buffleheads use nests constructed by other species. Their nests are hollowed out cavities in trees usually within 15 m of a body of water and above flood plain level. Nests are often found in poplars and aspen, although pine trees are a favorite in the western United States. Nests are bare and buffleheads do not add material to their nests. Female buffleheads scout out their nest location up to a year in advance. If the desired nest is occupied when she returns, she searches for a new site with the male. Females only 1 year old have been observed searching for potential nest sites although they do not begin breeding until age 2. Two females have been documented sharing a same nest; however, one may evict the other that leaves the nest to feed. The average nest entrance is approximately 7 cm in diameter and the cavity diameter is 11.5 to 21 cm with a depth around 33.8 cm. Larger cavities are normally avoided because they are favored by goldeneyes (Bucephala islandica and Bucephala clangula). Goldeneyes can kill buffleheads in larger nests, but cannot enter the smaller entrances where buffleheads nest.
Bufflehead chicks hatch after 28 to 35 days. They typically hatch within a span of 12 hours, but may take up to 36 hours from first to last. It is thought that late hatching eggs are laid during incubation. Precocial chicks are born with their eyes open and fully covered in down, with a mass around 23.8 g. Buffleheads are able walk as soon as their plumage dries out. Young buffleheads are nurtured intently during and after hatching. Newly hatched chicks live in the nest for 1 to 2 days and are then encouraged to jump from the nest hole. New mother buffleheads protect their brood for 3 to 6 weeks, at which point the young buffleheads are considered independent.
Young ducklings are good swimmers, feeding on insects (92-100% of the time) on the water and dabbling for vegetation. Their diving abilities develop in the first few days and become the predominant mode of feeding. In fact, downy young spend 24% of their time diving. Growth rates vary among individuals which is typical of precocial birds. By day 20, the juvenile contour feathers begin to emerge with wing feathers appearing at day 23. Their belly feathers appear next and the head, back and neck feathers appear last. By day 40, males are apparently larger than their sisters. Plumage is complete after day 50 and the chicks fledge in 45 to 55 days. They reach reproductive maturity at 2 years.
Breeding interval: Buffleheads breed once per year from late winter to early April.
Breeding season: Late winter to early April
Range eggs per season: 6 to 11.
Range time to hatching: 28 to 33 days.
Range fledging age: 45 to 55 days.
Range time to independence: 3 to 6 weeks.
Average age at sexual or reproductive maturity (female): 2 years.
Average age at sexual or reproductive maturity (male): 2 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous
Average eggs per season: 8.
Male buffleheads stay with their mates during egg laying and for part of the incubation period. Females alone attend to the brood and defend their territory. They nurture their young for the first 2 to 3 weeks after hatching. The young huddle tightly together on both sides of the female on the shore or a floating log. Young buffleheads gather tightly and close behind their mother if she gives an alarm call. In British Columbia, 34% of broods had at least one exchange of young buffleheads between mothers, usually during a fight between them. Occasionally an entire brood is acquired by a female bufflehead that won a territorial fight. Bufflehead mothers protect their brood for up to 6 weeks, when the chicks are independent.
Parental Investment: precocial ; female parental care ; pre-fertilization (Protecting: Male); pre-hatching/birth (Protecting: Male, Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Provisioning: Female, Protecting: Female)
A small, teal-sized duck (13-15 inches), the male Bufflehead may be most easily identified by the large white patch on the back of its head. Other distinguishing characteristics include its iridescent green head, white body, and patchy black-and-white wings visible in flight. The female Bufflehead is dull brown above with a white belly, light brown flanks, and a smaller white patch behind the eye. Duck hunters refer to this species as the “butterball” in reference to the male’s large white head patch. The Bufflehead breeds primarily in west-central Canada, in central Alaska, and at higher elevations in the Rocky Mountains. Small numbers of Buffleheads breed elsewhere in western North America, extending east to the Great Lakes. This species migrates south for the winter, when it may be found unevenly distributed across the southern half of North America. Buffleheads are found locally in the interior of their winter range, but are more common along the Atlantic and Pacific coasts north to Nova Scotia and Alaska, respectively. In summer, Buffleheads breed on ponds and lakes near forests. Buffleheads are particularly attracted to forests inhabited by the Northern Flicker (Colaptes auratus) because this species builds its nest in old Flicker nest cavities. In winter, Buffleheads may be found on sheltered saltwater bays and estuaries or, inland, on large lakes or rivers. This species primarily eats small animals, such as crustaceans, mollusks, and insects when available. One of several species of “diving ducks” in North America, Buffleheads may be observed submerging themselves to feed in the water or on the bottom. In winter, they may also be observed in small flocks on large, slow-moving bodies of water. This species is primarily active during the day.
A small, teal-sized duck (13-15 inches), the male Bufflehead may be most easily identified by the large white patch on the back of its head. Other distinguishing characteristics include its iridescent green head, white body, and patchy black-and-white wings visible in flight. The female Bufflehead is dull brown above with a white belly, light brown flanks, and a smaller white patch behind the eye. Duck hunters refer to this species as the “butterball” in reference to the male’s large white head patch. The Bufflehead breeds primarily in west-central Canada, in central Alaska, and at higher elevations in the Rocky Mountains. Small numbers of Buffleheads breed elsewhere in western North America, extending east to the Great Lakes. This species migrates south for the winter, when it may be found unevenly distributed across the southern half of North America. Buffleheads are found locally in the interior of their winter range, but are more common along the Atlantic and Pacific coasts north to Nova Scotia and Alaska, respectively. In summer, Buffleheads breed on ponds and lakes near forests. Buffleheads are particularly attracted to forests inhabited by the Northern Flicker (Colaptes auratus) because this species builds its nest in old Flicker nest cavities. In winter, Buffleheads may be found on sheltered saltwater bays and estuaries or, inland, on large lakes or rivers. This species primarily eats small animals, such as crustaceans, mollusks, and insects when available. One of several species of “diving ducks” in North America, Buffleheads may be observed submerging themselves to feed in the water or on the bottom. In winter, they may also be observed in small flocks on large, slow-moving bodies of water. This species is primarily active during the day.
The bufflehead (Bucephala albeola) is a small sea duck of the genus Bucephala, the goldeneyes. This species was first described by Carl Linnaeus in his landmark 1758 10th edition of Systema Naturae as Anas albeola.[2]
The genus name is derived from ancient Greek boukephalos, "bullheaded", from bous, "bull", and kephale, "head", a reference to the oddly bulbous head shape of the species. The species name albeola is from Latin albus, "white".[3] The English name is a combination of buffalo and head, again referring to the head shape.[4] This is most noticeable when the male puffs out the feathers on the head, thus greatly increasing the apparent size of the head.
The bufflehead ranges from 32–40 cm (13–16 in) long and weighs 270–550 g (9.5–19.4 oz), with the drakes larger than the females. Averaging 35.5 cm (14.0 in) and 370 g (13 oz), it rivals the green-winged teal as the smallest American duck. The bufflehead has a wingspan of 21.6 in (55 cm).[5]
Adult males are striking black and white, with iridescent green and purple heads and a large white patch behind the eye. Females are grey-toned with a smaller white patch behind the eye and a light underside.[6]
They are migratory and most of them winter in protected coastal waters, or open inland waters, on the east and west coasts of North America and the southern United States. They can also be observed wintering on the Great Lakes. The bufflehead is an extremely rare vagrant to western Europe. Their breeding habitat is wooded lakes and ponds in Alaska and Canada, almost entirely included in the boreal forest or taiga habitat. From 1966 - 2015, the bufflehead experienced a>1.5% yearly population increase throughout its breeding range.[7]
Buffleheads have evolved their small size to fit the nesting cavity of their "metabiotic" host, a woodpecker, the northern flicker.[8] Due to their small size, they are highly active, undertaking dives almost continuously while sustained by their high metabolism. They do not tend to collect in large flocks; groups are usually limited to small numbers. One duck serves as a sentry, watching for predators as the others in the group dive in search of food.[6] Buffleheads are amongst the last waterfowl to leave their breeding grounds and one of the world's most punctual migrants, arriving on their wintering grounds within a narrow margin of time.[9]
Buffleheads are monogamous,[8] and the females may return to the same nest site, year after year. They nest in cavities in trees, primarily aspens or poplars, using mostly old flicker nests, close (usually < 25 m (82 ft)) to water. Nest competitors include mountain bluebird (Sialia currucoides), tree swallow (Tachycineta bicolor), and European starling. There was one recorded instance of a female Barrow's goldeneye killing a bufflehead adult female and her brood. Smaller cavities are preferred because of less competition with the larger goldeneyes. Females may be killed on the nest by mammals, such as foxes (Vulpes and Urocyon sp.), weasels (Mustela and Neogale sp.) or mink (Neogale vison), and by goldeneyes over nest competition.
Average clutch size is nine (range six to 11), and eggs average 50.5 by 36.3 mm (1.99 by 1.43 in).[8] Incubation averages 30 days, and nest success is high (79% in one study) compared to ground-nesting species like the teal. A day after the last duckling hatches, the brood leaps from the nest cavity. The young fledge at 50–55 days of age.[10] Predators of adults include the peregrine falcon (Falco peregrinus), snowy owl (Bubo scandiacus), bald eagle (Haliaeetus leucocephalus), golden eagle (Aquila chrysaetos), red-tailed hawk (Buteo jamaicensis), great horned owl (Bubo virginianus), and Cooper's hawk (Accipiter cooperii).
These diving birds forage underwater. They prefer water depths of 1.2–4.5 m (3.9–14.8 ft).[6] In freshwater habitats, they eat primarily insects, and in saltwater, they feed predominantly on crustaceans and mollusks. Aquatic plants and fish eggs can often become locally important food items, as well.
Because of their striking plumage, highly active nature, and proximity to humans on waterfront properties, buffleheads are one of the most popular birds amongst bird watchers.[10] The bufflehead, also known as the spirit duck, was added to the coat of arms of the town of Sidney, British Columbia, in 1995.[11] Buffleheads are hunted and are considered a gamebird. In contrast to many other seaducks that have declined in recent decades, bufflehead numbers have remained relatively constant.[8] Habitat degradation is the major threat to this bird, since they depend on very limited coastal habitat on their wintering grounds, and very specific habitat in their boreal[12] breeding grounds. Although buffleheads do use man-made nest boxes, they still need the forest habitat to thrive.
The bufflehead (Bucephala albeola) is a small sea duck of the genus Bucephala, the goldeneyes. This species was first described by Carl Linnaeus in his landmark 1758 10th edition of Systema Naturae as Anas albeola.
The genus name is derived from ancient Greek boukephalos, "bullheaded", from bous, "bull", and kephale, "head", a reference to the oddly bulbous head shape of the species. The species name albeola is from Latin albus, "white". The English name is a combination of buffalo and head, again referring to the head shape. This is most noticeable when the male puffs out the feathers on the head, thus greatly increasing the apparent size of the head.
