Quick Answers
Buffleheads and Harlequin ducks are two species of small sea ducks found in North America. The main differences between them are:
- Appearance – Buffleheads have a large white patch on the back of the head and black and white bodies. Harlequins are more colorful with blue, chestnut, and white patterns.
- Size – Buffleheads are the smallest North American diving ducks. Harlequins are slightly larger.
- Habitat – Buffleheads live mainly on small ponds and sheltered coastal habitats. Harlequins inhabit rocky shores and open water.
- Breeding – Buffleheads nest in tree cavities near water. Harlequins nest on the ground on islands or sheltered mainland sites.
- Diet – Both species eat mollusks, crustaceans, and insects, but buffleheads mostly dive for food while Harlequins dabble more.
Taxonomy and Identification
Buffleheads and Harlequin ducks belong to the genus Bucephala within the duck tribe Mergini. Mergini are often called “sea ducks” because they inhabit marine environments in winter. Their legs are set far back on their bodies to provide greater propulsion for diving underwater.
Buffleheads (Bucephala albeola) are the smallest diving ducks in North America. Their compact size allows them to escape from diving boxes that trap larger ducks. Males have a large white patch at the back of the head and a dark iridescent green head. Their bodies are mostly white with some black markings. Females are smaller and gray-brown with a diffuse white patch on the head.
Harlequin ducks (Histrionicus histrionicus) are slightly larger than buffleheads. Males have a blue-gray body with chestnut flanks and white markings. Females are brownish-gray with some white patches around the face and body. The white markings are more extensive in the Pacific population.
Range and Habitat
Buffleheads have a wide breeding range across Canada and Alaska and parts of the northern United States. They migrate south to winter along both coasts and inland, as far south as Mexico. Their preferred wintering habitats are sheltered marine waters, coastal ponds, lakes, and rivers.
Harlequins have a more northerly distribution. They breed along fast-moving streams and rivers in western mountain ranges from Alaska and Canada south to Idaho and Wyoming. Most birds winter along rocky coastlines from southern Alaska to central California, although some migrate inland to large lakes and rivers.
Breeding
Buffleheads start migrating north in February and March to reach their breeding grounds by late April or May. They are solitary nesters, requiring tree cavities close to water such as those made by northern flickers. Females line the cavity with down feathers plucked from their breast and lay 6-15 white eggs. Incubation lasts about 30 days. Ducklings leap from the nest cavity within one day of hatching and follow their mother to water where she cares for them until they fledge at 55-65 days.
Harlequins arrive on breeding streams and rivers starting in late April. Nesting begins in May and June. Harlequins nest on the ground on offshore islands or sheltered mainland sites close to rapids. The nest is concealed in thick vegetation and lined with down. Females lay 5-7 eggs that hatch in about 30 days. Ducklings leave the nest soon after hatching and follow their mother to a sheltered stream pool. They fledge in 40-50 days.
Diet and Feeding
Buffleheads and Harlequins have varied diets including insects, crustaceans, mollusks, and other small aquatic invertebrates. Buffleheads do most of their feeding by diving underwater, sometimes descending to depths over 20 feet. Their compact size allows them to maneuver easily to feed on insect larvae and small crustaceans. Harlequins dabble more at the water’s surface, but are also capable divers when searching for food around rocky shores. Both species transition to plant foods like seeds and aquatic vegetation in winter.
Foods Eaten
Bufflehead | Harlequin Duck |
---|---|
Insects | Insects |
Crustaceans | Crustaceans |
Mollusks | Mollusks |
Fish eggs and larvae | Fish eggs and larvae |
Aquatic plants (winter) | Aquatic plants (winter) |
Behavior
During the breeding season, male buffleheads compete for nest sites and mates. Their courtship displays involve head bobbing, puffing out feathers, and vocalizations. Outside of breeding, they are generally quiet ducks. They are sociable in winter, forming flocks of dozens or hundreds on open water. Buffleheads can dive to escape predators, flying underwater to pop up some distance away.
Harlequins are also mostly quiet and solitary nesters. Males perform an elaborate courtship dance on fast-moving water, bobbing vertically and throwing their heads back. Harlequins generally do not form large winter flocks, remaining in smaller groups along coastal waters. They escape danger by diving and swimming underwater close to shore using their legs and wings for propulsion.
Conservation Status
Neither buffleheads nor Harlequins are globally threatened. Their populations declined in the early 20th century due to overhunting and habitat loss, but have rebounded thanks to conservation efforts. However, oil spills and other contaminants remain a threat, especially to Harlequins that winter along coastlines. Both species may also be impacted by disturbance, such as low-flying aircraft or boats near their breeding habitats.
Conservation Status
Species | IUCN Status |
---|---|
Bufflehead | Least Concern |
Harlequin Duck | Least Concern |
Conclusion
In summary, buffleheads and Harlequin ducks have distinct appearances and habitat preferences that aid identification. While they share some breeding and feeding behaviors as diving ducks, their nesting locations, sociality, and migratory patterns differ. Both species play important ecological roles and face similar conservation threats. Understanding the comparisons and contrasts between these fascinating sea ducks provides greater insight into their diversity and adaptations.