Harlequin ducks ( Histrionicus histrionicus ) are small, colourful sea ducks that winter in coastal areas and migrate inland during the summer to nest along mountain streams. Harlequins are known to nest in Banff and other mountain parks and may be seen on fast moving water or upper elevation lakes from late April to September.
Harlequins are small ducks with rounded heads, stubby bills, and short stocky bodies. The drakes (males) have a striking plumage of dark blue, rust, and bold white streaks. The hens (females) are much more discrete; their subtle brown colour camouflages them for nesting. Hens can be distinguished from other female ducks by three white patches on each side of their face. Juveniles look similar to adult females.
The birds' Latin name, Histrionicus, means a stage player or actor. The birds certainly look and play the part, as the males vigorously defend their mates with head bobbing displays. Harlequins work rapids and rough surf like expert boatmen, using their large, powerful feet to propel their buoyant bodies through the turbulent water. When moving upstream they often clamber over boulders to detour rapids. They tuck into eddies behind boulders to rest before diving to the bottom. Harlequins are swift flyers and, like American dippers, their flight path may be indirect as they follow the exact course of the river, barely above the surface.
Freshwater invertebrates such as the larvae of blackflies, stoneflies, caddisflies, and mayflies are the favoured prey in mountain rivers. Fish eggs are also consumed when available. At their coastal home they use their stubby bill to pry invertebrates such as snails, limpets, crabs, chitons, and mussels from the rocks during the winter months. In the late winter months they feed on herring spawn in large congregations.
Harlequin Duck Nesting Habitat
The harlequin is the only North American duck that migrates inland to nest along turbulent mountain streams. They favour areas of low human disturbance, where the waters are clear and clean.
The nesting habits of the harlequin duck are a well kept secret. They are experts at hiding the nest among low vegetation, stumps, logs, woody debris, or river boulders; occasionally open gravel bars or a cliff face above the rushing water may be used. The nest may be located as much as 50 metres from water's edge. The hen chooses the nest site, and after the eggs are laid the male promptly abandons her and returns to the coast. The hen lays 5 - 7 creamy buff eggs and incubates them for 28 - 30 days.
Harlequin Duck Marine Habitat
For most of the year, Pacific harlequin ducks inhabit exposed rocky sea coasts from Alaska to Oregon. Harlequin ducks that breed in Banff National Park and other areas of the eastern slopes of the Rockies winter in the Strait of Georgia in British Columbia. They congregate around points, reefs and islands to feed on the rich underwater marine life.
Status and Human Threats
Harlequin ducks occur in two separate populations: on both the Pacific and Atlantic Oceans. They inhabit eastern Asia, North America, Greenland, and Iceland. In North America, the Pacific population probably numbers over 200,000 while in the Atlantic there are less than 2,000 harlequin ducks remaining.
The latter population has declined significantly over the last century and is now designated as an endangered species in eastern Canada. The harlequin duck is yellow-listed in Alberta and British Columbia, reflecting the growing concern over declining populations and human impacts. Population declines have been attributed to overhunting, oil pollution, recreational activities, and loss of nesting habitat to hydro-electric projects, road construction, logging, mining, and degradation of riparian areas.
Why Protect Harlequin Ducks?
Globally, harlequin ducks are an integral part of the natural ecosystem and are indicators of pristine environments. Preserving mountainous and coastal environments for harlequin ducks will benefit numerous other species which are also dependent on these areas.
Any information on the ecology of Pacific harlequin ducks may also aid recovery efforts in eastern Canada, and may help avoid further declines in the western population. Researchers throughout western North America are joining forces to learn more about the habits and habitats of these unique birds, with the end goal of protecting them throughout their summer and winter ranges.
Viewing the Harlies
Harlequin ducks are exciting and often entertaining to watch, but they must not be disturbed. Please take care when watching them. Don't venture close to them and keep noise and movement to a minimum.
Harlequin Duck Banding
Since May, 1995, wardens, with the assistance of the Canadian Wildlife Service and local volunteers, have banded a total of 83 harlequin ducks on the Bow River near Lake Louise. Each duck was fitted with a uniquely numbered red plastic band on the left leg and the standard international numbered aluminum band on the right leg. Subsequent sightings of banded birds will help researchers to gather population and habitat use data. In May, 1996, a cooperative project was undertaken in Kananaskis Country east of Banff park. A total of 31 birds were banded then.
These banding projects are part of an international program throughout western Canada and the United States, whereby researchers are cooperating to gain knowledge of the habits and habitats of these unique birds, with the end goal of protecting them throughout their summer and winter ranges.
Our records show that harlequin ducks are found throughout Banff National Park, but the Bow River appears to be particularly important as a staging and breeding area. The stretch between Lake Louise and Castle Junction has one of the highest concentrations on a Spring range in western North America. Many of these birds nest in the park, but some likely travel farther east to the rivers and streams of the foothills.
Already we have sighted birds that were banded since 1993 in the Strait of Georgia near Campbell River, British Columbia, and Port Townsend, Washington. This is helping us to track where our harlequin ducks spend time when they're not in the park. Gathering sightings of banded birds throughout Banff National Park and the eastern slopes is a critical part of our study.