Geographic Range
        Harlequin ducks breed in Alaska and Yukon, south to Wyoming, California, and Massachusetts,
            from southern Baffin Island and Quebec south to Labrador and the Gaspe Peninsula.
            They also breed in Greenland and Iceland. They winter along the coasts of the Bering
            Sea Islands, Japan, Korea, China, California, and from southern Labrador to Long Island.
        
- Biogeographic Regions
 - nearctic
 - palearctic
 - oceanic islands
 
- Other Geographic Terms
 - holarctic
 
Habitat
        Harlequin ducks live along fast flowing streams and rivers in rocky terrain with plenty
            of vegetation, such as trees, during breeding season in the summer. The offspring
            cannot be seen very well in this type of terrain. During summer they can be found
            as high as 3352 meters above sea level. In wintering locations they feed and rest
            in shallow shore waters, along rocky coastlines.
        
- Habitat Regions
 - temperate
 - polar
 - terrestrial
 - saltwater or marine
 - freshwater
 
- Aquatic Biomes
 - rivers and streams
 - coastal
 
- Other Habitat Features
 - riparian
 
Physical Description
        Harlequin ducks are between 35.6 and 50.8 centimeters and weigh 0.45 to 0.68 kilograms.
            Males have blue-grey bodies with chestnut flanks and distinctive white patches on
            the head and body. These white patches are outlined with black. In flight males show
            white on their wings with a metallic blue speculum. Females are dusky brown with two
            or three whitish patches on the sides of the face. Females do not have any white on
            their wings in flight and do not have a speculum. However, when this species molts
            it is hard to distinguish between males and females.
        
- Other Physical Features
 - endothermic
 - homoiothermic
 - bilateral symmetry
 
- Sexual Dimorphism
 - sexes colored or patterned differently
 - male more colorful
 
Reproduction
        When a female is looking for a mate, one characteristic that is looked for is bright
            plumage, indicating sexual selection in this sexually dichromatic species. Nice plumage
            is seen as a sign of good health. A female duck wants to choose a mate that will be
            able to protect her from other males during the mating season. Plumage of males is
            affected by age and the time of their last molt. Males also perform courtship dances
            to attract females. They will often shake their heads and tails while making a whistling
            noise when they are around females. They may also make short, ritualistic flights
            close to the water surface.
        
- Mating System
 - monogamous
 
        Harlequin ducks choose their mates beginning around October. Breeding begins in May
            and June. Harlequin ducks are seasonally monogamous, with pairs forming for a single
            breeding season. Females lay from 5 to 8 eggs, which hatch after 27 to 29 days. Young
            fledge and become independent by 70 days old. Breeding success for both males and
            females remains low until the age of 5, even though they become sexually mature at
            around 2 years old.
        
- Key Reproductive Features
 - iteroparous
 - seasonal breeding
 - gonochoric/gonochoristic/dioecious (sexes separate)
 - sexual
 - oviparous
 
        Females invest heavily in raising their offspring. Males participate in nest building.
            Once a female begins to incubate the eggs, the male leaves and migrates back to the
            ocean to undergo the annual molt. Females incubate eggs with her down feathers and
            through the development of a brood patch, where she loses feathers. This way, not
            only are the down feathers heating the eggs, but when she is on the nest her bare
            skin will be directly on the eggs transferring her body heat efficiently. The brood
            patch actually fills with fluid to help incubate the eggs. Once the eggs hatch, the
            female takes her hatchlings to the water within a few days of hatching and teaches
            them how to catch and find their own food. Approximately 45 days later the offspring
            begin to fly. Females continue to protect their young until it is time for both the
            mother and the offspring to migrate back to coastlines. Sometimes there is post-independence
            association with the parents because these ducks often migrate to the same area yearly.
        
- Parental Investment
 - precocial
 - 
         
          pre-fertilization
         
         
- provisioning
 - 
           
            protecting
           
           
- female
 
 
 - 
         
          pre-hatching/birth
         
         
- 
           
            provisioning
           
           
- female
 
 - 
           
            protecting
           
           
- male
 - female
 
 
 - 
           
            provisioning
           
           
 - 
         
          pre-weaning/fledging
         
         
- 
           
            provisioning
           
           
- female
 
 - 
           
            protecting
           
           
- female
 
 
 - 
           
            provisioning
           
           
 - 
         
          pre-independence
         
         
- 
           
            provisioning
           
           
- female
 
 - 
           
            protecting
           
           
- female
 
 
 - 
           
            provisioning
           
           
 - post-independence association with parents
 
Lifespan/Longevity
        Lifespan of harlequin ducks normally ranges from 12 to 14 years in the wild. There
            is no information on the lifespan of harlequin ducks in captivity.
        
Behavior
        Harlequin ducks migrate in spring from coastlines to inland areas. They start to migrate
            from the east coast of North America during April to mid-May and from the west coast
            of North America during late March. They are not seen in large concentrations and
            move short to intermediate migration distances. Immature or injured ducks remain on
            wintering grounds. In the fall males undergo molt migration that begins around late
            June. Molt migration is when males leave females during incubation and return to the
            coast to undergo their yearly molt.
        
- Key Behaviors
 - flies
 - natatorial
 - diurnal
 - motile
 - migratory
 - social
 
Home Range
        The home range of harlequin ducks is relatively small, both during the breeding season
            and winter. They are seen in small groups both migrating and in their home range.
        
Communication and Perception
        Harlequin ducks communicate mainly with vocalizations. Males also perform courtship
            dances to attract females.
        
Food Habits
        Harlequin ducks eat primarily an animal diet of invertebrates and some fish. They
            have been reported eating crustaceans, mollusks, insects, and small fish. Harlequin
            ducks dive for their food but also dip their heads in shallow water to obtain food.
        
- Animal Foods
 - fish
 - eggs
 - insects
 - mollusks
 - aquatic crustaceans
 
Predation
        Harlequin duck females and immature individuals are cryptically colored to protect
            them from predators. They are also vigilant and will swim or fly to escape threats.
            Reported predators include bald eagles, jaegers, ravens, and river otters on adults,
            and mink, martens, foxes, and wolves on nests.
        
- Anti-predator Adaptations
 - cryptic
 
Ecosystem Roles
        Harlequin ducks are important members of the ecosystems they inhabit. They are parasitized
            by lice and ticks.
        
- Ecosystem Impact
 - creates habitat
 
- lice ( Mallophaga )
 - ticks ( Acari )
 
Economic Importance for Humans: Positive
        
         Ducks
        
        in general have always been important to humans. Many types of ducks are hunted and
            consumed by cultures around the world. As a game animal, harlequin ducks have an economic
            importance to the duck hunting industry.
        
- Positive Impacts
 - food
 - research and education
 
Economic Importance for Humans: Negative
There is no evidence suggesting that harlequin ducks have a negative impact on humans.
Conservation Status
        Harlequin ducks are not endangered currently. At one point they were considered threatened
            on the Atlantic coastline. These ducks are susceptible to oil spills, since they spend
            most of their time in the water, and high mortality has resulted from previous oil
            spills. For example, Alaskan harlequin ducks were still exhibiting reduced survival
            rates as a result of the 1989 Exxon Valdez oil spill as late as 1998. Logging is a
            significant threat in the state of Washington because it removes suitable forests
            along the streams that these ducks use during the breeding season. Also, logging causes
            silt build up in streams, reducing the amount of prey available.
        
Other Comments
        In the northeast this species has the nickname "The Lords and Ladies".
        
Additional Links
Contributors
Alex Riley (author), Centre College, Matthew Johnson (author), Centre College, Alex Riley (author), Centre College, Matthew Johnson (author), Centre College, Stephanie Fabritius (editor, instructor), Centre College, Tanya Dewey (editor), Animal Diversity Web.
- Nearctic
 - 
          
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
           
- native range
 - 
          
the area in which the animal is naturally found, the region in which it is endemic.
 
- Palearctic
 - 
          
living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.
           
- introduced
 - 
          
referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.
 
- oceanic islands
 - 
          
islands that are not part of continental shelf areas, they are not, and have never been, connected to a continental land mass, most typically these are volcanic islands.
 
- introduced
 - 
          
referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.
 
- holarctic
 - 
          
a distribution that more or less circles the Arctic, so occurring in both the Nearctic and Palearctic biogeographic regions.
          Found in northern North America and northern Europe or Asia.
 
- temperate
 - 
          
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
 
- polar
 - 
          
the regions of the earth that surround the north and south poles, from the north pole to 60 degrees north and from the south pole to 60 degrees south.
 
- terrestrial
 - 
          
Living on the ground.
 
- saltwater or marine
 - 
          
mainly lives in oceans, seas, or other bodies of salt water.
 
- freshwater
 - 
          
mainly lives in water that is not salty.
 
- tundra
 - 
          
A terrestrial biome with low, shrubby or mat-like vegetation found at extremely high latitudes or elevations, near the limit of plant growth. Soils usually subject to permafrost. Plant diversity is typically low and the growing season is short.
 
- forest
 - 
          
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
 
- coastal
 - 
          
the nearshore aquatic habitats near a coast, or shoreline.
 
- riparian
 - 
          
Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).
 
- endothermic
 - 
          
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
 
- bilateral symmetry
 - 
          
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
 
- monogamous
 - 
          
Having one mate at a time.
 
- iteroparous
 - 
          
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
 
- seasonal breeding
 - 
          
breeding is confined to a particular season
 
- sexual
 - 
          
reproduction that includes combining the genetic contribution of two individuals, a male and a female
 
- oviparous
 - 
          
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
 
- young precocial
 - 
          
young are relatively well-developed when born
 
- natatorial
 - 
          
specialized for swimming
 
- diurnal
 - 
          
- active during the day, 2. lasting for one day.
 
 
- motile
 - 
          
having the capacity to move from one place to another.
 
- migratory
 - 
          
makes seasonal movements between breeding and wintering grounds
 
- social
 - 
          
associates with others of its species; forms social groups.
 
- visual
 - 
          
uses sight to communicate
 
- acoustic
 - 
          
uses sound to communicate
 
- cryptic
 - 
          
having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.
 
- food
 - 
          
A substance that provides both nutrients and energy to a living thing.
 
- carnivore
 - 
          
an animal that mainly eats meat
 
- piscivore
 - 
          
an animal that mainly eats fish
 
- visual
 - 
          
uses sight to communicate
 
- tactile
 - 
          
uses touch to communicate
 
- acoustic
 - 
          
uses sound to communicate
 
- chemical
 - 
          
uses smells or other chemicals to communicate
 
References
Adams, P., G. Robertson, I. Jones. 2000. Time-Activity Budgets of Harlequin Ducks Molting in the Gannet Islands, Labrador. The Condor , 102/3: 703-708. Accessed March 15, 2009 at http://www.jstor.org/sici?sici=0010-5422(200008)102%3A3%3C703%3ATBOHDM%3E2.0.CO%3B2-G .
Alderfer, J. 2006. Complete Birds of North America . Washington, D.C.: National Geographic Society.
Ehrlich, P., D. Dobkin, D. Wheye. 1988. The Birder's Handbook- A Field Guide to the Natural History of North American Birds . New York: Simon & Schuster Inc..
Elphick, C., J. Dunning Jr., D. Sibley. 2001. The Sibley Guide to Bird Life & Behavior . New York: Alfred A. Knopf.
John, B., F. John. 1994. National Audubon Society Field Guide to North American Birds . New York: Chanticleer Press, Inc..
Milton, R., P. MacDonald. 1996. "Department of Natural Resources" (On-line). The Harlequin Duck- Keeping Watch. Accessed May 06, 2009 at http://www.gov.ns.ca/natr/wildlife/conserva/19-04-6.htm .
Reed, J., P. Flint. 2007. Movements and foraging effort of Steller's Eiders and Harlequin Ducks wintering near Dutch Harbor, Alaska. Journal of Field Ornithology , 78/2: 124-132. Accessed March 13, 2009 at http://www3.interscience.wiley.com/journal/117963253/abstract?CRETRY=1&SRETRY=0 .
Robertson, G., F. Cooke, R. Goudie, W. Boyd. 1998. Moult Speed Predicts Pairing Success in Male Harlequin Ducks. Animal Behaviour , 55/6: 1677-1684. Accessed March 12, 2009 at http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6W9W-45RFGWF-X&_user=4678464&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000063948&_version=1&_urlVersion=0&_userid=4678464&md5=a9e1418c68b294c5b92606dec1ca69fd .
T., T. 2001. "Blue Planet Biomes" (On-line). Harlequin Ducks. Accessed March 15, 2009 at http://www.blueplanetbiomes.org/harlequin_duck.htm .
2009. "Alaska SeaLife Center" (On-line). Harlequin Duck. Accessed March 12, 2009 at http://www.alaskasealife.org/New/visitors/index.php?page=Harlequin-duck.php .
Gale Group. 2002. Harlequin Duck. Pp. 365- 389 in Grzimek's Animal Life Encyclopedia , Vol. 8, 2 Edition. MI: Farmington Hills.
2008. "Seattle Audobon Society" (On-line). Harlequin Duck. Accessed March 13, 2009 at http://www.birdweb.org/birdweb/bird_details.aspx?id=83 .