Aythya fuligula
tufted duck

Aythya fuligula (tufted ducks) is a migratory species. Aythya fuligula has a broad geographic range that extends from Eurasia and Africa to the North American coasts. Aythya fuligula was historically native only to the Palearctic Region. However, over the past century its range has expanded due to an increased availability of open water due to man-made changes in its habitat. Man-made lakes have provided these birds with ideal feeding habitats.

During breeding months (May to early August), A. fuligula inhabits most Palearctic regions such as the Faroe Islands, the British Isles, Norway, nearly all of Europe, and Asia to eastern Siberia. Its limit extends from about 70 degrees North and South latitudes to about 50 degrees north. During the winter months (November to April), tufted ducks can be found in southern Europe, northern Africa, southern Asia, and some areas throughout North America. Aythya fuligula can also be found occasionally throughout areas of Madeira, Borneo, Liberia, the Seychelle, Pelew, Marianne and Philippine Islands. (Bent, 1951; BirdLife International, 2011)

The habitat of A. fuligula varies seasonally due to its migratory behavior. Throughout the breeding season tufted ducks are most often found in shallow lakes. They prefer shallow water ranging from 3 to 5 m deep, with tall thick wetland vegetation, such as reeds, for perching and preening. Vegetation is also an important factor in protection from the wind. During the breeding season A. fuligula typically avoids lakes that are deeper than 15 m.

During winter months A. fuligula can be found generally in larger bodies of open water such as marshes, lakes, estuaries, and man-made ponds. During periods of migration this species can also be found in and along rivers. (Bent, 1951; BirdLife International, 2009)

Tufted ducks are small to medium sized diving ducks. Sexual dimorphism is clearly apparent among males and females. Males are typically larger than females, with an average body length of 42 to 48 cm and a mass of 753.0 to 1026.2 g. Females generally range from 39 to 44 cm in length and weigh in at 629.8 to 906.8 g. Seasonally, body mass will fluctuate between sexes. Both male and female tufted ducks have an average wingspan of 70 cm.

The defining characteristic of this species that separates A. fuligula from the rest of Family Anatidae (ducks, geese, swan) is the distinct tuft located on the back of the head. In males the tuft is black and more prominent, whereas on females it is generally brown and less noticeable. Adult males are solid black with white underbellies and flanks with bright yellow eyes and a distinct tuft that is sometimes matted down from diving. Adult females are brown with dark yellow flanks and a white underbelly and a less pronounced tuft, or sometimes no tuft at all. Females also have bright yellow eyes. The wing undersides of both adult females and males is white.

Juvenile tufted ducks are similar in appearance to mature female adults, however, juvenile color is less vibrant and the tuft is less pronounced. Males in non-breeding plumage also resemble females with a brown tint and a less prominent tuft or no tuft at all. (Cleeves, 2002; Dick, 2002; Robinson, 2005)

Aythya fuligula is monogamous and breeds annually. Adults form pair bonds during spring migration and mates remain together until late June to early July. Reproductive behavior and mannerisms in A. fuligula are similar to other diving ducks. Examples of "showing off" behavior include dipping, also known as drinking, which is when the males and females swim quickly alongside one another and dip their bills in and out of the water. Another example is the neck stretch, which is when the male swims rapidly past the female and reaches its neck to its entire length, holding it there for a few seconds.

Although few, there are some male only displays which consist of nod swimming (a fast swim that includes nodding the head back in forth with full extension), a head throw (similar to neck stretch), and preening behind the wing. (Bent, 1951; Cleeves, 2002; Robinson, 2005)

The breeding season for tufted ducks occurs from May through early August, with peak activity from mid-May to mid-July. The breeding season begins with pair bondings which are formed during spring migration and continue until late June or early July.

For nest site selection, pairs browse along the open waters of wetlands. Females swim into flooded areas looking for a subtle nesting site while males stay alert for predators and other threats. Ideal nesting areas are near water, generally amid dense vegetation. The female is the constructor of the nest which requires almost a week to complete. Grasses and feathers are used as support for the nest. By the third day of nest building, a bowl shape has been formed; by day six, the nest is strong with a defined shape.

Female tufted ducks lay between 6 and 14 eggs a season, but on average between 8 and 10. Eggs are smooth and ovular in shape and range in color from olive-brown to olive-gray. Incubation starts after the clutch is completed and begins on the first night the female remains in the nest overnight. Incubation usually lasts 26 to 27 days. Chicks hatch usually weighing 28 to 31 g, covered in downy feathers, and can generally begin following parents and feeding themselves soon after hatching. Fledging occurs 49 to 56 days after hatching and independence occurs 21 to 56 days after fledging. Reproductive maturity is quickly reached by both sexes, and breeding can occur during the following breeding season. (Bent, 1951; Cleeves, 2002; Robinson, 2005)

Parental care for ducklings is exhibited only by females. Males do contribute indirectly by taking care of nutritional needs of the female during the laying process. The young emerge from the egg without any help from the mother, after which she disposes of the egg by ingesting it, removing it from nest area, or crushing the shells. Aythya fuligula young do not depend on their mothers for food after they learn to dive. This typically occurs within the first 48 hours of hatching, however, during this first week young ducklings rely mostly on surface foods. (Bent, 1951)

Little is known about the lifespan and longevity of tufted ducks.

Aythya fuligula is a migratory species that travels seasonally between the breeding and overwintering grounds. As like most ducks, this species is highly aquatic and rarely strays far from a body of water. It is diurnal for most of it's life but may migrate nocturnally.

During the breeding season, Aythya fuligula males establish territories surrounding their nest and will defend it against neighboring males and predators. During migratory periods and the non-breeding season, A. fuligula is a social species. Groups typically gather in shallow lakes, ponds, and slow moving rivers. Males of A. fuligula are generally silent except during mating. Females make a "karr" sound during flight.

This species can be distinguished from other diving ducks by their unique diving behavior. They launch themselves slightly out of the water to help submerge their bodies underwater while foraging in shallow water. Submergence time for juveniles is less than that of adults. Ducklings and juveniles skim the surface of waters for emerging insects and dive in very shallow water for New Zealand mud snails (Potammopyrgus jenkinsi) and Zebra mussels (Dreissena polymorpha). Submergence time gradually increases as individuals mature and increase in size. (Cleeves, 2002; Hill, 1983)

The range of A. fuligula for both breeding and residency is estimated at 20,400,000 km². Specific territory sizes for male tufted ducks is currently unknown. (BirdLife International, 2009)

The use of visual and acoustic perceptions is key for A. fuligula because it is what they use to communicate for mating rituals and warning calls. Like most birds, A. fuligula perceives its environment through visual, auditory, tactile and chemical stimuli.

Both females and males of A. fuligula make similar calls, korr,korr,korr, or ka-ka-ka, karr, with the female normally presenting the call louder. Calls are normally emitted when beginning to fly, quarreling, or when startled.

In selecting for a mate, two or three male ducks will flaunt their attributes in the presence of a female. To attract mates, A. fuligula males will swim circles around a female, while passing the female rapidly. The male will extend his neck to full length and raises his bill but will not look in the female's direction. Aythya fuligula males, like other diving ducks, A. collaris, also dip their bills frequently and sound calls during courtship. Female A. fuligula have also been spotted flaunting their attributes towards males before mating. (Bent, 1951)

Aythya fuligula is omnivorous. Its main sources of food are molluscs (Mollusca). The most preyed upon molluscs are zebra mussels (Dreissena polymorpha). Zebra mussels are generally very abundant in slow moving rivers, canals, docks, reservoirs, and large areas of freshwater. In addition, tufted ducks consume a variety of plant materials, mostly leaves, stems, and roots. They also occasionally feed on seeds.

There are always quantities of sand, fine shells, and small stones found within tufted ducks' stomachs. This species usually consumes food underwater; however, when a larger vertebrate or plant is being consumed they bring that food to the surface where they crush the food with their bills before ingested.

When foraging, A. fuligula generally forages and feeds with other members of this species. They typically dive together, or one after the other very quickly, and stay submerged from a few seconds to one minute. (Bent, 1951; Olney, 1963)

The main predators of A. fuligula are humans. Aythya fuligula is protected by hunting laws during the breeding season (May through early August); however, they may be hunted during the rest of the year. They can also be hunted by large birds of prey such as hawks, as well as terrestrial predators including foxes, raccoons, and common snapping turtles. In addition, many animals prey on A. fuligula eggs, including domestic dogs, crows, and skunks. Like many birds, female tufted ducks exhibit cryptic coloration to camouflage themselves while incubating the clutch. (Bent, 1951; Cleeves, 2002)

Adult tufted ducks, eggs, and young are all common sources of food for many predators. In addition, they serve as hosts to a species of avian nasal parasite. This parasite is found in mollusks as an intermediate host, and then are consumed by tufted ducks.

Tufted ducks are both herbivores and predators of many aquatic invertebrates. They generally have a significant impact on these populations. (Bent, 1951; BirdLife International, 2011; Cleeves, 2002; Olney, 1963; Rudolfova, et al., 2002)

Aythya fuligula are economically important for the hunting and game industry. The only time when the species cannot be hunted is during breeding season.

Preservation of wetlands is of great economic importance to humans. This could be said to be indirectly brought about by the protection of tufted ducks and other species found in wetland habitats. (Miller and Spoolman, 2008)

There are no known adverse effects of Aythya fuligula on humans.

Aythya fuligula has a very large geographic range and is not declining or fluctuating in population size. The conservation status of tufted ducks on the International Union for Conservation of Nature and Natural Resources' (IUCN) Red list is of least concern. The largest threat to tufted ducks is habitat loss through human induced alteration. This includes destruction of wetlands for human development, waste pollution, and oil spills. (BirdLife International, 2009; BirdLife International, 2011)