Netta rufina

Geographic Range

Classified as a diving duck species, red-crested pochards ( Netta refina ) have a wide breeding range that extends from the British Isles to China. Almost half of the population (27,000 to 59,000 pairs) breeds in Europe and about 20% (4,200 to 12,000 pairs) breeds in the European Union (EU). Eighty percent of the EU population breeds in Spain, 15% breeds in France, and a small percentage breeds in Germany. As with many other species, red-crested pochard breeding trends vary between countries. There is an eastward range that extends from central EU member states, with the exception of Hungary and Poland. In these areas, the population is in decline. Red-crested pochards stay in Eurasia for the winter months and there are three traditional groups that are seen in the western Palearctic. The Black Sea and Eastern Mediterranean groups, with about 43,500 birds, are in the EU areas and the Central European group takes up most of the member states, containing upwards of 50,000 birds during the winter. In autumn, immature birds and adult males travel together in dense flocks for moulting, which is usually northbound through Western Europe, located in Germany, Spain, Switzerland, and the Netherlands. Along with Western and Central Europe, large flocks have also been seen in Central Asia during this time.

• Biogeographic Regions
• palearctic palearctic
  • native native

Habitat

Red-crested pochards prefer to nest in eutrophic ponds and lakes that are bordered by emergent halophytes and beds of macrophytes. They also nest near slow-current rivers with clearings of open water or islands with shrubs and grasses. Prior to the 1980's, red-crested pochards preferred nesting near brackish water. Since then, nearly the entire breeding population has changed its habitat to freshwater marshes and reed beds, likely as a response to growing populations of yellow-legged gulls and the predators they attract.

During their molting period, red-crested pochards no longer fly. They seek out areas of open water (coastal, inland, brackish, or fresh) with an abundance of charophyte beds. In the winter months, lakes and ponds are used as daytime resting areas and the existing vegetation provides some shelter. Preferred habitats are in open spaces that are free from disturbances and contain accessible feeding sites.

• Habitat Regions
• temperate temperate
• freshwater freshwater

• Terrestrial Biomes
• taiga taiga

• Aquatic Biomes
• lakes and ponds
• rivers and streams

• Wetlands
• marsh marsh

Physical Description

Male red-crested pochards have orange-brown heads with reddish beaks and pale flanks. The less-colorful females are brown with pale-colored cheeks and bicolored bills. Juveniles are darker with multicolored bellies. The basal metabolic rate is about 4.068 W.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry
• polymorphic polymorphic

• Sexual Dimorphism
• male larger
• sexes colored or patterned differently
• male more colorful

Reproduction

Red-crested pochards are monogamous breeders.

• Mating System
• monogamous monogamous

Pairs form in the winter and a bond develops throughout the spring migration. Red-crested pochards breed in isolated pairs or in loose colonies. Many birds begin breeding at one year of age, though others don't begin until year two. Breeding location varies by area; birds in Austria breed in lakes, birds in Belgium breed in ponds, and birds in Denmark breed in lagoons. Females lay their eggs between late March and early July in central and southern Europe. Nests are built from the ground up, mostly in the dense vegetation of reed beds. Nesting among other species such as the black-winged stilt ( Himantopus himantopus ) increases breeding success, and about 30% of nests include egg parasitism.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• fertilization fertilization
• oviparous oviparous

From the time the eggs are laid to the time they hatch, the female red-crested pochard is the primary caretaker. She is responsible for incubating the eggs and looking after the chicks until they fledge approximately 50 days after hatching. The male is responsible for courtship-feeding in which the female approaches him, takes the food from his bill, and feeds the ducklings. The young return to their mother's side voluntarily or when called to receive food.

• Parental Investment
• altricial altricial
• female parental care female parental care
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • female
• pre-independence
  • provisioning
    • female
  • protecting
    • female

Lifespan/Longevity

There are no overall survival or mortality monitoring systems throughout Europe, but separate areas do surveys. Very little has been published about annual survival rates in N. rufina . Duckling and fledgling survivorship, however, has been monitored in Spain and Germany, an average 5.5 to 6.8 ducklings per clutch survive to two weeks old, and an average of 4.3 to 4.4 survive to independence. Little is known about N. rufina longevity and lifespan while in captivity.

Behavior

Red-crested pochards are migratory and disperse locally as well. Breeding occurs from mid-April through July at times in single pairs or loose groups. During this time, male pochards and non-breeders molt and become flightless for around four weeks from June through August. The birds travel to their wintering grounds in October after the molting and breeding seasons are complete. During winter migration, red-crested pochards form large groups with hundreds of other individuals. As a diurnal species, these birds are most active in the morning and in the evening.

• Key Behaviors
• flies
• natatorial natatorial
• diurnal diurnal
• motile motile
• nomadic nomadic
• migratory migratory
• social social

Home Range

Red-crested pochards can be found from the British Isles all the way to China. Territory size is unknown in this species, since it is often on the move and does not always occupy the same areas each year.

Communication and Perception

Not much is known about red-crested pochard communication systems. Sound is important when calling other flocks to a feeding area, smell is important for mating, and touch is important when caring for young. Sight allows birds to see body language, identify others, find food, and care for young.

• Communication Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Red-crested pochards are herbivores. During the breeding season, they feed on aquatic plants and algae (macrophytes and charophytes ). Outside the the breeding season they also eat sedges , tape-grasses , and rice , which helps them adapt to a winter seed diet.

• Primary Diet
• herbivore herbivore
  • granivore granivore
  • algivore

• Plant Foods
• leaves
• seeds, grains, and nuts
• algae

• Other Foods
• fungus

Predation

Humans are the only predator species that affects the population of these birds. Humans affect red-crested pochards in many ways, including habitat loss, hunting, and pollution.

• Anti-predator Adaptations
• cryptic cryptic

Ecosystem Roles

Little information is available on the role of red-crested pochards in the ecosystem. However, this species helps control wetland plant populations and acts as a seed disperser.

• Ecosystem Impact
• creates habitat

Economic Importance for Humans: Positive

Hunting this bird is an economic activity that helps keep populations under control. Specific impacts of the August to September hunting season on breeding populations is unknown.

The down feathers of this species, along with close relatives, are used in jackets, blankets, sleeping bags, and pillows. There is a long relationship between ducks and humans, economically and culturally.

• Positive Impacts
• food food
• body parts are source of valuable material
• ecotourism ecotourism
• research and education

Economic Importance for Humans: Negative

Netta rufina and close relatives have been known to be agricultural pests as well as carriers of avian influenza.

• Negative Impacts
• injures humans
  • causes disease in humans causes disease in humans
• crop pest

Conservation Status

Red-crested pochard populations are subject to lead poisoning from the hunting season: 4 to 36% of the animals tested had lead poisoning from having a lead shot pellet in their gizzards. To get rid of this threat, lead shot should be illegal and people should have to hunt with steel shot. Habitat loss is also one of the more important reasons for population declines. Wetland drainage and climatic changes affect where these birds breed and travel for the winter. Over the decades, red-crested pochards have adapted with the environment fairly quickly and can change their wintering area in response to weather and climate changes. Conservation efforts should focus on minimizing wetland loss, degradation, and pollution. Having better information on this species will also help future researchers improve wild habitats. Red-crested pochards are sensitive to human disturbance, so socio-economic activities should be done minimally so there are no adverse affects.

Other Comments

In order to understand these birds better, research must be done locally and internationally. Their population limits and degree of isolation is not well-known, along with local population sizes in popular breeding areas (including mortality and productivity). Several monitoring plans should be implemented so that better information is available for this species.

Additional Links

Encyclopedia of Life

Contributors

Jessie Lewin (author), University of Wisconsin - Stevens Point, Christopher Yahnke (editor), University of Wisconsin-Stevens Point, Tanya Dewey (editor), University of Michigan-Ann Arbor, Shaina Stewart (editor), University of Wisconsin - Stevens Point.

References

Amat, J. 1991. Effects of red-crested pochard nest parasitsm on mallards. The Wilson Bulletin , 103: 501-503. Accessed August 19, 2013 at http://www.jstor.org.ezproxy.uwsp.edu/stable/pdfplus/4163056.pdf?acceptTC=true .

Butchart, S., J. Ekstrom, L. Malpas. 2013. "Red-Crested Pochard" (On-line). Birdlife International. Accessed August 19, 2013 at http://www.birdlife.org/datazone/speciesfactsheet.php?id=469 .

Defos du Rau, P., C. Barbraud, J. Mondain-Monval. 2003. Estimating breeding population size of the red-crested pochard in the Camargue (southern France) taking into account detection probability: implications for conservation. Animal Conservation , 6: 379-385. Accessed August 19, 2013 at http://onlinelibrary.wiley.com.ezproxy.uwsp.edu/doi/10.1017/S1367943003003457/pdf .

Gay, L., P. Defos Du Rau, J. Mondain-Monval, P. Crochet. 2004. Phylogeography of a gam species: the red-crested pochard and consequences for its management. Molecular Ecology , 13: 1035-1045. Accessed August 19, 2013 at http://web.ebscohost.com.ezproxy.uwsp.edu/chc/pdf?sid=0b914a8a-8c17-4e75-b1ad-28c0a388a05d%40sessionmgr4&vid=2&hid=9 .

Johnsgard, P., J. Kear. 1968. A Review of Parental Carrying of Young by Waterfowl. Papers in Ornithology , 32: 2-16.

2011. "Encyclopedia of Life" (On-line). Accessed August 22, 2013 at http://eol.org/pages/1048530/details .

www.whatbird.com. 2013. "Field Guide to Birds of the United Kingdom" (On-line). Whatbird.com. Accessed August 21, 2013 at http://uk.whatbird.com/obj/1175/behavior/Red-crested_Pochard.aspx .

Natura 2000. Management plan for red-crested pochard. 005-2007. France: European Communities. 2007. Accessed August 19, 2013 at http://ec.europa.eu/environment/nature/conservation/wildbirds/hunting/docs/red_crested.pdf .

Avibirds. 2012. "Profile Red-crested Pochard" (On-line). avibirds.com. Accessed August 21, 2013 at http://www.avibirds.com/euhtml/Red-crested_Pochard.html .