Marbled duck  (Marmaronetta angustirostris)

The marbled duck is classified as Vulnerable on the IUCN Red List (1) and is listed on Appendices I and II of the Convention on Migratory Species (CMS or Bonn Convention) (3). It is also listed on Appendix II of the Bern Convention on the Conservation of European Wildlife and Natural Habitats (4), Annex I of the EC Birds Directive (5) and Annex II of the African-Eurasian Migratory Waterbird Agreement (AEWA) (6).

An elegant bird, the marbled duck suits its name, having a brown body speckled with cream. Its dark eye-patch blends into a broad stripe from the eye to the nape, including a slight crest on the back of the head. With its low, slow flight and noticeably long neck and wings, this duck is easily identifiable in flight. Displaying males give a squeaking ‘jeep’, but this species is otherwise quiet (2).

Perhaps surprisingly, the marbled duck is more closely related to the diving pochards than to the teals and other dabbling ducks that it resembles, and it is almost an intermediate between the two (7).

There are three distinct populations of marbled duck. The first has a fragmented distribution in the western Mediterranean and winters in north and sub-Saharan west Africa. The second breeds in the eastern Mediterranean and winters in Egypt, and the third breeds in western and southern Asia, wintering in Iran, Pakistan and northwest India. A sharp decline has left this species with between 9,000 and 19,000 individuals (2).

Preferring brackish waters, the marbled teal is found on temporary wetlands with plenty of new vegetation (2).

Before moving from the wintering grounds to the breeding grounds, pairs form strong seasonal pair bonds that lasting until incubation. The female incubates between 4 and 12 eggs, from late April through to early July, in a shallow depression concealed by reeds, and lined with grass and down, but at this time the male deserts the female. After 25 to 27 days the eggs hatch, and the hatchlings are cared for by the female until they fledge 55 days later. Outside the breeding season, marbled ducks form small groups and sometimes larger flocks (8).

Marbled ducks feed on small seeds and aquatic invertebrates, dabbling and filtering mud during the early morning and evening, but resting during the day. Population size fluctuates in response to annual differences in rainfall, and individuals will disperse widely to find suitable habitat (2).

Over half of the marbled duck’s habitat was destroyed during the 20^thcentury when wetlands across its range were drained for agriculture. Breeding sites were degraded in Tunisia, Turkey, Morocco and Spain during hydrological work that resulted in reed cutting and burning. Pollution from agricultural, industrial and domestic sources is also a threat, and the species is at risk from lead poisoning. When breeding, marbled ducks are targeted by hunters and egg collectors (2).

The marbled duck is protected by law in many countries throughout its range. Conservation action has targeted this species in Spain, and surveys have been carried out in Morocco and Turkey. A European Action Plan was published in 1996 and updated in 2008, and proposes regular population monitoring, research into the species’ ecology, protection of all habitats regularly home to it, prevention of mortality, and increased public awareness (2) (9).

View information on this species at the UNEP World Conservation Monitoring Centre.

For further information on the marbled duck see:

• Iñigo, A., Barov, B., Orhun, C. and Gallo-Orsi, U. (2008) Species Action Plan for the Marbled Teal Marmaronetta angustirostris in the European Union. BirdLife International, Cambridge, UK. Available at:
  http://ec.europa.eu/environment/nature/conservation/wildbirds/action_plans/docs/marmaronetta_angustirostris.pdf
• BirdLife International. (2001) Threatened Birds of Asia: the BirdLife International Red Data Book. BirdLife International, Cambridge, UK. Available at:
  http://birdbase.hokkaido-ies.go.jp/rdb/rdb_en/marmangu.pdf
• Kear, J. (2005) Ducks, Geese and Swans. Oxford University Press, Oxford, UK.