Harteman Wildfowl, presented by Jan Harteman
The marbled duck, or marbled teal, is a medium-sized duck. It used to be included among the dabbling ducks, but is now classed as a diving duck. The scientific name, Marmaronetta angustirostris, comes from the Greek marmaros, marbled and netta, a duck, and Latin angustus, narrow or small and rostris billed.
This species appears to have suffered a rapid population decline, evidenced in its core wintering range, as a result of widespread and extensive habitat destruction. It therefore qualifies as Vulnerable (IUCN, 2012). However, data are scarce and some birds may have relocated to alternative wintering sites. Apparent increases in Iraq and the western Mediterranean population probably reflect improved observer coverage rather than genuine changes. This population has suffered a long-term decline and widespread loss of habitat.
The global population is estimated at c.50,000-55,000 individuals, based on estimates of 3,000-5,000 in the west Mediterranean and West Africa (T. Dodman in litt. 2002); 1,000 in the east Mediterranean; 5,000 in south Asia, and at least 44,000 individuals in south-western Asia.
Over 50% of suitable habitat may have been destroyed during the 20th century. Wetland drainage for agriculture occurs across its range, most significantly in Iraq where the species remains threatened by fluctuating water levels and local water shortages. Hydrological work has severely affected breeding sites in Tunisia, Turkey, Morocco and Spain. In Iraq, the species is also threatened by illegal hunting and persecution, exacerbated by it being the principal wildfowl target for hunters during the summer months (Salim 2010). Reed-cutting, reed-burning and grazing commonly reduce the amount of habitat for nesting. Pollution from agricultural, industrial and domestic sources is a threat at many sites. When breeding, it is vulnerable to shooting and egg collection. Further mortality results from birds caught in fishing nets and lead poisoning (Svanberg et al. 2006, Mateo et al. 2001). A lack of habitat following hot, dry summer months probably results in high juvenile and adult mortality post-breeding (Green 2000, 2007). Lack of water availability for the El Hondo reservoirs in Alicante have led to a major decline in Spain since 1998 (Ballesteros et al. 2008).
It is legally protected in Bulgaria, Israel, Morocco, Spain, Russia, Tunisia and Turkey. Key Biodiversity Area (KBA) project surveys were conducted in Iraq by Nature Iraq during 2005-2010, finding c.44,000 individuals in 2010 and resulting in the proposal of several KBAs which hold wintering and breeding populations to be designated as protected areas (Salim 2010). Awareness-raising efforts were carried out in Iraq including the production of posters and hosting of conferences and meetings with hunters and hunting societies by Nature Iraq (Salim 2010). Conservation programmes have been carried out in Spain. Survey and research projects have been carried out in Morocco and Turkey. An updated European action plan was published in 2008 (Iñigo et al. 2008).
Conduct regular surveys and monitoring. Research its ecology. Protect habitat at all sites regularly holding the species. Prevent mortality from hunting and other causes. Increase public awareness.
More information: http://www.iucnredlist.org/details/22680339/0
By Dan Cowell
Marbled Teal are easy to breed in captivity. The breeding season in the Northern hemisphere begins in May with hens laying about 7 to 14 eggs per clutch that hatch in about 25 days. We can provide the same style of boxes that the dabbling ducks use, although the hens will also make a nest under cover on the ground. Marbled Teal are easy going ducks that do well in mixed collections. They are not very winter hardy, and shelter may need to be provided during the coldest winter nights. I have noticed that they are not very bold ducks, and will be picked on by larger species. They do best when housed with other small tropical ducks. Aviaries do not need to be very large, just provide plenty of cover since these birds are often shy and nervous in captivity. They do love to graze, so give them plenty of greens. I have also noticed that they will come around for a snack of mealworms as well.
Above: adult drake Marbled teal
Above: sub-adult pair Marbled teal
Above: sub-adult Marbled teal
Above: sub-adult Marbled teal
Above: adult pair Marbled teal (female left, drake right)
Above: group of Marbled teals