Common shelduck

Tadorna tadorna

Bergeend / Brandgans / Tadorne de Belon

The Common shelduck is a waterfowl species shelduck genus Tadorna. It is widespread and common in Eurasia, mainly breeding in temperate and wintering in subtropical regions; in winter, it can also be found in the Maghreb. Its scientific name comes from Celtic roots and means "pied waterfowl", essentially the same as the English "shelduck".

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be increasing, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern (IUCN, 2012).

The global population is estimated to number c.580,000-710,000 individuals (Wetlands International 2006), while national population sizes have been estimated at c.100-10,000 breeding pairs and c.50-1,000 wintering individuals in China and c.1,000 wintering individuals in Korea (Brazil 2009).

The species is threatened by habitat loss as a result of tidal barrage schemes in Europe (Kear 2005a, Burton 2006). It also suffers predation from American mink Neovison visonon islands (Nordstrom et al. 2002) and is susceptible to avian influenza so may be threatened by future outbreaks of the virus (Melville and Shortridge 2006). The species is hunted for commercial and recreational purposes in Iran (Balmaki and Barati 2006), and its eggs used to be (and possibly still are) harvested in Iceland (Gudmundsson 1979).

Above: adult pair of Common shelducks, female in front

Above: adult male Common shelduck

Above: adult male Common shelduck

Above: adult male Common shelduck, breeding plumage

Above: adult Common shelducks, female in front

Above: Common shelduck duckling, several days old

Above: juvenile Common shelduck