Bristol Waterfowl 7: Meller's Duck

Meller's Duck

 On view in a couple of Bristol’s aviaries are pairs of one of the rarest ducks in the world, the Endangered Meller’s duck, Anas melleri. Originating from Madagascar, where it lives in wetlands in the east of the country and the central plateau, Meller’s ducks superficially resemble a large female mallard, with both the male and female having almost the same plumage. There are several species of ducks, especially in the tropics, which do not have the widely variant plumages familiar from temperate zone species, and this is reflected in their breeding behaviour.

The natural habitat of Meller’s duck is freshwater wetlands, especially Lac Alaotra, with rainforest streams and backwaters being important breeding areas. The deforestation in Madagascar, combined with extensive hunting, has caused a rapid decline, and today the world population is probably well under 5,000 individuals. There was a small introduced population on Mauritius, but this is probably now extinct for the same reason. Although they congregate outside the breeding season, when breeding they are highly territorial, and must be housed separately from other waterfowl in captivity. The diet of Meller's duck is typical for a surface-feeding bird – water plants, seeds, and aquatic invertebrates are the main components.

Although the male does not incubate, he is very protective of the female and his territory, and when the 8-10 eggs hatch he will help guard the ducklings, which are very similar to those of a mallard. Especially if the pair is successful the pair bond may last several breeding seasons, although as with many species it might be more accurate to say that both partners remain in the same breeding territory – anthropomorphism in this kind of long-term pairing is a permanent feature of reporting on apparently monogamous species. The young fledge at around 11 weeks, and can breed the following year. The lifespan is around 10-15 years in captivity, much less in the wild.

Unfortunately, because Meller’s duck is not particularly colourful, there has been comparatively interest in collections holding them. They will mingle happily with non-waterfowl species, but will attack and even kill other duck species in their enclosure. The ducklings are not hard to rear, and can be parent-reared fairly readily, but should be removed on fledging. They are slightly susceptible to Duck Virus Enteritis (DVE), so need isolation from wild birds in covered aviaries or annual vaccinations.

As one of the only three surviving species of endemic waterfowl on Madagascar, the others being the Bernier’s teal and Madagascar Pochard, Meller’s ducks should have a higher profile than they currently do. The current captive population on ISIS numbers only 124, with Louisville zoo being the only US collection to hold them. They are sometimes held in mixed exhibits – the Masaola rainforest exhibit at Zurich zoo has them with lemurs – but much might depend on the other species. It would be an interesting experiment to have them in a suitable-sized enclosure though.

Next week is the last in this series, a duck with its stronghold in Iraq, the Marbled teal.

(Images from mangoverde.com, DWCT)