Fuegian Steamer Duck, Tachyeres pteneres

The Fuegian Steamer Duck (Tachyeres pteneres) known also as the Magellanic Flightless Steamer Duck, is a flightless duck located in South America. It belongs to the steamer duck genus Tachyeres. It inhabits the rocky coasts and coastal islands from southern Chile and Chiloe to Tierra del Fuego, switching to the adjacent sheltered lakes and bays further inland while breeding.

It is a huge waterfowl measuring at 7.7 to 15 pounds and 26 to 33 inches with the males noticeably larger than the females. The wingspan measures around 33 to 43 inches. This species of duck outweighs any other wild species called “duck”, although this species is only distantly related to most true ducks. In the males, the head and the neck is a blue grey, with paler coloration crown and forehead. It has a narrow white colored eye-ring which continuing backwards as a stripe and a reddish brown colored throat. The abdomen, ventral area and under tail coverts are white and the tail is a grey color. The females are a darker gray brown on the head and a dark reddish color on the throat. The body and the wings of the female look much like the males but she may have brown or wine coloring on the feathers. The juvenile individual is much like the female but slightly duller in coloration.

It either nests near water obscured by dense and shrubby vegetation or in abandoned penguin nest burrows in September through December. The clutch consists of about 4 to 11 eggs, averaging at about 9. The eggs are ivory colored and measure 3.2 x 2.2 inches and weigh around 5.9 ounces. The incubation period lasts for 28 to 40 days and the young fledge at 120 to 130 days and are then driven from the parent’s territory by the parents to form flocks with other ousted immature steamer ducks. They achieve sexual maturity at two to three years of age. The adult males are known to be extremely aggressive during the mating season, including towards other waterfowl, but might join mixed species winter flocks without incident.

There are a handful of potential predators of the eggs and the young birds including foxes, caracaras, gulls, skuas, and giant petrels. The healthy adults probably have no natural predators. It lives principally off of saltwater mollusks, crustaceans, and fish of small size. During the breeding season, they show a tendency to consume and feed their young small snails, insect larvae, isopods and amphipods.

It is locally famous for the aggressive disposition of the adult males. Some incidents have allegedly occurred where a raging male was placed by a misguided collector among adults of various other waterfowl species and killed all the other birds with their powerful spurred wings.

Image Caption: Two Magellanic Flightless Steamer Duck Tachyeres pteneres in Cologne Zoo. Credit: Sarefo/Wikipedia (CC BY-SA 3.0)