The brown teal (pāteke) is one of three closely related species of teal in New Zealand, the other two being the flightless sub-Antarctic Auckland teal and Campbell Island teal. Once common throughout New Zealand, including Stewart Island and Chatham Island, habitat destruction, especially swamp drainage, and predation by introduced predators as well as hunting have resulted in pāteke becoming one of New Zealand’s most nationally endangered species of waterfowl.
Pāteke are about half the size of the common mallard duck – 48cm and just over half a kilo – the male is slightly larger than the female. They have warm brown plumage, with dark-brown mottling on the breast. Breeding males have a glossy green head, a narrow white collar, broad green and narrow white bands on the wings and a white flank patch. A distinctive feature of all pāteke is their blue-black bill and the narrow white ring around the eye. Males give a soft whistle, and the female a low quack and growl.
They are a member of the subfamily Anatinae, or the ‘dabbling ducks,’ named after the way they take food. Members of this subfamily feed mainly on vegetable matter either by upending to feed off submerged plants or by grazing on the surfaces of freshwater or estuaries. Dabbling ducks are usually strong and willing fliers, but the pāteke is an exception. While it can fly perfectly well, it is reluctant to do so and usually prefers to swim away from danger. Dabbling ducks walk well on land, and some species feed mostly on land rather than in the water, including the pāteke, which regularly feed on the forest floor.
Eighteen captive-bred pāteke were released between 2000 and 2001, with breeding confirmed in 2002 and every year since then. The pāteke have been highly productive, even those pairs found in the forest away from the wetlands, with broods of up to 8 ducklings seen. We don’t know how many pairs are currently present in the sanctuary (at least 10 in 2006) because they are scattered throughout the valley. The population is assumed to be self-sustaining but may need a top-up transfer in future to improve genetic diversity and ensure its long-term survival.