When you think of ducks you normally think of lakes, marshes and rivers — to consider a duck on the sea is almost like a duck out of water. However, the combined effect of habitat loss and predation has meant that now the only place you will ever really catch sight of our little brown teal is off the coast.
Not only has the drainage of our wetlands and the reclamation of estuaries left the brown teal with little choice but to find another place to live, the fact that at least every second New Zealander wants to live and/or holiday on the seashore does not make the mainland coast a great second option either, which leaves only the offshore islands.
The brown teal or Pateke belongs to the same genus as the mallard, grey duck, grey teal and the shoveler duck and there are also numerous other cousins around the world. But, of all the family members, it is the least able to cope with the changes brought about by settlement and is now considered one of the four rarest waterfowl in the world. The brown teal is closely related to the Australian chestnut teal which visit this country occasionally but have yet to breed in New Zealand.
The Pateke has a small width head with a uniform dark brown face and a fine white ring around the eye. Most of its body is dark brown with pale edges to the feathers although the breast is chestnut. The bill is a bluish black colour while the legs and feet are slate grey. During the breeding season, male ducks on the mainland develop glossy green hats of plumage on the head with distinctive distinguished-looking narrow white collars and conspicuous white patches on their flanks. Island males are a little more circumspect and have opted out of such flashy outfits to win favours of the females.
The males can also be distinguished from the females by their calls as they give soft, high-pitched wheezy whistles, while the softer sex produce low quacks and growls.
Endemic to New Zealand, the brown teal has evolved over the centuries into three subspecies, one on the New Zealand mainland and offshore islands, chlorotis, and the other two on sub-Antarctic islands in the Campbell and Auckland groups, nesiotis, and aucklandica. The latter two species are flightless and, with the introduction of cats to these islands, were virtually eliminated from all but a few predator free islets.
As the mainland Pateke are the most closely related to the Australian chestnut teal, it is thought that they have evolved from a much more recent invasion of the Australian ducks, while the island varieties must have been isolated from their Australian counterparts for many centuries.
Pateke feed on aquatic or marine invertebrates which they scoop off the water surface or mud in shallow water estuaries, freshwater wetlands, in peaty pools and sheltered coastal bays. They may also be seen probing seaweed on the beach or even rummaging through the bush, especially at night, as they are mainly nocturnal feeders.
Brown teal tend to flock at traditional roosting sites when not feeding although, during the breeding season, these flocks are mainly juveniles and non-paired adults.
The mainland species was mainly found from Northland to Stewart Island and the Chathams wherever there were freshwater wetlands. The species is now restricted to the coastal wetlands of Northland, from the Bay of Islands to Tutukaka, and Great Barrier Island, where their preferred habitat is tidal creeks with well-forested banks, although rough pasture is used for foraging. A few Pateke still exist in the lower Waikato and Coromandel areas with some on Little Barrier Island and Great Mercury Islands.
Even in these locations the bird is still not safe as the range is reduced with each passing year. Within the last 30 years they have disappeared from harbours at Hokianga, Waipu and Kaeo-Kerikeri in the far north.
The existence of communal roosting sites has allowed fairly accurate census of the remaining populations and there are estimated to be only 2500 birds remaining in the wild.
As well as loss of habitat, hunting, predation and disease have also played a part in the rapid decline in teal. The bird’s reluctance to fly and its flocking nature made brown teal an easy target for hunters and, even though they have had legal protection since 1921, the killing goes on, as one duck looks much like another.
The usual predators such as cats, rats and stoats probably all had their penny’s worth in the decline of the brown teal and dogs are suspected of playing a part too.
The preservation of the ducks’ habitat is vital for survival but coastal areas are prime real estate and competition for land use is fierce. Public education on the preservation of these habitats and the control of predators is one of the key factors to ensuring the survival of the brown teal.
A spark of hope exists with the raising of birds in captivity and then releasing them into the wild which is being carried out by the Department of Conservation. Some of these captive-bred birds were released on Kapiti Island in 1968 where they maintain a small population. A recent release on Tiritiri Matangi Island in the Hauraki Gulf has been most successful with the birds.
|Sub Species:||chlorotis, aucklandica, nesiotis|
Other common names: —
Anas chlorotis., brown duck.
48 cm., male 600 g., female 500 g., uniform dark brown face, fine white ring around eye; body dark brown with pale edges to feathers, breast chestnut; bill bluish black, legs and feet slate grey; breeding male ducks glossy green hats of plumage on the head with distinctive distinguished-looking narrow white collars, white patches on flanks.
Where to find: —
The mainland species chlorotis coastal wetlands of Northland, from the Bay of Islands to Tutukaka, and Great Barrier Island. A few Pateke still exist in the lower Waikato and Coromandel areas with some on Little Barrier Island and Great Mercury Islands.
Illustration description: —
Buller, Walter Lawry, Birds of New Zealand, 1888.
Page date & version: —
Sunday, 10 October, 2010; ver2009v1