Topic: Australasian Bittern
Topic type:
The Australasian Bittern also known as Matuku Herepo has the 2008 National Threat Category of Nationally Endangered. It lives in wetlands and around the peat lakes of Te Arai.
Peter Langlands Photography
Australasian Bittern (Botaurus poiciloptilus)
A solitary bird that rests during the heat of the day and “at eventide startles the ear with its four loud booming notes, slowly repeated, and resembling the distant roar of an angry bull” (Buller, 1888). Aside from this roar, the bittern is extremely shy, the birds will often freeze upright to merge with the reedy background of its habitat. The binocular setting of the bittern’s eyes enables the bird to look down when holding their head high in this freeze position.
Range and Habitat
The bittern prefers densely vegetated swamp and wetlands. In New Zealand they are widely distributed in the North, South and Stewart Islands, but are mostly found in Northland, Waikato, Bay of Plenty, Manawatu, southern Wairarapa and on the West Coast. Resident on Great Barrier Island and possibly Mayor Islands.
Biology
Breeding from September through to January. Nests are flat platforms of raupo, sedges and rushes merely a few inches above the water. Hatches 3- 5 eggs per clutch with 6 days between laying. This meams the chicks are often of disproportionate size. Incubation is completed solely by the female and takes up to 25 days. Chicks fledge (can fly) after 7 weeks.
Threats
Habitat loss, predation.
Conservation
Protection and restoration of our wetlands are key for the survival of the bittern. Rebecca Stanley (2010) wrote of the importance of preserving Te Arai's wetlands: "There is a coastal wetland at the mouth of the Te Arai stream and several small wetlands in and around the edges of the property. New Zealand wetlands (generally) have declined significantly since European settlement, with only 9.4% of their original extent remaining (Ministry for the Environment & DOC 2007), and those that remain are under severe threat from human activities with most wetlands in lowland areas in private ownership. Freshwater wetlands have been seriously depleted in the Rodney District with only 3% of the wetlands formerly found in the district remaining (Lindsay et al. 2007).
Shona Myers(2010), ecologist formally of the ARC also commented on the importance of the Te Arai Lakes district for the Australasian Bittern:
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