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Kawau Island Fauna Kiwi – North Island Brown Islands such as Kawau play an important role in the protection of this endangered species as predator control and habitat are more easily managed within an island setting. The Department of Conservation conduct surveys on Kawau as part of the national kiwi recovery programme, Ideal habitat sites are identified and examined for signs of kiwi presence – probe holes where they have been feeding, signs of foot prints, burrows and faeces. On a series of consecutive nights male and female calls are recorded and plotted, together with habitat characteristics and weather conditions. Kiwi tend to live in pairs, forming monogamous couples generally for life. Some bonds have been known to last 30 years. They are extremely territorial birds that protect their patch (which can be as much as 30 hectares) by calling and chasing intruders. Young kiwi leave the nest at just three weeks old, weighing only 200 grams. Small and slow they are easy prey and very few survive to 12 months when they reach the critical size that enables them to stand up to most predators. Kiwis prefer areas of undisturbed native bush with permanent ground water – areas with plenty of earthworms, weta nymphs, spiders, fallen fruit and seeds, lavae of beetles and cicadas. It is the only known bird to have nostrils at the end of its bill enabling it to sniff out food a bill-length below the earth surface. Threat to kiwi There are three main threats to the Kawau Kiwi population: • Predation • Competition • Habitat loss Predation is direct and immediate and can dramatically reduce the size of the population in a short space of time. Cats and dogs brought to Kawau by visitors, along with resident rats and possums, can kill the birds or steal their eggs. The flightless kiwi has no defence against these animals. No animals may be brought into the Department of Conservation Reserves for this reason. Private land owners are asked to ensure that domestic animals are confined to their property and are prevented from roaming. The kiwi on Kawau also compete for habitat with possum and wallaby. The wallaby eat the native bush seedlings preventing forest regeneration whilst possums damage the more mature trees. The future of Kiwi on Kawau Kiwi surveys show that the kiwi population here is not large and therefore vulnerable to disturbances in the environment. It is evident that the survival of the species is dependent on the control of predators and competitors. Responsible restraint of dogs and cats by owners and effective management of wallaby and possum populations are essential to prevent the extinction of kiwi on Kawau Island. Wallaby Sir George Grey introduced five species of wallaby to Kawau Island between 1860 and 1870. Four species are still found on the island today. Dama or Tammar Wallaby Macropus eugenii The most numerous species present on Kawau. It is small, about 50cm when full grown, with a short rat-like tail. It is silver grey in colour with reddish shadings on the shoulder. Parma or White-throated Wallaby Macropus parma The parma is a small brown wallaby approximately the same size as the dama. It has a long dark tail with a cream or white coloured tip. Its chin and throat are also whitish in colour. The parma was thought to be extinct in its native Australia by 1932. After its rediscovery on Kawau in 1965 many of the species have since been returned to Australia. Wallabia bicolor – Swamp Wallaby Brush tailed rock wallaby Petrogale pencillata This 55-60cm high wallaby is the most brightly coloured of those on Kawau. It has a coppery brown body with a dark bushy tail and dark markings on the face. It is very agile and can jump as high as four metres onto sloping trees. It is found in low numbers in grassy clearings above the cliffs. Swamp Wallaby Wallabia bicolour This large wallaby is sometimes referred to as the “wallaroo”. I grows to a metre in height and is a rich dark brown with a tapering dark tail. It is found over most of the island, although not abundantly, and lives in damp or scrubby areas. North Island Weka In 1982 there were estimated to have been more than 88,000 North Island weka in the Gisborne and East Cape area. However, between 1982 and 1986 most of the birds died during a long drought. Other declines followed cyclone Bola in 1988 and the release, or escape, of ferrets from a failed farming venture. The North Island weka is now critically endangered and numbers less that 7% of the number of North island brown kiwi. Between 75%and 84% of the remaining weka are on Kawau Island, which equates to between 3,000 and 4,200 birds - depending on climactic conditions. Since 1991 the weka around Mansion House have been monitored to determine nesting habitat, the numbers of chicks raised, the life span and interaction with other weka and species. The outcome of the study will determine when weka can be taken from Kawau Island to establish other populations in safe places. Weka are found all over Kawau, feeding on insects, fruit, and worms. They will also feed from rock pools and beaches. The weka around Mansion House enjoy the tit-bits provided by visitors and have been known to take chicks of other bird species as food. The weka can begin having chicks from as young as nine months. They usually breed only once a year between August and December and most pairs have two chicks. There are approximate equal numbers of male and female weka raised and most remain near where they were raised. Many chicks need to be raised each year to maintain the population as the mortality rate is high. The maximum time a weka can live is eleven years but most die in their first two and a half years. The high turn over rate is in part due to weka not finding enough water and food when the leaf litter and upper soil dries. Wallaby browsing on Kawau has resulted in the restriction of vegetation on most of the island to kanuka and this tree does not produce a deep moisture holding leaf. It is very likely that weka will be taken from Kawau Island for mainland liberations in 2003. They will be mixed with North Island weka from other populations to maintain the gene pool. Dr Tony Beauchamp DOC Northland 1999. Gallirallus australis greyi. North Island Weka Kawau Birdlife Common Name Blackbird Chaffinch Cuckoo Shining Dotterel, NZ Duck, grey Duck, mallard Duck, shelduck (Paradise) Fantail Gannet, Australian godwit Goldfinch Gull, black backed Gull, black billed Gull, red billed Hawk, harrier Heron, blue reef Heron, white faced Kaka Kakariki Kingfisher, NZ Kiwi, brown Kookaburra Magpie, Australian Morepork Myna Owl Oystercatche, variable Parakeet Peacock Penguin, little blue Petrel, grey faced Petrel, white headed Pigeon, NZ Pipit Pukeko Rosella, eastern Shag, black Shag, little Shag, little black Shag, spotted Shearwater, flesh footed Shearwater, fluttering Silvereye Sparrow, hedge Sparrow, house Stilt, pied Swallow, welcome Tern, Caspian Tern, white fronted Thrust, song Tui Warbler, grey Weka, North Island Latin Name Tardus merula merula Fringilla coelebs gengleri Chrysococcyx lucidus lucidus Charadrius obscurus Anas superciliosa superciliosa Anas platyrhynchos platyrhynchos Tardorna variegate Rhipidura fuliginosa Sula bassana serrator Carduelis carduelis brittanica Larus dominicanus Larus bulleri Larus novaehollandiae scopulinus Circus approximans Egretta sacra sacra Ardea novaehollandiae novauhollandiae Nestor meridionalis Cyanoramphus auriceps Halcyon sancta vagans Apteryx australis mantelli Dacelo novaguineae Gymnorhina tibicen Ninox novaeseelandiae novaeseelandiae Acridotheres tristis Athene noctua Haemotopus unicolor Cyranoramphus species Pavocristatus Eudyptula minor Pterodroma macioptera gouldi Pterodroma lessonii Hemiphaga novaseelandiae Anthus novaseelandiae Porphyrio porphyrio melanotus Platycercus eximus Phalacrocorax carbo Phalacrocorax melanoleucos Phalacrocorax sulcirostris Stictocarbo punctatus Puffinus carneipes Puffinus gavial Zosteroops lateralis lateralis Prunella modularis occidentalis Passer domesticus domesticus Himantopus leucocephalus Hirundo tahitica neoxena Hydroprogne caspia Sterna striata Turdus philomelos clarkei Prosthemadera novauseelandiae Gerygoneigata Gallirallus australisgreyi