Yesterday, Avifauna Bird Park in the Netherlands announced a North Island brown kiwi has hatched as part of a worldwide breeding programme on 18 September – a Netherlands’ first. Avifauna didn’t announce the new arrival until it had survived its first crucial weeks when a lot can go wrong, but the animal is in perfect health. ‘The birth of a kiwi chick is very special, especially since there are only 60 kiwis in zoos outside New Zealand,’ zoo keeper Dennis Appels told the press.
The Dutch Bird Park is one of 16 zoos in the world to contribute to a captive breeding programme of zoological institutions for the North Island brown kiwi outside New Zealand, the only country the kiwi can be found in the wild and which has its own captive management plan for this native flightless bird. Avifauna is the only zoo to have produced a kiwi chick this year. ‘The secret is a solicitous father and peace and quiet,’ Appels said, indicating that taking care of the brood is left to the male. It is not yet known what sex the chick is. This will be determined by a DNA test on the animal’s feathers in a few weeks’ time.
During a press moment, in the presence of New Zealand’s ambassador to the Netherlands Lyndal Walker, the kiwi’s name was announced – Tuatahi. In honour of New Zealand’s original inhabitants it is a Maori name, and it means the first, or the first one, reflecting its significance.
From Saturday 13 October the kiwi chick will be publicly weighed and measured for the rest of the month every day at 14:00 hrs, to allow the public to see the new arrival, for spotting a kiwi in their enclosure, Night Safari — the nocturnal house, is not easy.
Kiwi’s in captivity
The first recorded captive-held kiwi was in 1851, when female brown kiwi arrived at the Zoological Society of London. They lived for several years and produced eggs.
In 1912, a wild-caught brown kiwi first appeared on records at Wellington Zoo.
The first record of a brown kiwi chick hatching in captivity was in 1945, at the Hawke’s Bay Acclimatisation Society’s game farm, near Napier, New Zealand.
The first kiwi to be displayed in nocturnal houses were brown kiwi, displayed at Auckland Zoo and Otorohanga in 1972, while in 1975 the Smithsonian’s National Zoological Park was host to the first kiwi born outside New Zealand.
The first artificially incubated full-term brown kiwi egg hatched at Otorohanga, in 1977.
In the 1990s, Operation Nest Egg was first used to bring wild-laid eggs into captivity. The first release of sub-adult brown kiwi in the wild was achieved in 1995. A more complete history can be found in the Captive Management Plan for Kiwi.
The kiwi and its conservation status
Kiwi are flightless birds, having only vestigial wings and no external tail. Brown kiwi males average 2.2 kg in weight and females 2.8 kg, length is 45 – 55 cm. They are largely nocturnal and make loud, far-carrying repeated shrill (male) or guttural (female) calls, mainly in the 2 hours after dark and again before dawn. Daytime dens and nests are made in burrows, hollow logs or under dense vegetation. The kiwi egg is exceptionally large at about 15 – 20% of the female body weight. The incubation period for a kiwi egg is also long, around 80 days, with the incubation carried out by the male where it concerns the brown kiwi.
Unlike most birds kiwi have an exceptional sense of smell, with nostrils uniquely placed near the tip of their long (65−155 mm) bill. The bill is used for probing for food, not defence, and has specialized vibration/pressure-sensing nerve endings at its tip to detect prey movement. The birds are strong runners and are capable of swimming rivers. Kiwi have a lower body temperature than most birds (37 – 38˚C).
The population of North Island brown kiwi in the wild have decreased through a combination of habitat loss and predation by mammalian predators, especially dogs, ferrets and stoats, for which the flightless birds are an easy catch. The North Island brown kiwi (Apteryx mantelli) is classified as Vulnerable by the IUCN Red List of Threatened Species™. There are an estimated 68,000 of these birds left in the wild.
(Source: Avifauna Bird Park news release, 11.10.2018; DutchNews.nl news, 11.10.2018; Smithsonian National Zoological Park; Kiwis for kiwi, captive facilities; Zoo & Aquarium Association brown kiwi fact sheet)