This year has already been the most successful breeding season to date for endangered North Island brown kiwis (Apteryx mantelli) at New Zealand's Pukaha Mount Bruce national wildlife center, and now the rangers who manage the program have an extra reason to celebrate: the May 1 birth of an extremely rare all-white kiwi.
The bird, named Manukura by elders from the local Maori tribe, is not an albino. It just has white feathers.
"As far as we know, this is the first all-white chick to be hatched in captivity," Pukaha Mount Bruce chairman Bob Francis said in a prepared statement. The kiwi population on Little Barrier Island, where the chick's parents came from earlier this year, "has birds with white markings and some white kiwi, but this was still a big surprise." No white kiwis were brought to Pukaha, but the parents may have carried the genes for white feathers.
Populations of all five kiwi species, all of which are endemic to New Zealand and either endangered or critically endangered, were shrinking by at least 6 percent a year, according to a 2009 survey, mainly due to predation by European stoats (Mustela erminea). The North Island brown kiwi is actually the healthiest kiwi species, numbering around 35,000 birds. Other species, such as the rowi (formerly Okarito brown) kiwi (Apteryx rowi), are down to just a few hundred individuals.
Manukura's birth has been hailed as a tohu, or sign of new beginnings, by Maori tribal elders. The chick's name roughly translates to "chiefly status".
Like all of the chicks born at in the breeding program, Manukura will be hand-reared for the first month or two, and then kept in captivity for another four to six months. When the chicks are old enough to fend for themselves, they will be released into the 940-hectare sanctuary, although Manukura may or may not be among them. "A white kiwi might really stand out, making it more vulnerable," said area manager Chris Lester of the New Zealand Department of Conservation. "We want to ensure that as many people as possible get a chance to see it, and that we keep it as safe as possible."
All told, 14 kiwis have been born at the sanctuary this season, the highest number since the breeding program began in 2003. That's a significant rise in births compared with the last few years: only 10 chicks were hatched between 2005 and 2010. Fertile eggs are collected from the forest in the sanctuary and hatched in the kiwi nursery.
Photo courtesy of New Zealand Department of Conservation