The Ōkārito Kiwi Sanctuary protects rowi.
The Sanctuary covers 11,000 hectares of lowland forest near Ōkārito, on the West Coast of the South Island, near Franz Josef/Waiau township.
Rowi were identified as a separate species from brown kiwi in 2003. With a population of only about 375 mature birds, rowi are one of New Zealand’s most threatened native species and ranked as ‘threatened: nationally critical’.
The Department of Conservation (DOC) is looking for the most effective combination of management options to protect rowi in a sustainable and non-invasive way.
At present, Ōkārito Kiwi Sanctuary largely uses Operation Nest Egg to boost its slow-growing rowi population and, while highly successful, the technique is both labour-intensive and invasive for the birds. DOC is investigating combining Operation Nest Egg with pulses of stoat control to see which combination best protects birds in the wild.
As part of Operation Nest Egg, eggs and wild-born chicks are taken to the West Coast Wildlife Centre in Franz Josef/Waiau. Newly hatched chicks are kept in an enclosure to develop their nocturnal instincts, and are then released onto predator-free islands until big enough to defend themselves against stoats. Rowi chicks don’t put on weight as quickly as other kiwi species, taking more than 12 months to reach a stoat-proof weight. When juveniles are released back into Ōkārito Kiwi Sanctuary, care is taken to avoid territory already occupied by adult pairs, as rowi are fiercely territorial.
Using Operation Nest Egg means more than 90% of fertile eggs hatch successfully—without it, as few as 5% would survive.
An example of progress
Following the 2006/07 and 2007/08 breeding seasons, 25 juvenile rowi were released back into Ōkārito Kiwi Sanctuary. In 2010, 36 young birds were brought home, and 20 of these were released into North Ōkārito Forest. This area was once part of the rowi’s natural range, but no birds have lived there for many years. In 2015 the largest release of rowi back to Ōkārito with 50 young birds being released back to the forest. The target is a total population of 600 rowi by 2018.