The Rimutaka Forest Park Kiwi Project is now in its 8th year with a trapping and tracking volunteer base of over 70. The initial goal was to move a group (about 10 birds initially, in pairs) of North Island Brown kiwi from captivity in other locations nationwide to a 1000 hectare, predator-controlled site in the Park to establish a viable, self-sustaining Kiwi population.
Following our successful adult kiwi translocation from Little Barrier Island in April 2008, when 20 additional Brown Kiwi were added to our growing population, the number of adult and juvenile kiwi roaming the Turere and Whakanui Valleys has now reached about 100, with at least 5 chicks hatched recently in the Park itself and a few chicks hatched from eggs laid by our kiwi from earlier releases at Pukaha Mt Bruce. These birds will eventually be returned to the Park.
Now more than half the birds in the Rimutaka Forest Park have been born and raised in the Park!
Two of the older birds from the original release (Koniwi and Milo) subsequently died of natural causes, but many new chicks have been successfully hatched from eggs laid and incubated by four of our founding population of kiwi pairs and several other of the translocated Little Barrier Island pairs.
At least four birds, Fern, Billy, Otautahi and Waikiwianui, were savaged and killed by dogs.
Despite the losses to dogs, the Turere release area has proved to be an excellent foraging and breeding habitat for kiwi survival!
The initial (stoat trapped) Turere catchment release area was over 1000 ha in size, the minimum considered necessary for a self-sustaining population of brown kiwi.
Additional trap lines have since been extended into large areas of native bush bordering the original release area, providing plenty of space for the inevitable dispersal of our birds as the population increases. The trapped areas now extend over 3000 hectares.
The humane Doc 200 and 250 kill traps are checked fortnightly in the summer and monthly in the winter. Peak season for stoat population is Jan/Feb when the kits are leaving the nest and dispersing.
While fully grown brown kiwi (birds over 1200 grams) are capable of defending themselves against attack by stoats, their eggs and young chicks are vulnerable.
A robust predator control regime that includes the boundary buffer and internal stoat trapping programme, along with continued monitoring of the brown kiwi population, will minimise the threat to young kiwi.
Because there is a problem with rabbits and hares in the Catchpool Valley and Orongorongo Valley, we have a grave fear that eventually we will be visited by ferrets - which are much larger and even deadlier to adult kiwi and chicks than stoats, so we have recently deployed some larger (DoC 250) ferret traps as well.
Emu egg (left) seen alongside a Kiwi egg. An interesting comparison, considering the relative size of the fully-grown birds! Photo credit: Susan Ellis