On 27th January, a group of 30 people involved in the project, gathered at Puketukutuku to complete the fence appropriately with karakia and celebration, following years of planning and months of hard work. Workers from the Lake Waikaremoana Hapu Restoration Trust assisted by local volunteers worked on the fence over recent months to produce a structure described by Dr McLennan as a “beautifully constructed symbol of commitment to kiwi.”

“It’s not just a fence, it’s a work of art,” Dr McLennan said.

Like human teenagers, young kiwi like to get out and see the world before they settle down to the serious business of producing chicks. Kiwi “teenagers” can travel many kilometres before they finally settle in their own territory. Sadly, once they are outside an area where predator control takes place, the chances of any chicks they produce surviving to adulthood are slim. By keeping the “teenagers” in the protected area of Puketukutuku, it is expected that they will settle and produce chicks to boost the kiwi numbers on the peninsula as quickly as possible. When numbers have reached the capacity of the peninsula to support the birds, the fence will be removed. The increase in bird numbers on Puketukutuku will provide a sound population base for the survival of kiwi in the Waikaremoana catchment.

Intensive predator control has been undertaken on the 750 hectare Puketukutuku Peninsula since 1995 as part of a project started in 1993 by Dr McLennan, a scientist with Landcare Research Manaaki Whenua. Having gained the support of the hapu and the Department of Conservation (DOC), Dr McLennan obtained funding to study the reasons that kiwi numbers are declining in mainland forests. With a focus on birds in the Waikaremoana catchment, the study investigated the role of predators, particularly stoats in reducing kiwi populations. The large-scale field experiment proved that kiwi survival increased following intensive predator control.

“Predator control on Puketukutuku has been incredibly successful from a national perspective. It has been attempted elsewhere not always successfully, but Puketuktuku is a wonderful exception, partly due to geography and partly because the programme is incredibly well run,” Dr McLennan said.

Continual monitoring and refinement of the trapping regime on Puketukutuku led to additional trap lines being established in 2001, resulting in excellent stoat control and a rise in the rate of kiwi chick survival on the peninsula. Concurrent monitoring of sites with no predator control indicated that the number of chicks that survived to adulthood was extremely low. Dr McLennan’s work proved that intensive predator control is essential to the survival of kiwi on the mainland.

In years when stoat numbers have been particularly high, even intensive trapping has not been enough to prevent the loss of kiwi chicks. In these years, chicks from Puketukutuku have been moved to Westshore Wildlife Reserve in Hawke’s Bay to be raised in captivity until they are large enough to be no longer vulnerable to predation and can be returned to the Waikaremoana forest. In 2001-2002 DOC and local hapu members built a 1.5 hectare stoat-proof enclosure on private Maori land on Puketukutuku to provide extra protection for chicks in years when predator number are high.

Having established that stoats are a major cause of kiwi population decline, but that a combination of intensive pest control, and, when necessary, extra protection of chicks can reverse that decline, the focus of research changed in 1999 to the dispersal of juvenile kiwi. Between 1993 and 2002, the population of adult kiwi on the peninsula increased from about 24 to about 50. The increase would have been greater if all the young produced on the peninsula stayed there. But at least half of the young birds left Puketukutuku to establish territories elsewhere. It is estimated that the carrying capacity for kiwi on the peninsula is about 150 to 200 adults. In order to maximize the conservation returns on expenditure, it was decided to build the kiwi population on Puketukutuku as quickly as possible by preventing the dispersal of young birds.

“Effective management has to be conducted on a scale appropriate to kiwi innate biology. Puketukutuku is too small a scale. Computer modeling has shown that the correct scale would be ten to eleven thousand hectares but the level of pest control required would be expensive. The simplest way to reach the scale was to build a fence to prevent young kiwi from leaking out. The fence will be temporary. Once carrying capacity has been reached, it will be taken down and may be used elsewhere in the catchment, perhaps on Whareama Peninsula,” Dr McLennan said.

The project has received widespread support from a variety of sources including, Landcare Research Manaaki Whenua who were involved until 2002, Bank of New Zealand Kiwi Recovery Trust which supports the work of the Lake Waikaremoana Hapu Restoration Trust, Lotteries Commission Environment and Heritage funding and members of the public who have made private donations. DOC biodiversity work in the area is supported by Genesis Energy and Gallaghers worked with the hapu to supply the solar panel electric fence unit.

A key figure in the project was hapu Field Manager, Robert Waiwai, who basically led the charge with the building of the fence. On the celebration day, DOC Area Manager, Glenn Mitchell dedicated the fence to Robert in recognition of the huge personal effort he made towards the project. The fence took 54 twelve-hour days to construct with work undertaken while hapu members continued to maintain the intensive trapping regime both on the peninsula and in a 750 hectare buffer zone, as well as monitoring and other tasks.

Since 1995, Conservation Corps members and a variety of volunteers have contributed to the hard slog of setting and checking traps. DOC staff have provided continuity over the years working on tasks such as obtaining approval to undertake various aspects of the project in a national park, trapping, monitoring and analysing information to improve techniques and management. Dr McLennan paid tribute to Glenn Mitchell and his team for their work over the years and said that department support has been fantastic.

Lisa Waiwai of the Lake Waikaremoana Hapu Restoration Trust said that the fence is the first of its kind and hapu members are proud to be part of a new concept.

“We are happy to be part of anything to help the kiwi. From a Maori perspective, we consider kiwi to be part of our whanau,” Mrs Waiwai said.

DOC Biodiversity Programme Manager, Dave King said that visitors to the area should be aware that the fence is electrified and anyone touching it would receive a shock.

“There are warning signs on the fence and notices explaining why it is there. Part of it is quite close to the Waikaremoana Great Walk. Boaties should also be aware that the end of the fence extends a short way into the lake,” Mr King said.

“Puketukutuku is now an island as far as kiwi are concerned and we know they will survive in the long term. People with a range of skills all contributing at various levels have brought us to this stage. They say it takes a village to raise a child. This project shows it takes a village to restore a kiwi population,” Dr McLennan said.

DOC kiwi information:
Paul Jansen, Phone: (04) 471 3236 or 025 410 026

DOC media liaison:
Jill Hudson, Phone: (06) 869 0468

Lake Waikaremoana Hapu Restoration Trust:
Lisa Waiwai, Phone: (06) 837 3700

Bank of New Zealand Kiwi Recovery Trust:
Kieron Goodwin, Phone: (09) 375 1084 or 029 478 4610