Te Urewera Mainland Island (TUMI)

Te Urewera Mainland Island is located in the Waimana Valley at the northern part of Te Urewera National Park. The Bell Rd turnoff from State Highway 2 is one of the main access routes to this part of the park. The road travels about 30km up the valley to the Matahi Valley Rd end. Most of this road is unsealed but well maintained.

TUMI is one of 6 DOC mainland islands and with an operational area of 50,000 hectares is the largest restoration project of its type in NZ. TUMI is set in rugged hill country and contains every North Island native bird except for weka and has over 650 native plant species.

TUMI, judged one of Australasia's top 25 ecological restoration projects, was established in 1996. Initial work focused on Otamatuna region where a remnant population of North Island kokako (and other plants and animals) were being protected by controlling possums, rats & stoats. This region became known as a Core Area, distinguishing itself from surrounding areas (Background Areas) where only possum control was being done. Currently there are five Core Areas spread through the northern Te Urewera, resulting in pockets with low pest numbers, allowing native birds and plants to thrive and then spread from these sites.

Unlike many other similar projects in New Zealand which use toxins, within TUMI control of animal pests (including possums, rats, stoats, deer, feral cats & dogs & pigs) is mainly by trapping. On the ground work generally falls into two categories: pest control & monitoring. Several species are monitored as indicators as to how well pest control is proceeding. Included are 1) Kokako – whose eggs and chicks are often killed by rats and possums. 2) Kiwi and Whio whose young are vulnerable to stoat predation. 3) Native mistletoes which are a favourite food of possums. Also monitored are the number and diversity of forest birds, the condition of tawhero (kamahi) a forest canopy tree, the abundance of rat, possum and deer and the number of seedlings preferred by deer.

The most significant indication of success so far is the increase in number of kokako pairs in the Otamatuna Core Area. In 1993 it was as low as eight pairs, increasing steadily to 2006 there was an estimated 112 pair. Other successes include significant increase in numbers of whio, kereru, mistletoe, kiwi and an improved canopy.

Within TUMI a strong emphasis has been placed on the use of traps for control of possums, stoats and rats. Much has been learned about the effectiveness of various traps and trapping regimes and has been passed on to their conservation managers and findings absorbed into DOC practice methods. The work is ongoing and there are still lessons to learn, the use of traps is a major point of difference with other projects, but recovery of vulnerable species in this rugged environment is possible. The Core Area/Background Area model is feasible for ecosystem restoration, however much is yet to be refined and this is where work in the coming years will be largely focused.

Written by Wendy Martin