Nature and conservation

The Ruahine Ranges form part of the North Island main dividing range, dropping in altitude as they progress south. The range is geologically young (1-2 million years), with a high level of erosion from its many fault lines, a poor soil structure and harsh climate.

A unique characteristic of the range is that it rises abruptly while being relatively narrow. This significantly impacts on the ranges’ weather, providing very high rainfall events (one trig station in the middle of the range records an annual rainfall of 5 m). Rivers and streams deeply dissect the area, forming a network of significant rivers.

There are few foothills in the park, with the ranges rising steeply from 500 m to 1686 m. While the southern third of the park is only 8 km wide, the deep valleys and broad rolling tops of the northern range span up to 24 km. The park is approximately 100 km in length.

The copper deposits in the upper Coppermine Creek to the south are another special feature of the park.

Vegetation

Vegetation in the park varies as the altitude changes. The forests in the north are generally a mix of podocarps, including red beech, rimu, miro, matai and mountain beech, with kahikatea dominating swampy areas. On the wide open tops the forests give way to sub-alpine shrubland, tussock grasslands and summer flowering herbfields.

Further south wet and cloudy conditions favour the dense growth of leatherwood (tupare), forming the largest unbroken expanse in the country. Throughout the park the understory is rich in ferns and small trees and shrubs like horopito, rangiora and mahoe.

Lake Colenso

Lake Colenso, and its surrounding basin, is a unique scenic, ecological and historic feature of Ruahine Forest Park. Its Māori name, Kokopunui, refers to the presence of native fish, and eels, in the lake and thus its significance as a source of food.

From an ecological point of view this remote lake has significant value. There are no introduced weeds or fish in the lake and the surrounding swampy basin is the only area of lowland podocarp forest found in the Ruahine Range. This podocarp forest and the surrounding red beech forest provide a habitat for more than twenty species of native birds including whio and kaka.

The lake is surrounded by 150 m high limestone escarpments which are an impressive sight and an effective barrier guarding the special features of this isolated mountain lake.

Native animals

Visitors may be treated to the sights and sounds of numerous native birds including the tui, kereru (wood pigeon), tom-tit (miromiro), fantail (piwakawaka), grey warbler (riroriro), bellbird (korimako), and kakariki (parakeet). The rare blue duck (whio) lives in mountain streams and the New Zealand falcon (karearea) and North Island kaka exist at higher altitudes. Native animals in the park include skinks and geckos (moko), bats (pekapeka) and large land snails.

Introduced animals

Introduced animals include red deer, pigs, goats, possums, mustelids, and other animals that damage native plants and animals. Recreational hunters contribute to pest control measures by targeting deer and pigs. Trout can also be found in some rivers.

Ruahine Deer Working Group

A working group has been established to provide a forum for hunters (both recreational and commercial) and DOC to discuss issues relating to hunting and inform decisions for management of deer in the Ruahine Forest Park.

The group is working towards a common goal of a sustainable hunting resource/game animal population existing in harmony with a resilient ecosystem in the Ruahine Forest Park. If you would like to find out more about the group, email manawatu@doc.govt.nz.