Before humans arrived, much of the region was forested, with some tussock grass in the lowlands and also in valleys amid forests. Snow tussock predominated above the treeline.
Human impact on the plains
Polynesians who arrived around 1250–1300 CE burnt extensive areas of vegetation. As a result, much forest and woodland was replaced by red tussock and scrub. Harakeke (flax) sprang up in the wetter peat swamp and bog lands.
Some large stands of bush remained, particularly in wetter western areas and along the coast: mostly mataī and rimu in the lowlands, and three varieties of beech in the uplands and mountains. Kānuka, mānuka, bracken and fern grew in forest clearings and margins.
From the 1850s onwards, European settlers cleared the forests and tussock, often by burning, and then planted introduced grasses for grazing animals.
Fiordland has the greatest extent of unmodified vegetation in Southland. The forests are mostly silver and mountain beech, with podocarps such as rimu, miro and Hall’s tōtara at lower levels. But the rich understorey of plants has been damaged by introduced game species such as red deer, tahr and chamois, and by possums.
A drastic reduction in red deer numbers from the late 1960s has allowed many native plants, particularly alpine species, to become re-established.
Fiordland remains a treasure chest of rare and endemic plants – including several species of snow grass, herbs, tree daisies, speargrasses and buttercups.
Only in Fiordland
Around 10% of Fiordland’s 3,000 insect species are endemic to the region. Many are big – giant weevils, wētā, snails, wasps, slugs, and the country’s largest caddis. Other oddities include egg-laying worms, a chafer beetle, the short-horned grasshopper, alpine cicadas, 11 species of stonefly or stoners (aquatic insects), and 100 species of brightly coloured alpine moth.
The flightless moa, now extinct, was once a ‘one-stop shop’ for Māori, who killed the huge birds for food and to make clothing.
Ground birds such as kiwi and weka freely roamed the forest lowlands before the bush and trees were burned and cleared, and stoats, weasels, cats, rats and possums arrived.
Fiordland was the last natural refuge for the flightless takahē. In 1948, Invercargill doctor Geoffrey Orbell rediscovered the bird in the Murchison Mountains, after it was believed to have been extinct for 50 years. In the 2010s around 300 takahē survived – 170 of them in the Murchison Mountains.
There may also be some kākāpō (rare endangered parrots) in the wild in Fiordland, but this is uncertain – the major kākāpō population is now on Whenua Hou/Codfish Island, off the west coast of Stewart Island.
An area around Lake Hauroko is the only South Island habitat of the endangered brown teal.
Torment in paradise
In summer the sandfly, which inflicts intensely itchy bites, is the bane of unprepared tourists visiting beautiful Fiordland. In 1773, the British explorer James Cook described the sandfly as ‘that most mischievous animal’. 1
Southland rivers were home to eels, bullies and four galaxiid species (two kinds of kōkopu, īnanga and kōaro). The juveniles of these galaxiids are usually known as whitebait. Eels, lamprey and torrentfish spawn and breed in Fiordland rivers.
Brown trout were first liberated in Southland waters in the 1870s, and rainbow trout in the early 1900s. Atlantic salmon are found in the Waiau river system, including lakes Te Anau and Manapōuri.
Pods of bottlenose dolphins are found around the Southland coast. Some swim up the tidal stretch of the Hollyford River to Lake McKerrow, possibly in pursuit of trout. A close-knit group of about 70 bottlenoses live in Doubtful Sound, moving out to sea when the inner fiord is covered in ice.
A 300- or 400-strong pod of Hector’s dolphins, the world’s rarest and smallest, and the only dolphin endemic to New Zealand, is semi-resident in Te Waewae Bay.
Southern right, humpback and sperm whales are occasionally seen in Foveaux Strait and off the Fiordland coast, migrating to or from Antarctica.