The plight of a precious fish called Gollum has trumped plans to dam a Central Otago river.
A Government-appointed special tribunal has found that a water conservation order on the Nevis River should be amended to prevent damming because of the existence of a rare, indigenous fish.
Forest & Bird Otago-Southland field officer Sue Maturin called the decision "unbelievable".
"It's great news that the tribunal recognises the importance of a very special endemic fish. It also saves one of Central Otago's least-modified river valleys."
The Gollum galaxiid's official name is Galaxias gollumoides. The fish is ranked as "nationally vulnerable" by the Department of Conservation.
Ironically, Gollum's case was fought by a sports fishing body.
Fish & Game Otago chief executive Niall Watson said he was disappointed additional angling values sought for the order were not recognised. "But the river has extra recognition and is protected from hydro development," he said.
"The Nevis can start to be one of the jewels in the natural resource crown of Central Otago."
Freshwater ecologist Richard Allibone, who gave evidence for Fish & Game at the tribunal hearing, said the fish could only be found in the Nevis River – although there were related species in parts of Otago, Southland and Stewart Island.
"If you muck it up, that's it, it's gone."
The decision is thought to be the first time an indigenous fish has been identified as an "outstanding characteristic" of such an order.
Allibone said that opened the possibility that species under greater threat – such as the Canterbury mudfish and bignose galaxias, and upland and lowland galaxias in the Upper Waitaki – could be protected by conservation orders on smaller waterways.
Pioneer Generation, which has plans for a eight kilometre long lake and 45-megawatt power scheme on the river, is yet to decide whether to appeal.
Tribunal members Richard Fowler (chairman), Carolyn Burns and Rauru Kirikiri said the fish must be considered an outstanding characteristic of the river.
They said there was considerable doubt fish barriers above a reservoir would prevent long-term, unintended disastrous effects on the Gollum galaxiid species.
"Quite apart from the fact that the species is unique, there are some genetic and geological dimensions to that uniqueness that still are only partially understood."
Pioneer Generation owns the lease on Ben Nevis and Craigroy stations in the Nevis Valley, which are going through tenure review.
- The Press
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