Dannevirke: Rare fish find in farm gorge

Jack Waller and his mother Sarah-Jane Third with the giant kokopu. This species are primarily coastal and do not usually penetrate inland very far, however, this specimen was found in a stream on Brian Hales' Wimbledon farm.

Eleven years after Weber schoolboy Khan Coleman made a discovery on Brian Hales' Wimbledon farm which had the scientific and conservation world buzzing, there's been another significant find on the property.

Khan and Mr Hales discovered the peripatus in 2005, more than 40 years since it had been seen in the area. Known as the missing link between segmented worms and insects, even David Attenborough had been to New Zealand searching in vain for the peripatus.

The giant kokopu found at Wimbledon.

Now, in a small stream on the Wimbledon farm, Sarah-Jane Third and her children Jack and Hazel-Jane Waller have made another important ecological discovery.

"They have found a giant kokopu which were once common in the area and around New Zealand," Mr Hales said.

"But, like all migratory fish they have been struggling to survive with the impact of culverts creating waterfalls, preventing their return upstream migration.

"I remember them as a child and we called them native trout. I have searched for the last 40 years and have not been able to find any. People may have seen these years ago, but they are now very rare."

Mr Hales said the giant kokopu's habitat on his farm is a very small stream, coming out of an inaccessible gorge. It is enclosed with bush including southern rata as a canopy.

"The stream is also the home of the remaining freshwater crayfish in the area," he said.

Senior Weber School teacher Sarah-Jane Third and her family were thrilled to have found the elusive giant kokopu.

"While camping at Brian Hales' farm last week with my family we went exploring the creeks to see what we could find," Sarah-Jane told the Dannevirke News. "Turning rocks for koura we found a very well hidden fish, unsure what it was we took some photos and took them to Brian. We searched books and finally identified it as a giant kokopu. We were lucky enough to find two while we were there and have since found out they are threatened."

Mr Hales contacted Mike Winterbourn of the University of Canterbury regarding the discovery.

"He remembers our conversations about the peripatus and is pleased I've been able to set up protection for them," he said.

Although Mr Winterbourn said he didn't know a lot about giant kokopu, he confirmed their numbers were declining.

What are giant kokopu?

* The giant kokopu is the largest member of the Galaxiidae family. Specimens of more than 450mm in length have been reported, although fish in the 200-300mm range are far more common. The profusion of golden spots and other shapes on the bodies of larger fish are very distinctive.

* The giant kokopu was the first Galaxiidae to be discovered and it was its colour pattern which led to the generic name Galaxias, referring to the profusion of stars in the galaxy.

* Giant kokopu are one of the whitebait species and are primarily a coastal species, not usually penetrating inland very far.

* Once they were quite common, being regularly encountered and used as a food source by early settlers and Maori.

* Today they are less common and are currently classed as a Category B (second priority) threatened species.

* Although uncommon, the species is widely distributed throughout New Zealand due to its diadromous (fish that migrate between the sea and fresh water) life history.

* Most of the records for giant kokopu (87 per cent) originate from Westland, Southland Wellington, and Waikato.

* Few giant kokopu have been recorded in the east coast of New Zealand.