$300,000 Worst Fish Machines Idle Under Waikato Regional Council Watch

The gear was part of Waikato Regional Council's plans to help eradicate koi carp, but has not been used since 2017-18 and has fallen into disrepair (file photo)

Mark Taylor / Stuff

The gear was part of Waikato Regional Council’s plans to help eradicate koi carp, but has not been used since 2017-18 and has fallen into disrepair (file photo)

Part of a $300,000+ koi trap and digester operation, currently inactive at Lake Waikare, may finally be revived thanks to the marae’s efforts to trap and treat nuisance fish.

The CarpN Neutral Project at Lake Waikare was launched to much fanfare by the Waikato Regional Council in 2012, as a way to help remove nuisance koi carp from the lake and use them for environmentally beneficial products.

But Waikato Regional Council Integrated Watershed Management Chairman Stu Husband said this month that the project had recently “lost its legs”.

Requests by Thing show that the trap and digester have been mostly inactive at Lake Waikare since 2017-2018, with the trap in “poor condition” and the digester, now sitting in a shipping container, having reached the “end of its life” .

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The council said the project cost about $300,000 to set up, which involved funding from the Waikato River Authority (WRA), the council and Genesis Energy. Operating costs were approximately $50,000 per year.

In a statement, the council’s director of integrated watershed management Greg Ryan said the digester, which costs around $120,000, was taken out of service after it failed in 2017-18 because it was too expensive to to fix.

He said it felt at the time that the proof of concept – turning koi into products that helped the environment – ​​had been proven.

The trap, which a spokeswoman confirmed cost $228,000, sat “out of the water,” Ryan said.

When asked why the equipment had not been actively used in recent years, Ryan said: “This project has been an opportunity to test the viability of commercializing the capture and processing of nuisance fish, and this information has been shared with interested parties. »

However, he confirmed that the council was happy that a Tainui marae collective, Te Riu o Waikato, was using the trap for its koi management initiatives “although it is in poor condition and would need to be checked for its integrity”.

Tawera Nikau of Te Riu o Waikato says they are looking to use the idle koi trap to tackle Lake Waikare carp:

Kelly Hodel / Stuff

Tawera Nikau of Te Riu o Waikato says they are looking to use the idle koi trap to tackle Lake Waikare carp: “Anything we can use to extract koi from our waterways, we will be looking at the use.”

Te Riu o Waikato President Tawera Nikau confirmed that his group plans to use the trap to remove as many koi as possible from the lake and offset the expense by using them for pet food, burley and the fertilizer.

“Our main problem is getting them out of the lake,” he said.

“Anything we can use to extract koi from our streams, we will seek to use.”

Some biomass studies were currently underway with the equipment, Nikau said. But the organization wants to make sure the trap is safe before they start using it on any scale. She asked the Ministry of the Environment for funding for its upgrade.

Ryan, meanwhile, said $250,000 he set aside in 2021-22 for a joint koi management project is being used, in part, for koi biomass trials with Te Riu o Waikato and the Department of Conservation.

Other uses of the silver are identifying sites for nuisance fish barriers, increased monitoring and supporting community koi eradication initiatives.

Ryan said DoC and Te Riu o Waikato also won nearly $490,000 in koi-related funding from the WRA.

Elna M. Lemons