30 Dec 2025

Te Arawa Lakes Trust battles invasive gold clams

8:38 pm on 30 December 2025
The spectre of freshwater gold clams looms over Northland's Lake Taharoa as the busy summer tourist season looms. The clams are New Zealand's first invasive freshwater pest shellfish.

The invasive gold clams. Photo: Supplied / MPI

Te Arawa Lakes Trust and local councils are banding together in the battle against invasive gold clams.

The trust is worried about the lakes in its area and the boaties coming to use them.

A hui at Lake Ōkāreka has resolved to stand up volunteers at boat ramps at several lakes to guide and greet visitors and help make sure boaties are playing their part.

The volunteers will not, the trust says, be restricting access.

"We're not saying saying to anybody, look, you can't come onto the lakes," Te Arawa Lakes Trust chairperson said.

He said volunteers would help ask if boats were clean and if they had been on the Waikato River.

That's where there is now a large stretch of the clams, after they were first found in May 2023 at Lake Karāpiro.

They have since been found elsewhere - in November at Lake Rotomanu in New Plymouth, which was then drained.

The find prompted a warning for boaties on the Whanganui River.

Adam Hartland has written for The Conversation about why the clams pose such a danger.

It's all hugely concerning for Te Arawa Lakes Trust which oversees 14 lakes in the Rotorua area.

"Given the significant number of boats that come into our area we have decided to be proactive to prevent any carriage of this invasive species into our lakes, because the impact is quite significant," Haumaha said.

Lake Ōkāreka, where the hui was held, has a number of boats taking to it for wakeboarding, water-skiing and other recreation activities, he said.

The meeting was between the Trust, Bay of Plenty Regional Council, Rotorua Lakes Council with government minister Todd McClay also in attendance.

The councils will be pitching in, Haumaha said.

"So we decided that, you know, this is about a community action... this is about the future of our lakes and protection of our waterways."

On the lake having to be drained in New Plymouth, "God forbid we ever have to do that here in Rotorua," he said.

Volunteers will be put at boat ramps to tell people of the importance of checking their boats and cleaning and drying them before coming onto the water.

Boaties will also be asked if they have been on Waikato River.

"We're not saying to anybody, look you can't come onto the lakes," he said.

Haumaha said the area's lakes were pristine and needed to be safeguarded for future generations.

He also urged arriving boaties to be kind to volunteers.

"People have just come out of the woodwork ready to step up, to make sure that they can stand alongside everyone for the protection of our lakes over the Summer period."

A roster will be drawn up for volunteers.

He said 11 lakes that are used by boaties have been identified, with about 29 boat ramps.

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