Te Arawa Lakes Trust is joining forces with local councils to mount a community-led defence against the spread of invasive gold clams into the Rotorua lakes district.
The trust, which oversees 14 lakes in the Rotorua area, has moved to act following the discovery of gold clams in the Waikato River, where the species was first detected at Lake Karāpiro in May 2023. The clams have since spread along a large stretch of the river, and further finds have raised concern across the country. In November, gold clams were discovered at Lake Rotomanu in New Plymouth, a find serious enough to prompt the draining of that lake and a warning for boaties using the Whanganui River. Adam Hartland has written about the threat the clams pose to freshwater ecosystems for The Conversation.
For Te Arawa Lakes Trust, the prospect of a similar infestation reaching Rotorua is deeply concerning. "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," said Haumaha.
A hui held at Lake Ōkāreka brought together the Trust, Bay of Plenty Regional Council, Rotorua Lakes Council, and government minister Todd McClay to work out a coordinated response. The outcome was a commitment to station volunteers at boat ramps across 11 lakes used by boaties, which between them have around 29 ramps. Lake Ōkāreka itself draws visitors for wakeboarding, water-skiing, and other recreational activities on the water.
The volunteers will meet and greet people arriving at ramps, check whether boats have been cleaned and dried, and ask whether boaties have recently been on the Waikato River. Haumaha was clear that the initiative is about guidance, not restriction. "We're not saying to anybody, look, you can't come onto the lakes," he said.
Both councils will contribute to the effort alongside the volunteer workforce. "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," Haumaha said.
The possibility of having to drain a Rotorua lake, as happened in New Plymouth, clearly weighs on the trust. "God forbid we ever have to do that here in Rotorua," Haumaha said.
The response from the community has given him encouragement. "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," he said. A roster will be drawn up to coordinate the volunteer effort.
Haumaha described the area's lakes as pristine and said they needed to be safeguarded for future generations. He also urged boaties arriving at a ramp to be kind to the volunteers giving up their time to help.
