Te Arawa descendants are leaving nothing to chance to protect their taonga species from invasive freshwater pests

William Anaru, biosecurity manager for Te Arawa Lakes Trust.
William Anaru, biosecurity manager for Te Arawa Lakes Trust. Photo credit: Supplied / Te Arawa Lakes Trust.

By Maioha Panapa, Te Rito Journalism cadet

A group of Iwi entities involved in an experimental control harvest trial has discovered 125 kg of Gold Clams along the Waikato River.

The invasive clams were first found in April, and originate from Asia.

The Iwi entities involved are Waikato-Tainui, Tūwharetoa, Ngāti Haua, Te Arawa River Iwi, Raukawa, Maniapoto, Ngāti Koroki Kahukura and the Waikato River Authority.

William Anaru (Te Arawa and Te Whānau a Apanui ) is the biosecurity manager for Te Arawa Lakes Trust and says that the invasive clams have not made their way down to Rotorua yet.

“As soon as we found out about them we tried to figure out how we could shut down or restrict access to the lakes. There’s no way we could do it.

“So straight away with the Regional council, our dive team jumped in the water and we did surveillance around all the boat ramps, most popular lakes and we didn't find any.

“NIWA came to do DNA samples and visual inspections and they didn’t find any yet.

“So we don't have them in our rohe yet.”

The Ministry of Primary Industries says the clams are hermaphrodites, which means they’re both male and female and can reproduce 400 fully formed clams a day (70,000 a year).

The Gold Clams, also known as Asian clams, can feed on plankton which is what most native species survive on.

Some of the 125kg gold clams retrieved by Waikato River Authority workers from the Waikato River.
Some of the 125kg gold clams retrieved by Waikato River Authority workers from the Waikato River. Photo credit: Supplied / Waikato River Authority Trust.

Anaru says their main concern is the protection of their own native, or taonga, species  that will be harmed if the clams are found in Te Arawa lakes.

“What I’m really worried about with this Gold Clam is how it’s going to displace our taonga species, like Kākahi.

“These clams will probably invade the same habitat that the Kākahi are living in and displace them.

“The Kākahi will probably die off because the clams can smother them.

“That’s probably something that we might see, but we don’t want to test that theory to find out.”

Anaru says in the majority of the Te Arawa lakes certain taonga species are doing better than others, but adding another factor to their environment may see the extinction of some.

“We’ve got plastic pollution, human waste, climate change, pests.

“Adding another pest to the ring is gonna make things harder for them all.

Te Arawa Lakes Trust is working with the Iwi Communication Collective to begin a campaign identifying the health & safety steps when fishing/diving from one waterway to another.

Anaru says this is an Iwi approach to help warn people about the clams, especially when crossing between waterways.

“Say you're fishing in Karapiro and you've got your waiters on or whatever, you could have a small baby clam attach itself to the joints in your waiters.

“Then you could bring it back home, they could fall off and then, you know, we've got the problem over here.

“Everyone is welcome to come to our lakes. Just as long as you make sure to check, clean and dry.”

Anaru encourages that if anyone comes across these clams to not eat them.

“What these clams do is that they’ve taken the toxins that are in the water and they hold on to them.

“So if you eat them, you’re eating some pretty nasty things.

“But when you eat something, you give it value. We don’t really want these things to have any value in our Wai.”

Public Interest Journalism funded through NZ On Air.

Te Arawa descendants are leaving nothing to chance to protect their taonga species from invasive freshwater pests