Mātauranga Māori for Rotorua lakes meets New York Times

Lake Rotokākahi or Green Lake, one of four small lakes lying between Lake Rotorua and Lake Tarawera. Photo / File

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A Rotorua iwi organisation has received global attention for its innovative use of indigenous knowledge to transform the water uwhi mats.

Uwhi, woven harakeke (flax) mats, are placed on the lake bed to suffocate aquatic pests and invasive weeds. The mats are being trialled in three of the 14 lakes in TALTS' jurisdiction. And that work has been reported in the New York Times.

When the invasive weeds die it allows for native weeds and kōura (freshwater crayfish) to breed and grow in their place.

William Anaru, the biosecurity manager of the local tribe, Te Arawa, at Lake Rotomā. Photo / Cornell Tukiri, The New York Times

Native weeds, freshwater crayfish, and mussels filter the water and improve the overall quality.

"We are using mātauranga Māori to fix a modern-day problem," says William Anaru, TALT operations manager for biosecurity.

Aquatic pests and weeds have been an ongoing issue for the health of lakes and rivers throughout Aotearoa New Zealand.

Before the pandemic, TALT was sourcing hessian mats internationally to address this issue. Hessian mats are made from the jute plant in Asia and are often used in New Zealand for the laying down of hāngī or as potato sacks.

TALT said it wanted to "trial a sustainable option and create employment for our people", hence the development of the uwhi.

"We wanted to create mahi for our people to fix a problem in our place," Anaru says.

Thirty-two local weavers have been involved in the production of the uwhi, providing employment during the turbulent times of Covid.