25/02/2026
Beneath the surface of our awa and roto lives a quiet taonga many people never notice.
Kākahi, also known in some rohe as torewai or kāeo, are the freshwater mussels unique to Aotearoa. They sit partially buried in sand and mud across our streams and lakes, steadily contributing to the balance of our ecosystems.
They are powerful filter feeders. Each kākahi can filter around a litre of water every hour, drawing water through their bodies and removing fine sediment, algae and microorganisms. While we talk about restoring our waterways, they are already doing the mahi.
With a strong muscular foot, kākahi slowly move, burrow and anchor themselves into the riverbed. In shallow water you can sometimes see the trails of their quiet wanderings etched across the sediment.
Their life cycle is closely connected to native fish. In their early stage, their larvae briefly attach to species such as īnanga and kōkopu before settling into the riverbed to grow. When fish migration is blocked or water quality declines, kākahi populations decline too. They are indicators of mauri.
For generations they were part of mahinga kai, valued as a dependable food source, especially in winter when other resources were scarce. Today they remain a reminder that our freshwater systems are interconnected and living.
If your awa still holds kākahi, protect it. When kākahi thrive, our waterways are stronger. When our waterways are stronger, so are we. ❤️💛❤️
