Mahurangi Matters covers the fight against Caulerpa

Thanks to Mahurangi Matters for helping us raise awareness of this urgent issue and the work being done to protect New Zealand’s marine ecosystems.

We’re excited to share that Commercial Dive Specialists was recently featured in Mahurangi Matters, with a deep dive into our work combatting the invasive seaweed Caulerpa using our custom-designed treatment chamber, Rehabitat.

The article highlights the ongoing trials of Rehabitat in the Bay of Islands, where CDS Managing Director Brook McRae shared how the results are “exceeding all expectations.” Brook explains that the system is delivering a far more targeted, less environmentally damaging treatment than traditional methods like dredging or benthic mats.

“It’s killing Caulerpa with much less chlorine than we thought,” Brook told the publication, “which means we can treat more ground than we imagined — and the sea water recovers quickly.”

Rehabitat is a floating treatment chamber that moves along the seabed, pumping a controlled dose of chlorinated water into an enclosed area. The chlorine is later extracted before being released back into the ocean, helping to prevent both regrowth and environmental impact. CDS is the only company in the country trialling this sealed chamber technology, which is now being supported as part of a $10 million innovation investment by the Ministry for Primary Industries (MPI).

The article also touches on the scale-up potential of Rehabitat, with Brook noting that a small three-person crew could achieve the work of 100 diver-based dredging operations in a single day — a game changer for marine pest eradication.

While Caulerpa remains the current focus, Brook also shared that Rehabitat could be adapted for other invasive marine species in future.

Read more here on how Rehabitat targets Caulerpa with low chlorine dosing.

You can read the full article by signing up for a free account at Mahurangi Matters.