Far North iwi have joined forces with biosecurity staff to clear a marine invader from some of the country's most significant stretches of coastline.
The Australian sea squirt Pyura praeputialis - usually just called Pyura - is an aggressive invader of rocky shorelines, and was first found at remote Twilight Beach
near Cape Maria van Diemen.
Since then MAF Biosecurity surveys have found Pyura around the Far North coast, including Cape Reinga, North Cape, the Parengarenga Harbour, the Bluff at Ninety Mile Beach, and Tauroa Pt near Ahipara.
Senior marine adviser Katherine Walls said Pyura could smother and displace native green-shell mussels, so Biosecurity was testing the effectiveness of removal techniques.
Another factor was the invader's presence in areas of high value to Maori.
A four-day programme involving iwi, the Northland Regional Council and Department of Conservation started on Monday.
Ms Walls said completely eradicating the well-established pest was not feasible.
"There is, however, such a high level of interest in the local community that we consider there's merit in trying to remove the species from some sites where population numbers are relatively low. This pilot treatment at a couple of sites will tell us whether it's worthwhile attempting to manage Pyura at other places where numbers are low."
Four locals and a marine scientist had been working until yesterday to clear all visible Pyura from the Bluff and Whareana Bay.
They were to remove and bag the sea squirts, then dispose of them far from the sea to avoid re-infestation.
A scientific control trial was being carried out at the same time at the entrance to Parengarenga Harbour, with one area being treated and one left alone to compare results.
The programme will be repeated in six months and its effectiveness evaluated.
