Council split on seaweed

Environment Waikato's regional pest management committee is split over how it should respond to possible increased commercial harvesting of the highly invasive Japanese seaweed Undaria pinnatifida.

Maf Biosecurity New Zealand is seeking feedback before the end of the month on whether to allow greater commercial utilisation of undaria now found in many parts of New Zealand, including the Firth of Thames than is permitted under existing regulations.

Undaria is one of the world's top 100 most invasive species.

However, potential commercial market opportunities also exist, and Biosecurity New Zealand appears to be leaning towards freeing up harvest rules.

But at last week's regional pest management committee meeting, members and attending councillors were split three ways on what approach Environment Waikato should recommend in its submission.

Five supported harvesting where undaria was a byproduct of existing operations (such as clearing fouled lines).

Four supported further undaria harvesting in forms such as allowing it to be scraped off rocks in areas where it had become naturalised, while three supported commercial harvesting in areas where undaria was already heavily infested.

Councillor Andra Neeley said there were inevitable conflicts when a market was established for a pest.

"It gets into a really murky area when you give something an economic benefit," she said. "It mitigates against ever getting rid of it."

But councillor Norm Barker said he had spent a lifetime trying to eradicate weeds such as ragwort from his farm.

"Many times I have thought `if only there was value in ragwort'. Here is a weed with value. We should be using it."

The committee resolved council staff should provide a draft submission, based on only harvesting as a byproduct where the seaweed was already present.

- © Fairfax NZ News