Invasive seaweed not quite gone yet

16:00, Mar 28 2014

A multi-agency project to rid Fiordland of an invasive Asian pest has been dealt a blow after a hardy single specimen was found lurking in its waters.

The seaweed undaria, also known as gorse of the sea, was found in Sunday Cove, Breaksea Sound, Fiordland in 2010.

A concerted effort by Environment Southland, Department of Conservation and the Ministry of Agriculture and Fisheries to rid the isolated area of the underwater invader had been largely successful, with no specimens found in the past nine months. However, the latest survey of the area found a single, possibly reproductive plant.

Environment Southland project response manager Derek Richards said while the find was disappointing, it was not the end of the world.

"It's not a game changer, it just means we need to make sure we are being as thorough as possible.

The response to the pest had involved the release of thousands of sea urchins, or kina, which have a natural appetite for the weed, as a biocontrol agent. Mr Richards said the response team was still very happy with how the project had gone. They would look at releasing more kina into the affected area, he said.

"It [the find] shows it is still an issue in there and we just have to work extra hard to make sure we don't miss any in the future." 


The Southland Times