Sponge set to suck in profits

Next time you exfoliate, spare a thought for a squashy creature living around d'Urville Island, a bunch of dedicated scientists and an emerging New Zealand industry.

In your hand a sea sponge skeleton is a nice-looking bathroom accessory, but in its natural environment spongia manipulatus is a slimy, filter-feeding organism with a long history and great potential in aquaculture.

For the past few years Sean Handley has been assessing whether growing natural, sustainably produced, environmentally friendly sea sponges in the outer Marlborough Sounds is a viable enterprise.

The National Institute of Water and Atmospheric Research (Niwa) scientist says natural sponges, used worldwide for everything from applying cosmetics to bathing, are reputed to last a lot longer than synthetic sponges and to have anti-bacterial qualities.

They have been harvested in the Mediterranean for centuries, resulting in a dramatic decline in numbers.

"Because of that, people are starting to grow them in aquaculture," he said.

"They are quite common on d'Urville so we have been taking half of the parent sponge and leaving the other half behind so they can regrow."

Part of the sponge can be chopped off and the rest of the cells will change roles so the organism stays alive.

At Catherine Cove on d'Urville Island and Croisilles Harbour on the eastern side of Tasman Bay, Niwa is working with mussel farmers to attach propagated sponges to marine farms.

"The sponges eat tiny food particles, including bacteria, and we are investigating whether they could benefit from growing alongside mussels or the oysters," Mr Handley said.

So far the results have been mixed. "At one site some of the sponges doubled in size over eight months so that was quite promising, but some of them shrank to their original size."

Project leader Dr Michelle Kelly says the New Zealand market for bath sponges is small, but the United States and European markets have huge potential.

"To perform well on the international stage, the New Zealand-grown resource must be natural, sustainably produced, environmentally friendly, durable, correctly priced, and of high quality," she said.

"If these requirements are met, there is great potential for a successful boutique industry."

The New Zealand bath sponge had received high praise from overseas companies and Niwa had verbal commitments from German and American companies to buy them, Dr Kelly said.

It was also working with Australian companies.

Niwa held a workshop in Nelson last year to discuss the feasibility of bath-sponge farming with Ngati Koata, Ngati Rarua, Sanford South Island and independent marine farmers.

Dr Kelly said the participants supported sponge aquaculture and were keen to participate in research by providing marine farm space, developing farming methods and collecting sea sponges.

- NZPA

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