How vibrators are helping Kiwi mussels breed on cue

Scientists have found an unusual way to make greenshell mussels breed in captivity, and their efforts could be a big win for the New Zealand economy.

Warm baths and vibrating devices are two of the methods found to make the popular seafood breed on cue.

Shellfish Production and Technology New Zealand (SPAT) boss and scientist Rodney Roberts says it took years of experimentation in Nelson for the mussels to give up their secrets.

"We finally settled on a combination of light, temperature and small vibrations that seems to really get the mussels going, encouraging them to produce maximum quantities of sperm and eggs."

Mr Roberts says while the process sounds funny, their efforts could be worth up to $200 million a year.

"Normally these mussels breed in the wild and we wait for their babies, known as spat, to wash up on beaches attached to seaweed or land on catch ropes. That made life difficult for New Zealand mussel farmers, who had to cross their fingers and hope they would have enough spat for their farms from year to year.

"We are now able to produce billions of mussel eggs each month."

Chief executive of Aquaculture New Zealand Gary Hooper says it's big news for the industry.

"New Zealand mussels are already world-famous, but the hatchery unlocks a new level of innovation to take our industry to another level."

That next level could include using mussels for more than just cooking, turning the seafood into nutraceutical products.

Hatchery mussels are at harvest size now in the Marlborough Sounds, and close to 500 tonnes of them will be harvested over the coming months.