When Andre and Robin LaBonte are not working on coastal restoration projects around Northland, they are caring for their much-loved grass carp.

From their Waipu Cove farm, Andre, 56, and his wife, Robin, 45, nurse little grass carp from tiny hand-sized creatures to nearly 8kg grass-eating monsters, ready to be plucked from their pond and placed inside choked-up lakes, rivers and dams where they will nibble at aquatic plants and unwanted weeds.

The couple are among the country's few university-trained ocean engineers, who have always had an interest in fish farming and preserving the ocean's natural fish supply, and consider weed-eating grass carp among the best pest controllers in the world.


The LaBontes immigrated from Florida 17 years ago after falling in love with New Zealand's natural beauty and open spaces on a holiday. In Florida, they worked as ocean engineers for a company involved with making manmade beaches. They took the ocean data needed to design the beaches.

Soon after arriving in here they bought 15ha with sweeping views of the ocean on the cliff edge just south of Waipu Cove beach.

They have worked on marine projects including restoration of the Mangawhai Harbour and the Matapouri and Pataua coastal erosion investigations.

The chance to farm fish was part of the reason the couple moved to New Zealand.

It took Mr LaBonte years to win consent to keep grass carp, but he persisted with battling red tape to keep the fish because he has dreamed about owning grass carp since he saw them in a pond in the United States.

Last year, 4000 of the couple's fish went to Lake Omapere in Kaikohe to eat weeds that had spoiled the lake's natural habitat.

The LaBontes believe the fish are an organic farmer's best-kept secret. They are easy to keep, feeding on daily trailer-loads of lawn clippings.

And they are in demand from local farmers, who call nearly once a week asking to use the fish for weed control.

The LaBontes also sell their fish to an Asian restaurant in Auckland.

But Mr LaBonte says that although they are easy to keep and good weed controllers, the fish, which live in 60 countries around the world, have a bad reputation.

Trying to get permission to keep them has been a nightmare, he says. It is most of the reason the LaBontes' grass carp farm is one of only three in the country.

The fish have a similar name to one of New Zealand's most unwanted fish - the highly productive native-fish-eating Japanese koi carp.

He suspects this is why officials are so cautious about letting people farm the grass carp, even though he says the two species are completely different.


* Grass carp feed almost continuously when water temperatures are between 21C and 26C.

* Under ideal conditions they can eat 2-3 times their body weight in a day.

* Grass carp can grow to 5kg-plus in the first year and ultimately to more than 20kg.

* Contrary to popular opinion, adult grass carp do not eat sport fish or compete with them for food.

* Once a grass carp reaches 15cm, it will feed almost exclusively on plant matter.