A new opportunity for commercial whitebait production.
After 10 years of researching commercial farming of whitebait, it is set to become a reality in New Zealand. The breakthrough has come on the back of six years of perfecting the breeding of the giant kōkopu in captivity.
Whitebait are the juvenile stages of five species of New Zealand’s native fish, including the giant kōkopu. They belong to the Galaxiidae family. Although galaxiid species are found in many places in the Southern Hemisphere, the giant, shortjaw and banded kōkopu only exist in New Zealand. Our galaxiids are generally nocturnal and very good at hiding.
The small fish caught each spring by whitebaiters all around the country are the juveniles. Those that escape the whitebait net grow into dark, slender adults with delicate gold spots, lines and rings covering the body.
The main breeding season for our galaxiids is autumn. Kōkopu lay their eggs on leaf litter and submerged forest plants in streamside vegetation. The eggs can stay out of water for several weeks, as long as there is good plant cover to keep them moist. They hatch when re-immersed, either by spring tides or floods. The larvae then float out to sea where they live and grow over winter, migrating back upstream as whitebait in spring.
Whitebait are in decline, mostly due to a lack of clean, healthy rivers and streams for the adult fish. Barriers such as dams and overhanging culverts block migrating whitebait from reaching what clean streams remain. Introduced fish compete for habitat and prey on our native species and introduced plants clog up the places where whitebait live.
Whitebait are the only native species that can be legally harvested and sold outside of the Crown’s Quota Management System, consequently a lot of that trade is unregulated.
While kōkopu are only one of several fish species that make up whitebait, aquaculturist Paul Decker says they are the tastiest. Researchers at the former Mahurangi Technical Institute have been working with all five species but ended up focusing on the giant kōkopu.
Paul says the work they are doing in breeding the fish in captivity is preserving the fishery. "I foresee a day when commercial whitebaiting will have to cease. Quite frankly farming is going to be the saviour of the species."
Understanding how the fish breed in the wild was a big part of their success. New Zealand Premium Whitebait now has a large number of adults in tanks in the industrial area of Warkworth. In the hatchery the adults are ‘stripped’ of their eggs and milt, the two are combined and the whitebait eggs form.
The successful breeding in captivity by Paul Decker and chief scientist Dr. Tagried Kurwie at New Zealand Premium Whitebait is seen as a highly appealing commercial business opportunity.
NZ Premium Whitebait was formed in 2014 to undertake the commercial development of whitebait farming. The company’s CEO is Jeremy Gardiner. Jeremy says whitebait fishing in the wild is not sustainable long term. He says farming ensures that we can control quality of the product, consistently deliver a fresh product and harvest at the point of premium quality. The company can produce whitebait consistently all year round.
The company produced its first commercial harvest of about one tonne in 2016. Sales in 2016 were limited by the small production, with about half going to premium local restaurants and the remainder sold in limited amounts to supermarkets.
The next step is to build a larger facility which is expected to help boost production to between 20 to 30 tonnes over the next couple of years.
"The nature of the fish is the bigger they get, the more eggs they produce. We will have more eggs than we can do anything with for quite some time," he said.
Shareholders of NZ Premium Whitebait include Ka Ora, a company whose owners include the Gardiners. They believe it is the beginning of a really big aquaculture industry in NZ.