Considered an exotic delicacy in many parts of the world, paua meat is an important part of New Zealand’s seafood exports. But an even more select market covets the jewellery created from the animals’ iridescent shells – and the pearls they cultivate.
In addition to its brooding beauty, the Marlborough Sounds is renowned for its mussel and salmon farms. Less well-known is that it’s also home to a small but exclusive paua-farming industry.
Among the players is Arapawa Seafarms – breeding the animals not so much for their meat but for their shells and pearls. It also cultivates the paua for commercial reseeding – and it played a vital role restocking the devastated coastline after the 2016 Kaikoura earthquake.
As the name suggests, the farm’s located on Arapawa – the Sounds’ easternmost island – it lies alongside the route sailed by the Cook Strait ferries. The farm’s owned by Mike and Antonia Radon who launched their enterprise some 20 years ago with, they confess, a very different business plan.
“We began farming the paua for their meat – with just four breeding tanks,” says Antonia. “But we eventually realised that shells and pearls held more promise. So we switched tack – we got into the jewellery business by accident.” Today the infrastructure has expanded to 400 tanks – each about a metre square – all part of a complex but sophisticated operation.
Shaping the couple’s focus is the jewellery industry’s growing demand not only for the animal’s distinctively-coloured shells, but also for the unique pearls they produce. Renowned for their lustrous blue colour, these ‘Mabe’ pearls stand in exclusive contrast to their more common white or black cousins cultivated elsewhere in the world.
The pearls’ colour is a function of the species. While New Zealand has three endemic species of paua, it is the largest – the black-footed animal (haliotis iris – ‘rainbow sea ear’ in Latin) – that’s used for pearl cultivation. Haliotis iris is one of the world’s most primitive molluscs – evolution has left it largely unchanged for half a billion years. The survival rate from egg to adult paua is one in 20 million.
So it takes an exceptionally rare, ancient creature – and a helluva lot of luck – to deliver an ultra-exclusive pearl.
Farming
Ground Zero at the Arapawa farm is the hatchery. “Male and female paua release millions of sperm and eggs in the spawning season,” says Antonia. “We manage the fertilisation process on a weekly basis. When the eggs hatch the tiny larvae live and grow in the nursery tanks – around 20,000 per tank. As they grow, we separate them into other, more sparsely-populated tanks.”
She points out that in the wild the survival rate is very low because relatively few larvae find a suitable ‘foothold’ – and they’re also decimated by predators.
After spawning and fertilisation, the farm typically has some four million larvae swimming in 20 large tanks. As part of an industry initiative many of these are released into the wild after about eight months to help reseed the region’s paua stocks.
Pearls
“Cultivating Mabe pearls,” says Mike, “uses the same technique employed by pearl growers all over the world. After four years of growth, we introduce an ‘insert’ into selected paua – between the flesh and the shell. The insert is a ‘mould’ – a small, rounded piece of Mabe. The paua lays ‘shell’ over the mould – it helps to form the pearl’s shape.”
Paua, he adds, are haemophiliacs and bleed easily, so introducing an insert is a very delicate operation. After the process the paua are initially placed into a recovery tank and later transferred to ‘growing’ tanks. Pearls are ready for harvest after three to four years.
Very few of the pearls actually make it to the jeweller’s bench – roughly 5-10 from 50. Not all inserts are successful, and the pearls that are produced are culled in the final grading process – size and lustre are key factors.
Unlike most other cultured pearls, says Mike, these Mabe pearls are completely natural – “we don’t use bleaching and don’t add any colours or dyes. They have to be perfect. We are definitely a boutique operation. Consider that global pearl production is about 43 tonnes a year – we do one kilogram. So, we’re a very small player, but our pearls are very exclusive.”
Shells
Identifying paua shells for jewellery is equally selective. While the swirling colours of the black-foot paua’s shell are unlike any found elsewhere in the world, some shells are better than others.
Finding the right stuff is a family affair. Antonia and two of the couple’s children dive for the mature paua while Mike inspects the harvest. “Only 10 to 25 percent of the shells make it based on colour, pattern and lustre. Animals with lacklustre shells end up in local restaurants or are sold for export.”
Most of the pearls and shells are sold to local jewellers, and while many of the finished pieces are purchased locally, online buying has given impetus to a growing international market.
Reseeding
Like all commercial paua operations, says Mike, “we operate under a quota system. It works well and following the industry’s sustainability and replenishment initiatives over the years the paua beds are now looking really good – in fact they’re the best they’ve been since we bought our license 25 years ago. Back then a good diver would catch 200kg of paua a day. Now it’s more like 300 to 500kg a day – and they’re much bigger.”
Much of Arapawa Seafarms’ activities have been geared to reseeding the region’s coastline – particularly after the 2016 Kaikoura earthquake which elevated the seabed by up to six metres. This exposed and destroyed millions of paua but five years later, things are looking promising.
Paua habitat
Paua are more abundant in the lower North Island and the South Island (where it’s colder) and munch on seaweed. Crabs, lobsters, octopi, starfish and fish munch on paua.
The fishery is managed by quotas, with restrictions on size and harvesting method – a minimum shell length of 125mm and free-diving. No tanks.
Most of New Zealand’s exported paua meat is shucked and canned for shipping, though live export is becoming more popular. According to Statistics New Zealand, the total asset value of New Zealand’s paua resource managed under the QMS (as at 2003) was $330 million, with the Chatham Islands having the highest regional value ($75 million).
