Shimmering with an opal shine: New Zealand's unique blue pearls face threat of warming seas

Roger Beattie was diving off the Chatham Islands, about 800km east of New Zealand, when he saw his first pāua pearl. Beattie was familiar with pāua, the Māori word for abalone, and their iridescent shells of shimmering purples and greens. But the pearl that had formed inside was unlike anything he had ever seen, gleaming with layers of the pāua's natural colours.
'I just thought 'heck, that would make amazing jewellery,'' Beattie says.
That was in the early 1990s, and Beattie soon started experimenting ways of farming pāua, and creating pearls in the shell. A decade later, he began selling the so-called blue pearls commercially.
Now, a small industry exists in New Zealand cultivating the unique gems. They are rare, with only a handful of companies running farms, each producing only a few thousand pāua pearls each year. But the delicate operations are being made more complicated as changing conditions and warming seas alter the environments pāua need to survive.
'Warm waters cause physiological stress to the pāua,' says Shawn Gerrity, an ecologist at the University of Canterbury who has studied the pāua.
There are four species of pāua endemic to New Zealand. The blackfoot pāua is the biggest species, known for its vibrant shell and succulent flesh. All cultivated pāua pearls come from the blackfoot pāua. The pearls appear shades of blue, turquoise, purple and green.
'Only this abalone, in this water, produces such an unusual colour of pearl,' says Jacek Pawlowski, a jeweller in Akaroa, a seaside town southeast of Christchurch on New Zealand's South Island. He has worked with the pearls for the last 25 years.
'They have that rainbow, opal shine, no pearl is exactly the same,' Pawlowski says.
Many of the world's pearls come from freshwater mussels in China, while more valuable Akoya pearls primarily come from Japan. Black and golden 'South Sea' pearls are cultivated in Australia and around the Pacific.
In New Zealand, making farmed pāua pearls is delicate and labour-intensive. As juveniles, pāua are taken out of the water, where their flesh is pried up and a small implant placed under their shell for a pearl to form on. If their soft bodies are nicked, the pāua will bleed to death, so the process must be gentle. Only one in five pāua will create a jewellery-grade gem, Beattie says.
Each mollusc needs to be fed vast quantities of kelp and live in water about 16 degrees for the three to four years it takes for a pearl to form.
To keep the pāua cool, Beattie's farm is towards the mouth of Akaroa Harbour, with colder water from the open ocean. Arapawa Pearls, in the Marlborough Sounds at the top of the South Island, keeps its pāua in tanks to create a constant temperature.
But rising ocean temperatures pose a threat to their survival. Sea surface temperatures around New Zealand have increased 0.16 to 0.26C per decade since 1982, according to official statistics. Marine heatwaves have dramatically increased in frequency around New Zealand, with a particularly severe event in 2017/18 causing thousands of sea creatures to die.
Increased marine temperatures have caused mass die-offs of abalone species in other areas of the world, like California, where warming water has reduced abalone's access to food and sped up the transmission of a withering disease.
Beattie has had an algal bloom – which is more likely in warm water – kill a harvest of pāua by depriving them of oxygen.
Gerrity says marine heatwaves 'destroy habitats'.
'When kelp is degraded, sea urchins survive, and it's hard to get pāua back,' he says.
Gerrity has researched the recovery of pāua in Kaikōura, on the north-east coast of the South Island, where thousands of pāua died after the sea floor was lifted six metres in a 2016 earthquake. Nine years later, with careful management, the population is healthy again. It is a model for what could happen if a heatwave caused similar pāua deaths, but there's still a lot of risk.
Dr Norman Ragg, senior shellfish scientist at science organisation Cawthron Institute, says pāua are a 'really interesting quirk of nature', that have remained unchanged for millennia. While New Zealand's populations are still healthy, there is no room for complacency.
'There are a lot of bad news stories about abalone around the world – they are a large, tasty, shallow-water, easy-to-catch sea snail that breeds and grows slowly and that puts a lot of burden of responsibility back on to [New Zealand].'
Ragg believes cultivating blue pearls could go some way to bolstering appreciation for pāua and securing its future in the face of climate change.
Looking over his Akaroa shellfish farm, Beattie says he will continue to 'work with nature' to ensure the pāua and their pearls continue to thrive.
'It's almost impossible to improve on what nature makes. The pāua have to be not just healthy, but happy,' he says.

Try Our AI Features

Explore what Daily8 AI can do for you:

Learn with AIFact CheckingText to SpeechAI Summary

Related Articles

Reuters

a day ago

• Reuters

New Zealand PM Luxon meets China's Xi Jinping

June 20 (Reuters) - New Zealand Prime Minister Christopher Luxon said on Friday he and China's President Xi Jinping discussed the role of business, education and science to help boost relations between the two countries. "I raised the importance to New Zealand of the international rules-based system, as well as the key role that China can play in helping to resolve global challenges," Luxon said in a statement after meeting Xi Jinping in Beijing.

The Independent

2 days ago

• The Independent

Another country approves use of ‘magic mushrooms' to treat depression

New Zealand has approved the restricted medicinal use of psilocybin, a hallucinogen found in " magic mushrooms." The approval is specifically for patients diagnosed with treatment-resistant depression. Only one psychiatrist, Professor Cameron Lacey, who was behind the first clinical trials of psilocybin, is authorised to prescribe it under strict reporting and record-keeping requirements. Associate Minister of Health David Seymour hailed the policy change as a "real breakthrough" for individuals who have exhausted other treatment options. New Zealand joins other regions, including Australia, Switzerland, Oregon, and Colorado, in allowing some form of legal or restricted access to psilocybin for medical purposes.

Daily Mail​

2 days ago

• Daily Mail​

NASA warns of potential blackouts amid solar flare

The eruption unleashed a burst of ionizing radiation, magnetic energy and heat capable of interfering with technology on Earth. Dr Tamitha Skov, an independent space weather physicist, said the flare's impact was strongest in the western hemisphere, affecting areas including the US West Coast, Alaska , eastern Russia , the Asia-Pacific region and potentially New Zealand . Almost immediately, the flare triggered a shortwave radio blackout over the Pacific Ocean, with ham radio operators in Hawaii reporting sudden signal loss. NASA and other space weather agencies are now closely monitoring sunspot region 4114, the source of the flare. Sunspots are cooler than other parts of the surface. Sunsport 4114 is expected to remain active in the coming days, and scientists warn that another major flare could erupt as soon as today. 'Another flare may be in the offing today. Sunspot 4114 is large and unstable, with a 'delta-class' magnetic field that harbors energy for strong explosions,' the team at shared. A delta-class magnetic field is like a pressure cooker of magnetic energy on the sun, and it is often a warning sign that a big solar flare is to come. Officials said in a Wednesday update that the solar flare likely came with a huge burst of charged solar particles, known as a coronal mass ejection (CME), which will take about 15 to 72 hours to reach Earth. A G1 geomagnetic storm watch has been issued for Friday, which is the least powerful on the scale of five. However, it has the potential to cause minor fluctuations in power grids, slight impacts on satellite operations and make the aurora borealis visible at high latitudes. Results showed power grids failed, blackouts were triggered and communication broke down across the US. The exercise ran four simulations of geomagnetic storms of different severities. One scenario included a 'solar superstorm', strong enough to cause an 'internet apocalypse,' resulting in power grid disruptions across the entire US, with the eastern seaboard experiencing blackouts, which lasted for weeks. Not only were power grids impacted, but railways and pipelines were also knocked offline, causing mass disruptions of travel and dramatic price increases of gas. Scientists are now calling for a whole-of-government planning approach, arguing it will be critical for protecting America from cosmic disaster. That would include deploying more satellites to monitor space weather, enhancing real-time data collection to improve forecasting models and providing earlier warnings.