A fabled shellfish that nearly vanished

As the passion for toheroa spread into New Zealand’s pakeha (white settler) community, other ways to eat them became popular, with devotees arguing over whether they were best minced up into fritters for frying – with additions like cinnamon or parsley – or turned into a soup celebrating what legendary 1960s TV chef  Graham Kerr called “the rarest food item in the world” in a recipe.

Māori Robyn Boulter shared her toheroa memories in an evocative 2015 film. “My first recollection was going down the beach and seeing all these thousands of holes! We used to go down on our horses, jump off, dig them up and eat them just like that. Raw is beautiful.” She was happy to cook toheroa fritters too. “I have only one recipe. Just toheroa, onion, egg, flour – that’s it.”

Ross reveals the impact of his own debut tasting. “The first one I ate was when I went to the beach with a Māori expert who was showing me how to find them. He cracked one open then and there, and we ate it raw. I was a bit nervous but couldn’t appear squeamish!” he said. “But it was so delicious. And that was first time I really understood why these were so special and so popular.”

Though Māori tribes were known to battle each other for access to particularly abundant toheroa beds – the term for sections of beach where large numbers of toheroa gather together in the sand – the key event in toheroa’s culinary history came when the Prince of Wales (later Edward VIII) had his first taste of luscious green toheroa broth on a 1921 visit to New Zealand. So smitten was he by its distinctive taste that he shattered royal protocol to ask, Oliver Twist-style, if he could have some more.

This hearty expression of royal approval sparked media coverage across the British Empire, and the dish “fit for a king” quickly became a key fixture on New Zealand menus, before spreading across Britain’s globe-spanning dominions. Toheroa soup – exported in gaudily labelled cans – was served at both high-end restaurants and humble diners in Britain, considered a favourite comfort food to combat the winter chill.

The first toheroa cannery was established in the 1890s at Mahuta Gap by Ripiro Beach – New Zealand’s longest stretch of sand – and the 1920s royal thumbs up saw others spring up across the country. From the 1920s to the 1960s, an average of 20 tonnes of toheroa was canned a year. There were dramatic spikes, though – 77 tonnes were put into tins in 1940, for example, partly to supply New Zealand troops heading abroad to fight in World War Two.

There was also an explosion in the number of people heading for New Zealand beaches to dig toheroa for themselves. In the 1920s, the daily limit on toheroa was 50 per person, and the shellfish could be taken for 10 months of the year. From the 1950s, as toheroa numbers dwindled, authorities still allowed an open season of two months, but reduced the individual limit to 20 per day. On one weekend in 1966, an estimated 50,000 people poured onto Ripiro Beach like a hungry whirlwind, pulling an estimated one million toheroa from its sands.

Toheroa stocks began to collapse – something that still angers Māori rights activists like Paturiri Toautu. “For us Māori this kai (food) was very precious. They were an integral part of our food source,” he said. “But then the pakeha realised that serious money could be made from canning the toheroa and selling it overseas. So they built canneries, and within 20 years, our precious taonga was nearly extinct.”

Commercial harvesting was finally banned 50 years ago, and the last “open day”, when people could plunge into the shallow surf to dig for their own taste of seafood heaven, was back in 1993. Now anyone caught harvesting toheroa illegally faces fines up to NZ$20,000 (about £10,300) or community service sentences – though that still doesn’t deter everyone, with the NZ Herald reporting a prosecution as recently as September 2022.

Only local Māori can still legally harvest this treasured form of kai moana (seafood) – and only then for special occasions such as tribal meetings or funerals. Serving toheroa also serves as a savoury manifestation of the key Māori principle of manaakitanga: generosity and hospitality that reflects the host’s status and mana (prestige).

Māori have teamed up with marine biologists to try and restore toheroa numbers. “Māori have always been scientists,” explained Mercier in one of her Science Learning Hub broadcasts. “Our science has allowed us to live, work and thrive in the world for hundreds of years.”

This Māori knowledge of the environment and its myriad forms of life is called mātauranga, and its ancient insights have been appreciated by contemporary scientists for shedding light on some of the mysteries of toheroa life. “Modern science has a surprising lack of knowledge around toheroa biology and ecology,” said Ross.

According to Māori mātauranga, microscopic baby toheroa roam in the water for up to 21 days after birth, before riding the surf foam and onshore winds to get blown into the sand dunes, where they nestle inside a dune grass called pingao (also known as golden sand sedge). After growing inside pingao, when ready to return to the ocean, the toheroa hitch a ride on flowerheads that sea breezes send tumbling from the dunes back down to the water’s edge.

Today, Māori coastal communities share their ecological insights with scientists who, in turn, show them how to carry out precise data gathering to monitor changing amounts of toheroa on different beaches.

A key complement to this research involves educating children about toheroa and the need to change harmful human behaviours. For example, the pakeha love of driving cars on vast beaches like Ripiro may lead to young toheroa being crushed in the sand. 

Māori author Betsy Young has combined toheroa conservation work with a children’s book due to be published later this year. Written with fellow conservationist James Te Tuhi, The Journey of the Little Toheroa will weave together Māori and modern scientific knowledge.

Young told me about joining her first project to enhance toheroa numbers, run by the Māori Women’s Welfare League. “That was the best environment project anyone could have done on the amazing life cycle of the toheroa,” she said. “We started a trust after that in 2005, winning many awards and going to schools to share stories about the pingao and its connection with toheroa.”

While toheroa numbers remain in a state of flux, there are signs this legendary shellfish may be on the way back. “I am always optimistic about the future of the toheroa,” said Young. 

She is echoed by Ross. “They are as abundant as I’ve seen them in 10 years. And there is a huge amount of young,” he said. “So, I’m optimistic that if the environmental conditions are right, the capacity is there for toheroa to recover. The issue is the human element – the need to make big decisions on how we use land.”

BBC.com’s World’s Table “smashes the kitchen ceiling” by changing the way the world thinks about food, through the past, present and future. 

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