In an article published at the weekend, Renton reports on Hagen Stehr, who arrived in Australia 50 years ago as a tuna fisherman. Nowadays he's ranching the fish, because that's a more sustainable means of harvesting them.
"Look at agriculture - we're running out of land, we're running out of water. Look how the prices of food are going up. In the future, people's protein is going to have to come out of the sea - it's all we have left," he says.
And Renton says that if money talks, then Stehr deserves to be taken seriously.
"In the future, people's protein is going to have to come out of the sea - it's all we have left"
Hagen Stehr, Tuna Fish Rancher
Every Thursday he and his fishing friends meet in a café in Port Lincoln, the small fishing community near Adelaide on Australia's south coast that they have made the country's richest town. When the four members of Stehr's 'Cappuccino Club' gather, he says, there's more than a billion Australian dollars (nearly half a billion pounds) at the café table.
They made the money from killing and selling bluefin tuna. A single one of these beasts can cost as much as a Volvo (in January a 276kg bluefin sold for £28,000 in Tokyo) because its belly meat provides the sweetest sashimi of all. The bluefin is, as a result, one of the world's most endangered food animals - not that that's stopping the fishing. Stehr and his friends, who own the majority of Australia's tuna fishing licences, made their first fortunes catching tuna in the normal way, by hook and net. But in the early Nineties, worried by ever tighter quotas on the disappearing bluefins, the Cappuccino Club pioneered the 'ranching' of the fish.
This was one of the most brilliant ideas in the history of industrial fishing, and it has now spread all over the world. What Stehr and his friends do is catch young bluefin. Since quotas limit the tonnage of fish caught, this allows them to take more. They then corral them in vast purse-shaped nets that are hauled by tugboat around the southern ocean at less than one mile an hour for eight months. The ranchers, marine cowboys, battle storms and fend off sharks, and all the time they feed the growing tuna.
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