What do castaways actually eat?

I have often fantasised about how I would survive on a desert island. Because I am a greedy person, most of these fantasies revolve around what I would eat. I have a dream sequence I like to play in my head in which I am performing food-related acts of valour. I picture myself catching a fish with my bare hands and then roasting that fish, or grappling in the mud with a big pig. Sometimes I eat alone, gazing pensively at my fire, and sometimes I feed a host of fellow castaways, who look at me adoringly and stoke my fire and clap.

My rose-tinted view of castaway dining is partly inspired by Robinson Crusoe, Daniel Defoe’s 1719 novel about a man who is shipwrecked for 28 years on a tropical island and dines remarkably well. A lazy man before his shipwreck, the need to hunt brings out something heroic in Crusoe. This is probably where I got the idea that I could, in extremis, fight a pig. But in the unlikely event that I am ever stranded, I worry that I will reveal myself for who I really am. Uncoordinated and sneaky. The kind of person who deliberately eats more than her fair share of sharing plates.

Last week, I travelled to the leafy London suburb of High Barnet to interview Douglas Robertson, whose name comes up when you google “real-life Robinson Crusoes”. In 1972, Robertson was sailing around the world with his mother, father, twin brothers and a hitchhiker when their yacht was attacked by a pod of killer whales. The family were stranded for 38 days in the middle of the Pacific Ocean, surviving mainly on raw turtles. Robertson was just 18 years old.

I tracked Robertson down by ringing him at work — he runs an accountancy business — and my first thought, when he came to the door, was that he looked a lot more like an accountant than a former castaway. Grey-haired and twinkly eyed, he led me into a sitting room crammed with family photographs. We sat at his dining table, which he told me, disconcertingly, was roughly the same size as the dinghy in which he lived with five other people for weeks.

When I mentioned Crusoe, Robertson told me his castaway mealtimes were a lot less idyllic. Turtle blood, which the family referred to as “soup”, became a staple. They sliced up raw turtle meat very thin, like steak tartare, and sprinkled it into the mixture as a garnish. “We had this gory red liquid, with bits of yellow fat floating round it,” Robertson said. “To us, that looked very beautiful.” When water supplies ran dangerously low, his mother Lyn, who was a nurse, came up with an ingenious solution. There was rain water at the bottom of the dinghy, but it would poison the family if they drank it because it was polluted by bits of old fish. Lyn worked out that the water could be safely absorbed through the rectal membrane. Robertson whittled a tube out of the rung of the dinghy’s step ladder, and Lyn gave everyone in the family an enema of blood and rain.

The history of real-life castaway dining is rife with similarly gruesome tactics. A decade ago, a fisherman from El Salvador called José Salvador Alvarenga survived 438 days adrift with just one other shipmate. His diet included whole uncooked seagulls, which he caught by lying very still and waiting for a bird to land, at which point he would pull it down by its legs. Instead of killing the bird outright, he would break its wing so it was unable to fly away.

When Alvarenga finally washed up on land he was alone; his shipmate died at sea. A year later, the man’s family tried to sue Alvarenga for $1mn, claiming that he had eaten their relative. Alvarenga denies eating human flesh, but many others have. Cannibalism has a rich history among the stranded, which makes me think that the experience of being cast away might not be so character-building after all. Known colloquially in the 19th century as the “custom of the sea”, sailors would decide which one of them was going to die by drawing lots (the one who drew the short straw was dinner).

Robertson told me that cannibalism was discussed perfectly openly among his family. “We made a pact early on that we would die together, that we wouldn’t eat each other,” Robertson said, rather matter-of-factly, adding that Robin, the hitchhiker, had particular cause for concern because he wasn’t a family member. “I don’t know whether he ever believed us. He was always worried.”

Towards the end of the interview, I asked Robertson which of the two of us would get eaten, if we were in a hypothetical 19th-century shipwreck. “If it was just me and you, I’m afraid you would be eaten,” he said, giving me a cheeky look across his dinghy-sized table. “You would be more of a burden.”

Today, anyone curious about their survival skills can test them out vicariously, through the medium of reality TV. One of the most addictive examples of the genre is Man vs Wild, the Channel 4 programme in which Bear Grylls, an Eton-educated ex-SAS officer, strands himself in various remote locations and then attempts to survive. Grylls teaches viewers how to do things like drink urine out of a snake and then wear that snake as a scarf. In one clip, which has been viewed 1.9mn times on YouTube, Grylls recreates the Robertson family enema. You watch as he lies on his back like a crab and funnels dirty water into his bottom. He screams. Part of the appeal of this video is that it is framed as a “how to”. You watch it on your sofa and take notes, as though you might one day be compelled to do the same.

A few days after my meeting with Robertson, I managed to snag an interview with Grylls. He started by telling me that many of us live our lives stuck in a “comfort pit”, his term for the deadening ease of modern life. We are drawn to castaway stories because they awaken something “primal” in us, he said. “We are hard-wired to thrive in danger. You can’t go millions of years with that deeply embedded in the psyche and then go ooh! I’m not going to feel that any more.”

Bear Grylls spoke to me on the phone, using his AirPods, but told me he was in a park, barefoot, tucked away behind some foliage

Grylls spoke to me on the phone, using his AirPods, but told me he was in a park, barefoot, tucked away behind some foliage. He was doing a series of press calls, but liked to do them on the move, with his “feet on the ground”. I asked him about the role food plays on his show, but he spoke to me instead about his diet. “I try to eat in everyday life as I eat in the wild,” he said. He never eats vegetables because he doesn’t think humans were designed to eat vegetables. Instead, his diet includes two or three steaks a day and eight eggs.

After our chat, I went on a walk (with shoes on) and thought about his diet, which had made me feel queasy, but also strangely jealous. My life revolves around what I’m going to have for dinner, but it seems that Grylls has evolved past dinner. I thought about being cast away and wondered whether the real fantasy was to evolve past pleasure altogether. To become the kind of person who is perfectly happy to drink urine out of a snake.

Later that week, I drove to a luxury hotel in East Sussex to attend a course run by the Bear Grylls Survival Academy. I had been invited to join hotel staff as they tested out the academy’s team-building activities, which include axe-throwing and eating scorpions out of a bowl. The hotel plans to sell the courses to corporate groups, but they also want to market the activities to guests as a kind of leisure activity, something you might buy in place of a spa day. (I didn’t pay to join the training session, but did pay for a later private tutorial.)

I joined a group of 12 women on the hotel’s lawn and we began to cosplay being stranded. We rubbed mud on our faces, and then the instructors — two energetic men called Kirsten and Ed — taught us how to build an “SOS” sign on the ground out of twigs. About halfway through, we were asked to act out a scenario in which one of us had been injured. The “casualty” was allowed to lie down with a bandage on her head while the rest of us fumbled around desperately in the grass, trying to build a stretcher. Suddenly, Kirsten lit a purple flare and started running away from us, screaming that the “helicopter is coming!” We hoisted the casualty on to the stretcher and ran around the lawn in a circle. At the end of the session we did a “gross eat challenge”, and I ate a raw tarantula, which was crunchy and tasted a bit like soil.

After the course, Kirsten and Ed talked me through the more intensive experiences you can purchase at Grylls’ academy — like the 24-hour Primal Survival Adventure, which costs £328 per person and includes a lesson on how to kill your dinner. Participants learn how to lay traps, but this is really just a bit of theatre. The academy pre-buys hares and presents them, already dead, to the guests. As he told me this, Kirsten mimed the correct technique for swinging a live hare by its feet to calm it down and then whacking it with a stick.

As I watched Kirsten swing his imaginary hare, I thought about the motivations of this customer who chooses to make-believe that she is starving and lost in the wild. The new indulgence seems to be to forgo indulgence altogether. To simplify your relationship with mealtimes for a brief while. To emulate Grylls and convert food from a pleasure to a fuel.

But it’s strange, because for real-life castaways, the opposite seems to be true. Revelling in the pleasure of food, even if it is truly horrid or only imaginary, is what many credit with giving them the will to survive. When Alvarenga finally washed up on dry land, he told reporters that he had got through those interminable 438 days by lying on the floor of his boat, looking up at the sky and visualising elaborate dinner menus: oranges and tacos and chicken and tortillas.

Robertson told me something similar. Every day on the boat, the family would play a game during which they planned meals for a fantasy café. Everyone would put an elastic band in their mouths and chew on it, to create the illusion that they were eating. Then they spent hours salivating over the day’s dishes, imagining steak and chips and fresh melon salad and plates of beef stew. As a food-obsessed person, I find these stories reassuring. Fantasising about food, it turns out, is a useful survival skill. If you are landlocked, your ambition might be to give up all indulgence. But if you are ever truly cast away, indulgence could be the thing that keeps you alive.

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