Survivor's Edge

Adrift in the ocean without food or water, some people last only a few hours. Others endure for weeks, even months. Is it chance —or are some built for extreme survival?

By Jane Bosveld
Jul 30, 2007 5:00 AMJul 12, 2023 3:42 PM


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As they climbed on board the 26-foot shark-fishing boat, Jesús Eduardo Vidaña, Salvador Ordóñez, and Lucio Rendón probably knew they were breaking the law. In Mexico, shark fishing requires a permit, and they hadn’t asked the owner of the boat, Señor Juan, if he had one. But they didn’t care—they needed the money. Later that night, they may have had second thoughts. A storm had rolled in, and their fishing line had broken.

It would cost the fishermen three years’ salary to replace the line, so they spent the next two days searching the water for it. But then the engine sputtered and stopped. They had run out of gas. The wind was still blowing fiercely, and the men knew what this meant. Señor Juan was too poor to have a radio to call for help. If another boat didn’t happen by, they would be carried away from Mexico, farther and farther into the Pacific. If they survived the sea, if no rogue wave took them under, they would soon run out of freshwater and food.

If tempers flared that night on the shark boat, the three fishermen don’t mention it when they tell their story later. Instead they talk of how for the next nine months and nine days they drifted across the Pacific Ocean all the way to the Marshall Islands, where a Taiwanese fishing trawler found them. They tell how they caught fish and birds and drank rainwater to survive, and how they read the Bible and sang to keep their spirits up. They say Señor Juan and the fisherman they knew only as El Farsero—“the trickster”—died during the ordeal because they couldn’t stomach eating raw fish and had vomited. Maybe they’d both gotten sick.

But there is some skepticism about their story. At the press conference the fishermen gave last August after they returned to Mexico from the Marshall Islands, reporters asked them if they had really been running drugs, not fishing for sharks. Had they killed Señor Juan and El Farsero and eaten them? The fishermen shook their heads at the accusations. Lucio Rendón said, “To those who don’t believe us, all I can say is that I hope what happened to us never happens to you.”

A film company called Ezekiel 22 Productions has bought the rights to the men’s story. The ordeal is certainly the stuff that movies are made of, but the nine-month saga is also a fascinating medical story: How is it possible to survive adrift on the ocean for so long without stores of food and water? Why did these three fishermen survive when the odds were so clearly against them? According to Claude Piantadosi, a medical expert in the biology of survival, the answer has little to do with desire. “The most important human factor for survival at sea is knowledge: first of the environment and second of the basic principles of human physiology,” Piantadosi explains. “Whether someone lives through extreme exposure can be boiled down to a few physical and biological factors.”

Lost in Warm Latitudes

To be lost at sea is to be in physiological jeopardy. The human body needs a regular intake of freshwater and food, and it needs to be warm. The sea is a threat on all three fronts. Severe sunburn is yet another potentially fatal concern.

Salt water wreaks havoc on human skin, causing boils and sores that plague castaways after only a day or two. And the unrelenting tossing of the waves can lead to seasickness. For a shipwreck survivor deprived of water and food, episodes of vomiting can be as lethal as a shark attack. As the mountaineer and physician Kenneth Kamler explains, vomiting “deprives the body of food, water, and electrolytes—minerals like sodium, potassium, and magnesium that are critical for nerves and other body tissues. Seasickness increases energy demand—vomiting takes strength but decreases energy supply.” It weakens and dehydrates whomever it afflicts, sapping the body of the ability to function and fatiguing the mind.

But cold water is most likely the quickest killer of castaways. A shipwrecked sailor without a raft, floating in water as warm as even 59 degrees Fahrenheit, will be unlikely to live more than a few hours. A thick layer of fat, the human equivalent of blubber, will provide protective insulation but will prolong life for only a limited amount of time. In one recent incident, a heavyset man who fell from a cruise ship off the Florida coast managed to tread water for eight hours before the Coast Guard found him. His large size and the Gulf Stream waters—in the mid- to low 70s—protected him, and he was in reasonably good shape after his ordeal. Typically, a survivor cast into freezing water may be able to survive between 30 and 90 minutes. But “without a life jacket, or in rough seas, a person usually dies even more rapidly because they drown as they lose consciousness,” explains Frances Ashcroft, professor of physiology at the University of Oxford. Water is a much better conductor of heat than air is, so it’s harder for the human body to tolerate cold water.

Shivering and trying to warm the body by exercising only contribute to heat loss; the cold water absorbs the heat far more quickly than the body can create it and cools the extremities, which then cool the body’s core. Once the blood temperature drops below 94°F, hypothermia starts to take its toll: Thinking and coordination become impaired and urination increases, which speeds up dehydration. Eventually, coma and heart failure ensue. The official cause of death for the crew of the Titanic was drowning, but hypothermia from the frigid waters of the North Atlantic is what killed them.

Warm water is crucial for survival. As Piantadosi says, “The closer to the equator you are when you are shipwrecked, the better.” He says that castaways who are adrift within 20 degrees north or south of the equator have the best chance of surviving. The warmer waters of the Gulf Stream also offer some protection. In one of the most harrowing stories of shipwreck and survival in recent memory, a young Deborah Kiley (she’s now 49) escaped dehydration, hypothermia, and sharks for five days on a small rubber dinghy in the Atlantic Ocean. She was one of a five-person crew hired to sail a boat from Maine to Florida in 1982 when it got caught in a violent storm off the Carolina coast. The boat went down so quickly, the crew was left without any supplies. Gale force winds and waves buffeted the life raft, and the only way the crew could keep hold of it was to flip it over and hang onto it from underneath, floating in the water. “We went down in the Gulf Stream,” Kiley says. “If we had sunk anywhere else in the Atlantic Ocean, we would have died in the first 30 to 35 minutes.”

The air temperature was a cold 42°F; the water was warmer, probably about 76°F, Kiley says. That’s another reason they opted to stay in it. Even then, “our teeth were chattering and our chests tightened. We were all having trouble breathing,” she recalls. To their horror they also discovered sharks swimming beneath them. That’s when they flipped the raft and got back in. In her book about the ordeal, The Sinking: One Woman’s True Story of Survival at Sea, Kiley recounts how, worried about hypothermia, she pulled seaweed from the ocean to warm their bodies at least a little.

The Mexican fishermen fared better because they were lucky: They drifted southwest from Mexico toward the equator and its warmer waters, not away from it. They were also resourceful, able to rig up a covering to protect them from the sun. Ironically, hot sunshine can contribute to hypothermia, which damages the skin’s capillaries, Piantadosi points out. “They don’t work as well after a burn, so the heat tends to leave faster,” he says. Cold temperature and sun exposure combine to create a dangerous situation.

A Terrible Thirst and Hunger

Experts estimate that a castaway drifting under the harsh tropical sun without any shade requires about five quarts of water each day to keep from becoming dehydrated, a formidable amount for someone in a life raft. Some life rafts come equipped with devices to convert seawater to freshwater, but the amount of drinkable water they make is limited. The temptation to drink seawater can be great, but the dangers of drinking seawater are even greater. Piantadosi explains that the kidneys are not able to process the amount of salt in seawater, and so it builds up to toxic levels. It causes diarrhea, further dehydrating the body, and can also lead to hallucinations. Two of the crew with Deborah Kiley drank salt water the third day out, and both suffered delusions, leaving the security of the raft to swim off—one announced he was going to get the car. Both were attacked by sharks.

Interestingly, though, Piantadosi explains, drinking a little seawater (a cupful only) can be a onetime aid to survival. He explains that during the process of dehydration, the blood plasma (the liquid part of blood) becomes depleted of water, forcing the heart to push the blood cells through the body without enough fluid. Not surprisingly, blood flow drops, and vital organs do not get the nutrients and oxygen they need. Drinking salt water can keep the plasma volume up and help maintain circulation, if only temporarily. “If you think you have a chance of being rescued in a day or two, you might safely keep your blood plasma level up by taking a few sips of salt water,” Piantadosi says, “but if it’s unlikely that anyone knows you’re missing yet, or where you are, you shouldn’t.” After a few days, he says, your body won’t be able to get rid of the salt, which will kill you more quickly than if you didn’t drink any liquid at all.

The first two weeks adrift, the fishermen had limited water. They caught a sea turtle and got some relief by drinking its blood. They also drank small amounts of their own urine, which they believed was safer than drinking seawater. In fact, according to Piantadosi, it is just as dangerous to drink urine as it is to drink seawater. The salt content of urine is high, and it also contains urea, the ammonia-scented end product of protein metabolism that must be excreted from the body. Fortunately for the fishermen, during the second week, it began to rain. It rained so much that the empty gas tank they had cleaned and kept open to catch rain was always full. Nothing was more critical to their survival, except perhaps their ability to maneuver the boat through storm waves to keep it from capsizing.

Food is less of an issue for castaways than is water, especially for anyone who’s carrying extra pounds. “Although healthy individuals of normal body weight can fast for about 70 days, highly obese individuals can fast up to a year, depending on the amount of fat in reserve,” says Piantadosi.

The fishermen survived on raw fish and occasional seabirds that would sometimes alight on their boat. They had enough to eat. By contrast, most shipwreck survivors not only lose excess fat but also begin to burn muscle mass if they stay adrift for any length of time.

Mind Over Matter

From the first hours Kiley found herself being tossed around in the high surf, she resolved that she would survive. And from day one, her two crewmates—who were ultimately eaten by sharks—were convinced they were going to die. Similarly, fisherman Salvador Ordóñez says that he was confident that he would live. He and his two cosurvivors read the Bible and talked about what they would do when they got back to their families. They marveled at the whales that breached alongside their boat, and they took pleasure in the beautiful sunsets. Kiley, too, speaks of an experience of beauty that helped her concentrate on the moment.

But action is also needed. “The mind,” Kiley says, “is your greatest survival tool. To survive you need to live moment to moment and focus on what you have to do next.”

Being emotionally tough may be what enabled Kiley to hang on for as long as she did, but she survived because a Russian ship spotted her raft on the fifth day. Had it been the seventh or eighth day out, she would most likely not have lived to tell her story. Determination couldn’t have kept her alive much longer. Adrift in the ocean, ironically, what she needed most to survive was water.

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