Survival At Sea 1/2: Weather, Food, Water, Medical

Throughout the course of our beloved series, our stalwart heroes find themselves in many perilous situations that aren’t always directly related to combat (stranded on a tiny island during a storm, adrift on the open ocean without a raft, shipwrecked at least twice, etc.). Luckily, they have the survival skills to carry them through these adventures that they may live to fight the French another day. How many of us could say the same? Here is a guide to survival at sea, which as you’ll see includes many of the techniques PO’B wrote about. Hopefully none of us will ever need to use these tips, but I’m sure Stephen never thought he’d need them back when he was a landlocked physician in Minorca, either…

Survival At Sea

Perhaps the most difficult survival situation to be in is sea survival. Short- or long-term survival depends upon rations and equipment available and your ingenuity. You must be resourceful to survive. Water covers about 75 percent of the earth’s surface, with about 70 percent being oceans and seas. You can assume that you will sometime cross vast expanses of water. There is always the chance that the plane or ship you are on will become crippled by such hazards as storms, collision, fire or war.


As a survivor on the open sea, you will face waves and wind. You may also face extreme heat or cold. To keep these environmental hazards from becoming serious problems, take precautionary measures as soon as possible. Use the available resources to protect yourself from the elements and from heat or extreme cold and humidity. Protecting yourself from the elements meets only one of your basic needs. You must also be able to obtain water and food. Satisfying these three basic needs will help prevent serious physical and psychological problems. However, you must know how to treat health problems that may result from your situation.

Precautionary Measures

Your survival at sea depends upon —

  • Your knowledge of and ability to use the available survival equipment.
  • Your special skills and ability to apply them to cope with the hazards you face.
  • Your will to live.

When you board a ship or aircraft, find out what survival equipment is on board, where it is stowed and what it contains. For instance, how many life preservers and lifeboats or rafts are on board? Where are they located? What type of survival equipment do they have? How much food, water and medicine do they contain? How many people are they designed to support? If you are responsible for other personnel on board, make sure you know where they are and they know where you are.

The Basics

There’s nothing romantic about being a castaway. Even Tom Hanks was reduced to wailing over the loss of a volleyball, his only companion.

Surviving at sea is a grueling challenge, one that grows more demanding and draining by the day. So whatever you can do to reduce your risks and hold on to your strength could make a huge difference in determining whether or not you ever see land again.

With luck, you’ll have the use of a life raft, which is more stable than a dinghy. If not, and you have to swim, grab anything that will help you float. Obviously, a life jacket is your best bet, but failing that, look for plastic containers used for food or fuel or buoys or even a piece of wood. The key is to find ways to save your energy. Swimming furiously is a sure way to exhaust yourself.

One of the first decisions you’ll need to make is whether to try to stay near where you abandoned ship or head to where you think may be land. If you were able to send out a distress signal or if you’re near shipping lanes, try to stay put. Only paddle for shore if you have some idea of where you’re going. Remember, you want to save your energy. Another dark reality: A lot of people drown near the beach because of rip currents or high surf. So don’t frantically head for what you think is land.

If you have a raft, try to take along as much warm and protective clothing as you can handle — wool and polypropylene and anything that’s windproof or waterproof. Once in the raft, protect yourself from the wind, using clothing or a tarp. And stay as dry as you can. Even in a raft the combination of wind and wet clothes could cause hypothermia.

Conversely, depending on your location, you also run the risk of getting dehydrated. Since fresh water is such a valuable commodity, you don’t want to sweat any more than necessary, so limit both your physical exertion and exposure to the sun. If you can, make a sun shade with sails or a tarp. And if the weather is hot, keep your clothes on and get them wet. That will keep you cool and also protect you from getting badly sunburned.

Remember that salt water drains your skin’s moisture, causing it to dry and crack in the hot sun. And constant rubbing with salt water can irritate your skin. The bottom line is that the combination of sun and salt water can do a lot of damage, so do what you can to keep your skin covered. If you’re not lucky enough to have sunscreen with you, try using grease if you can find some. Also, do what you can to protect your eyes. If you don’t have sunglasses, try tying a band of fabric over your eyes after cutting slits to allow you to see.

Some people insist that it’s possible to drink up to 32 ounces of seawater a day without doing irreparable harm to your body, particularly your kidneys. But don’t even consider that risk unless you have no access to fresh water. If you have a supply of water, start rationing right away. You really won’t need to drink much water the first day, no matter how thirsty you feel. Then try to limit your intake to 12 to 16 ounces for a few days, eventually dropping it as low as two to five ounces a day. You can survive, but you’ll definitely become weaker.

That’s why capturing rainwater can be critical to your survival. Take a tarp or sail and shape it into a bowl to catch the rain. Even a garbage bag could work. Make sure you have some sort of water container set up at all times; you’d hate to lose a chance to collect water during a storm in the middle of the night. Ideally, you’ll have a can or bottle you can store rainwater in. If not, look for anything that can hold water; you don’t want your precious supply washed away by rough seas. And if you haven’t been drinking much, don’t guzzle a fresh supply of rainwater. That will make you sick.

Of course, you’ll get hungry, but remember that you can live longer without food than without water. Fish is an obvious option, but keep in mind that fish is high in protein and digesting protein uses up more of your body’s water supply. The same is true of seaweed. Better to stick with carbs as long as you can — that’s why they’re so plentiful in survival rations.

So how can you tell if you’re getting close to land? Well, birds overhead is a good sign, especially at night when they tend to fly to shore. So is drifting wood. A few other things to keep in mind: Cumulus clouds usually form over land, and wind generally blows toward land during the day and out to sea at night.

Weather Conditions

If you are in a cold climate —

  • Put on an antiexposure suit. If unavailable, put on any extra clothing available. Keep clothes loose and comfortable.
  • Take care not to snag the raft with shoes or sharp objects. Keep the repair kit where you can readily reach it.
  • Rig a windbreak, spray shield and canopy.
  • Try to keep the floor of the raft dry. Cover it with canvas or cloth for insulation.
  • Huddle with others to keep warm, moving enough to keep the blood circulating. Spread an extra tarpaulin, sail or parachute over the group.
  • Give extra rations, if available, to survivors suffering from exposure to cold.

The greatest problem you face when submerged in cold water is death due to hypothermia. When you are immersed in cold water, hypothermia occurs rapidly due to the decreased insulating quality of wet clothing and the result of water displacing the layer of still air that normally surrounds the body. The rate of heat exchange in water is about 25 times greater than it is in air of the same temperature.

Your best protection against the effects of cold water is to get into the life raft, stay dry and insulate your body from the cold surface of the bottom of the raft. If these actions are not possible, wearing an antiexposure suit will extend your life expectancy considerably. Remember, keep your head and neck out of the water and well insulated from the cold water’s effects when the temperature is below 19 degrees C. Wearing life preservers increases the predicted survival time as body position in the water increases the chance of survival.

If you are in a hot climate —

  • Rig a sunshade or canopy. Leave enough space for ventilation.
  • Cover your skin, where possible, to protect it from sunburn. Use sunburn cream, if available, on all exposed skin. Your eyelids, the back of your ears and the skin under your chin sunburn easily

Drinking Water At Sea

Water is your most important need. With it alone, you can live for 10 days or longer, depending on your will to live. When drinking water, moisten your lips, tongue and throat before swallowing.

Short Water Rations

When you have a limited water supply and you can’t replace it by chemical or mechanical means, use the water efficiently. Protect freshwater supplies from seawater contamination. Keep your body well shaded, both from overhead sun and from reflection off the sea surface. Allow ventilation of air; dampen your clothes during the hottest part of the day. Do not exert yourself. Relax and sleep when possible. Fix your daily water ration after considering the amount of water you have, the output of solar stills and desalting kit, and the number and physical condition of your party.

If you don’t have water, don’t eat. If your water ration is 2 liters or more per day, eat any part of your ration or any additional food that you may catch, such as birds, fish and shrimp. The life raft’s motion and anxiety may cause nausea. If you eat when nauseated, you may lose your food immediately. If nauseated, rest and relax as much as you can and take only water.

To reduce your loss of water through perspiration, soak your clothes in the sea and wring them out before putting them on again. Don’t overdo this during hot days when no canopy or sun shield is available. This is a trade-off between cooling and saltwater boils and rashes that will result. Be careful not to get the bottom of the raft wet.

Watch the clouds and be ready for any chance of showers. Keep a tarpaulin handy for catching water. If it is encrusted with dried salt, wash it in seawater. Normally, a small amount of seawater mixed with rain will hardly be noticeable and will not cause any physical reaction. In rough seas you cannot get uncontaminated fresh water.

At night, secure the tarpaulin like a sunshade and turn up its edges to collect dew. It is also possible to collect dew along the sides of the raft using a sponge or cloth. When it rains, drink as much as you can hold.

Desalting Kits

When desalting kits are available in addition to solar stills, use them only for immediate water needs or during long overcast periods when you cannot use solar stills. In any event, keep desalting kits and emergency water stores for periods when you cannot use solar stills or catch rainwater.

Water From Fish

Drink the aqueous fluid found along the spine and in the eyes of large fish. Carefully cut the fish in half to get the fluid along the spine and suck the eye. If you are so short of water that you need to do this, then do not drink any of the other body fluids. These other fluids are rich in protein and fat, and will use up more of your reserve water in digestion than they supply.

Sea Ice

In arctic waters, use old sea ice for water. This ice is bluish, has rounded comers and splinters easily. It is nearly free of salt. New ice is gray, milky, hard and salty. Water from icebergs is fresh but icebergs are dangerous to approach. Use them as a source of water only in emergencies.


Do not drink seawater. Do not drink urine. Do not drink alcohol. Do not smoke. Do not eat, unless water is available.

Sleep and rest are the best ways of enduring periods of reduced water and food intake. However, make sure that you have enough shade when napping during the day. If the sea is rough, tie yourself to the raft, close any cover and ride out the storm as best you can. “Relax” is the keyword — at least try to relax.

Food Supply At Sea

In the open sea, fish will be the main food source. There are some poisonous and dangerous ocean fish but, in general, when out of sight of land, fish are safe to eat. Nearer the shore there are fish that are both dangerous and poisonous to eat. There are some fish, such as the red snapper and barracuda, that are normally edible but poisonous when taken from the waters of atolls and reefs. Flying fish will even jump into your raft!


When fishing, do not handle the fishing line with bare hands and never wrap it around your hands or tie it to a life raft. The salt that adheres to it can make it a sharp cutting edge, an edge dangerous both to the raft and your hands. Wear gloves, if they are available, or use a cloth to handle fish and to avoid injury from sharp fins and gill covers.

In warm regions, gut and bleed fish immediately after catching them. Cut fish that you do not eat immediately into thin, narrow strips and hang them to dry. A well-dried fish stays edible for several days. Fish not cleaned and dried may spoil in half a day. Fish with dark meat are very prone to decomposition. If you do not eat them all immediately, do not eat any of the leftovers. Use the leftovers for bait.

Never eat fish that have pale, shiny gills; sunken eyes; flabby skin and flesh; or an unpleasant odor. Good fish show the opposite characteristics. Sea fish have a saltwater or clean fishy odor. Do not confuse eels with sea snakes that have an obviously scaly body and strongly compressed, paddle-shaped tail. Both eels and sea snakes are edible, but you must handle the latter with care because of their poisonous bites. The heart, blood, intestinal wall and liver of most fish are edible. Cook the intestines. Also edible are the partly digested smaller fish that you may find in the stomachs of large fish. In addition, sea turtles are edible.

Shark meat is a good source of food whether raw, dried or cooked. Shark meat spoils very rapidly due to the high concentration of urea in the blood; therefore, bleed it immediately and soak it in several changes of water. People prefer some shark species over others. Consider them all edible, except the Greenland shark whose flesh contains high quantities of vitamin A. Do not eat the livers, due to high vitamin A content.

Fishing Aids

  • You can use different materials to make fishing aids as described in the following paragraphs:
  • Fishing line. Use pieces of tarpaulin or canvas. Unravel the threads and tie them together in short lengths in groups of three or more threads. Shoelaces and parachute suspension line also work well.
  • Fish hooks. No survivor at sea should be without fishing equipment but if you are, improvise hooks.
  • Fish lures. You can fashion lures by attaching a double hook to any shiny piece of metal.
  • Grapple. Use grapples to hook seaweed. You may shake crabs, shrimp or small fish out of the seaweed. These you may eat or use for bait. You may eat seaweed itself but only when you have plenty of drinking water. Improvise grapples from wood. Use a heavy piece of wood as the main shaft and lash three smaller pieces to the shaft as grapples.
  • Bait. You can use small fish as bait for larger ones. Scoop the small fish up with a net. If you don’t have a net, make one from cloth of some type. Hold the net under the water and scoop upward. Use all the guts from birds and fish for bait. When using bait, try to keep it moving in the water to give it the appearance of being alive.

Helpful Fishing Hints

Your fishing should be successful if you remember the following important hints:

  • Be extremely careful with fish that have teeth and spines.
  • Cut a large fish loose, rather than risk capsizing the raft. Try to catch small, rather than large, fish.
  • Do not puncture your raft with hooks or other sharp instruments.
  • Do not fish when large sharks are in the area.
  • Watch for schools of fish; try to move close to these schools.
  • Fish at night using a light. The light attracts fish.
  • In the daytime, shade attracts some fish. You may find them under your raft.
  • Improvise a spear by tying a knife to an oar blade. This spear can help you catch larger fish but you must get them into the raft quickly or they will slip off the blade. Also, tie the knife very securely or you may lose it.
  • Always take care of your fishing equipment. Dry your fishing lines, clean and sharpen the hooks, and do not allow the hooks to stick into the fishing lines.


All birds are edible. Eat any birds you can catch. Sometimes birds may land on your raft, but usually they are cautious. You may be able to attract some birds by towing a bright piece of metal behind the raft. This will bring the bird within shooting range, provided you have a firearm.

If a bird lands within your reach, you may be able to catch it. If the birds do not land close enough or land on the other end of the raft, you may be able to catch them with a bird noose. Bait the center of the noose and wait for the bird to land. When the bird’s feet are in the center of the noose, pull it tight.

Use all parts of the bird. Use the feathers for insulation, the entrails and feet for bait, and so on. Use your imagination.

Medical Survival At Sea

At sea, you may become seasick, get saltwater sores, or face some of the same medical problems that occur on land, such as dehydration or sunburn. These problems can become critical if left untreated.


Seasickness is the nausea and vomiting caused by the motion of the raft. It can result in —

  • * Extreme fluid loss and exhaustion.
  • * Loss of the will to survive.
  • * Others becoming seasick.
  • * Attraction of sharks to the raft.
  • * Unclean conditions.

To treat seasickness —

  • Wash both the patient and the raft to remove the sight and odor of vomit.
  • Keep the patient from eating food until his nausea is gone.
  • Have the patient lie down and rest.
  • Give the patient seasickness pills if available. If the patient is unable to take the pills orally, insert them rectally for absorption by the body.

Note: Some survivors have said that erecting a canopy or using the horizon as a focal point helped overcome seasickness. Others have said that swimming alongside the raft for short periods helped, but extreme care must be taken if swimming.

Saltwater Sores

These sores result from a break in skin exposed to salt water for an extended period. The sores may form scabs and pus. Do not open or drain. Flush the sores with fresh water, if available, and allow to dry. Apply an antiseptic, if available.

Immersion Rot, Frostbite and Hypothermia

These problems are similar to those encountered in cold weather environments. Symptoms and treatment are the same.


If flame, smoke or other contaminants get in the eyes, flush them immediately with salt water, then with fresh water, if available. Apply ointment, if available. Bandage both eyes 18 to 24 hours or longer if damage is severe. If the glare from the sky and water causes your eyes to become bloodshot and inflamed, bandage them lightly. Try to prevent this problem by wearing sunglasses. Improvise sunglasses if necessary.


This condition is a common problem on a raft. Do not take a laxative, as this will cause further dehydration. Exercise as much as possible and drink an adequate amount of water, if available.

Difficult Urination

This problem is not unusual and is due mainly to dehydration. It is best not to treat it, as it could cause further dehydration.


Sunburn is a serious problem in sea survival. Try to prevent sunburn by staying in shade and keeping your head and skin covered. Use cream or lip balm from your first aid kit if available. Remember, reflection from the water also causes sunburn.

Courtesy of The Discovery Channel.
Image: The Shipwreck by JMW Turner.

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