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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.

Staying Hydrated

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.

Finding Food

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.

Information courtesy of the U.S. Army Survival Manual