SURVIVAL AT SEA

The sea is pitiless when it comes to survival situations: your first mistake in a maritime emergency is likely to be your last. You must master every ocean survival technique in order to live in this unforgiving environment.

Around 71 per cent of the earth’s surface is covered by water. It is therefore imperative that you learn how to survive in this environment. Man’s natural domain is land, and that makes survival at sea for any length of time a formidable challenge. In particular, acquiring drinking water and food are serious problems for the survivor at sea, though the other dangers that the sea poses to the survivor should not be underestimated.

CHARACTERISTICS OF THE TERRAIN

Around the poles, the limit of the solidly frozen arctic ice pack varies in latitude from 65 to 75 degrees between February and August. In winter, in each hemisphere, there are cyclonic storms characterised by snow, winds of up to 64km/hr (40mph), temperatures as low as -50 degrees C (-122 degrees F), and gale-force winds. In summer, there are periods of calm or days with light winds. Skies are overcast, there are dense fog banks during calm periods, and rain or drizzle may last for weeks.

Around the 40 degrees latitudes in each hemisphere there is generally fair, clear weather, with temperatures of around 10 degrees C (50 degrees F) in the winter and around 21 degrees C (70 degrees F) in summer. Below a 25-degree latitude, in the heart of the trade wind belt, winds of 8-24km/hr (5-15mph) are normal. There is little difference between summer and winter, with temperatures being in the 21-27 degrees C (70-80 degrees F) range.

Between five degrees north and five degrees south in the Atlantic, Pacific and Indian Oceans, there is an equatorial trough of low pressure where there are no prevailing surface winds. As a result, there are shifting winds and calms. Solar heat results in violent thunderstorms.

Waterspouts (the marine equivalent of tornados) are common off the Atlantic and Gulf coasts of the USA and along the coasts of China and Japan. Hurricanes and typhoons occur in the warm areas of all oceans during the summer and autumn. They can last for up to two weeks.

Salinity The average salinity of the seas is around 3.5 per cent, though higher values occur at or near the surface in areas where high temperatures and strong, dry winds favour evaporation. The highest salinities occur in semi-landlocked seas at mid-latitudes, such as the Red Sea, the Persian Gulf and the Mediterranean Sea. The salt in the water makes it undrinkable and can aggravate open sores and cuts (see below).

IMMEDIATE ACTIONS

When you hit the water, try to make your way to a raft. If none is available, try to find a large piece of floating debris to cling to. Try to stay calm: a relaxed body will stay afloat. Floating on your back requires less energy than swimming face-down. Alternatively, float face-down on the surface with your arms outstretched and legs pointing towards the bottom. To breathe, raise your head and place your arms in the outstretched position again.

Cold water If the water is cold, you risk dying of hypothermia if fully immersed. You must get into a raft and insulate your body from the cold bottom of the raft. If there isn’t a raft, keep still and assume the Heat Escape Lessening Posture (HELP) position: this will increase your survival time. Around 50 per cent of the body’s heat is lost from the head, therefore try to keep your head out of the water.

If there are several of you in the water, huddle close in a circle to preserve body heat. However, note that these measures are only temporary – YOU MUST GET OUT OF THE WATER.

Clothing at sea If you are adrift in a cold ocean, you must try to stay dry and keep warm (use a wind screen to decrease the cooling effects of the wind). If possible, remove, wring out and replace outer garments or change into dry clothing. If any survivors have dry clothes, they should share them with those who are wet. Those who are wet should be given the most sheltered positions in the raft, and let them warm their hands and feet against those who are dry. If possible, give extra water rations to those suffering from cold exposure.

Survivors use any extra clothing they have (drape it around the shoulders), and cover the floor of the raft with any spare material to help keep it insulated. Huddle together on the floor of the raft and spread extra sail or parachute material over the group.

You should exercise fingers, toes, legs, arms, shoulders and buttocks to prevent muscle spasms, help keep the body warm and prevent medical problems, such as constipation. Put your hands under your armpits then raise your feet slightly off the ground and keep them up for a minute or two. Try to exercise at least twice a day.

BRITISH SAS TIPS:

WHEN ABANDONING SHIP

Abandoning ship is a frightening experience, but you must act quickly. Follow these SAS guidelines and save your life.

• Put on warm, preferably woollen, clothing, including hat and gloves. Wrap a towel around your neck.
• Take a torch or flashlight.
• Grab chocolates and sweets if possible.
• Do not inflate your life jacket until you leave the ship.
• When jumping overboard, first throw something (anything wooden) that floats and jump close to it.
• Air trapped in clothing will help buoyancy: do not take off your clothes in the water.

US ARMY TIPS:

RECOMMENDED SWIMMING STROKES FOR SURVIVORS

You must try to conserve your strength when you are in the water. Use a variety of these swimming strokes when you have survived a disaster:

• Dog paddle: good for when you are clothed or wearing a life jacket.
• Breast stroke: good for swimming underwater or in rough seas.
• Side stroke: a useful relief stroke because only one arm is needed to maintain momentum and buoyancy.
• Back stroke: another good relief stroke. It relieves the muscles that are used for other strokes.

Picking up survivors If you are in a life raft and are rescuing people in the water, try to throw them a line with a life belt attached. Alternatively, send a swimmer out with a line attached to a flotation device. If you are in the water rescuing people, approach them from behind to avoid getting kicked, grabbed or scratched. Grab them by the back of their life jacket or hold them under the chin and then use a sidestroke to drag them to the raft. Try to reassure them as you do so. DO NOT UNDERESTIMATE THE STRENGTH OF A PERSON IN A STATE OF PANIC IN THE WATER.

CANADIAN AIR FORCE TIPS:

LIFE RAFT ROUTINE

When adrift in a life raft you must undertake the following practices to keep the raft seaworthy and maintain morale.

• Repair the raft as soon as it gets damaged with patches or other materials (check the raft frequently for any damage).
• Bleed off air if the raft expands in hot weather.
• Top up air if the raft contracts in cold weather or at night.
• Relax and try to keep your mind occupied: keep a log.
• If in a group, form a team and ensure everyone has a job to do. This will help to pass the time and lessen the possibility of seasickness.

MOVEMENT

You must remember one thing when afloat in the ocean: your raft will be at the mercy of winds and currents. Currents flow in a clockwise direction in the Northern Hemisphere and anti-clockwise in the Southern Hemisphere. Sea currents travel at speeds of less than 8km/hr (5mph), so movement is going to be very slow. In areas where warm and cold currents meet there will often be storms, dense fog, high winds and heavy seas. These will make movement difficult and dangerous.

BRITISH SAS TIPS:

RIGHTING AN INFLATABLE DINGHY

A capsized dinghy need not be a catastrophe in a survival situation at sea: you can right it easily if you know how.

• Grab the righting line from the opposite side.
• Brace your feet against the dinghy and pull.
• The dinghy should rise up and over, and will pull you temporarily out of the water.
• This procedure requires more effort in heavy seas or high winds.

Winds and waves can aid raft travel. Winds blow in an easterly direction in tropical areas, the so-called trade winds, and from the west in higher latitudes. To take advantage of the wind you will need a sail. If the raft doesn’t have one, improvise one from a poncho or other piece of material.

Waves can be both an asset and a hazard. The size of waves is usually dependent upon the severity of the wind. Waves will only move a raft a few centimetres at a time under normal conditions, so they are of little use as a means of propulsion. However, they are an asset when you are searching for shallow areas or land. Ocean waves break when they enter shallow water or when they encounter an obstruction. Use breaking waves as an aid to making a landfall. Waves can also capsize a raft in bad weather, or fill it with water.

BRITISH SAS TIPS:

INDICATORS THAT LAND IS NEARBY

As a survivor at sea, your number one priority is to reach land. Keep a lookout for the following objects and signs that can point to land.

• Clouds. Cumulus clouds (fluffy, white ones) in a clear sky are likely to have been formed over land. In tropical areas, a green tint on the underside of clouds is caused by the reflection of sunlight from the shallow water over coral reefs.
• Birds usually fly from land before midday and return to it in the late afternoon. Beware of lone birds though: they may just be disorientated.
• Coconuts, driftwood and drifting vegetation can sometimes indicate that land is near.
• A change in the direction of sea movement may be caused by the tide around an island.
• Water that is muddy with silt has probably come from the mouth of a large river that is nearby.
• Deep water is dark-green or dark-blue: a lighter colour indicates shallow water and perhaps land.

To move or stay put? If an SOS has been sent (see Signalling and Navigation Chapter), or you know you are in regular shipping lanes, you should stay in the same location for up to 72 hours. However, if you are off the shipping lanes and didn’t manage to send a signal, then you should get underway as soon as possible to take advantage of your fitness and stamina. Head in the direction of land. If there is no land nearby, try to work out where the nearest shipping lane is and head in that direction.

Signalling Use flares and dye markers (which spread brightly coloured dye in the sea) if you have them to attract the attention of a ship or aircraft. If you do not have any signalling equipment, attract attention to yourself by waving clothing and other materials, brightly coloured if possible. Sea markers should only be used in daylight (they normally last for around three hours). A mirror or reflective surface can be used for long-range signalling.

All flares should be handled carefully. Keep them dry and secure, and when firing point them upwards and away from yourself and anyone else in the raft. Use them only when you are sure that they will be seen. A shiny, reflective surface is also an excellent way of attracting attention to yourself.

If you have a radio transmitter in your life raft, it will have preset frequencies at 121.5 and 243 megacycles, and will have a range of around 32km (20 miles). Try to transmit at frequent intervals but be careful not to run down the batteries (if you have a watch you can use it to time signals at regular intervals – remember to keep all watches dry).

Getting ashore Once you have sighted land you will obviously make for it without delay.

If you are swimming, wear your shoes and at least one thickness of clothing. Use side or breast stroke to conserve your strength. Water is calmer in the lee of a heavy growth of seaweed. DO NOT swim through it: crawl over the top by grasping the vegetation

If you are in a raft, choose your landing point carefully. Do not land when the sun is low and straight in front of you, and avoid coral reefs and rocky cliffs. Similarly, stay well clear of rip currents (a strong surface current) or strong tidal currents. Use oars and paddles if you have them and adjust the sea anchor to keep a strain on the anchor line. This will prevent the sea from throwing the stern around and will keep the raft pointed towards the shore.

In heavy surf try to avoid meeting a large wave at the precise moment it breaks. As you near the beach, try to tide the raft on the crest of a wave. Do not jump out until the raft has grounded, and then get out quickly and pull it ashore. If you come across sea ice, try to land on large, stable floes. Use the oars to keep the raft’s edge away from ice edges, and remember that when you are on a floe it may break up at any time. Keep the raft ready.

SEAL TIPS:

SWIMMING ASHORE

In the water and approaching a shore line? Though you are in sight of land you are also in potential danger. Employ SEAL tactics to land safely.

• Ride in on the back of a small wave by swimming forward with it.
• In high waves, swim towards the shore in the trough between waves. Face and submerge beneath waves, then swim forward in the next trough.
• If caught in the undertow of a large wave, let it pass over and then push off the bottom with your feet or swim to the surface if in deep water.
• When landing on a rocky shore, aim for the place where the waves rush up onto the rocks, not where they explode with a high white spray.
• To land, advance behind a large wave into the breakers. Face the shore with your feet in front, 0.5-1m (2-3ft) lower than your head. In this way your feet will absorb shocks when you land or hit submerged rocks or reefs, and you will not get injured.
• If you don’t reach shore behind the wave you have selected, swim using your hands only. Adopt a sitting position as the next wave approaches and carries you to shore.

DANGERS

The many dangers at sea, such as hostile fish, the threat of starvation and thirst and the cold and wet, can all be dealt with to varying degrees, though remember that you rarely get a second chance at sea. Stay alert!

Sharks are scavengers and live in almost all seas and oceans. They feed more actively at night, and especially at dawn and dusk, and after dark they move towards the surface and into shallow waters. They are attracted to rubbish, body wastes and blood, and also by weak fluttery movements similar to a wounded fish. A shark cannot stop suddenly or turn quickly in a tight circle, and it will rarely jump out of the water to take food. For this reason, people on rafts are relatively safe from attack, unless they dangle their legs or arms in the water.

If you are on a raft or dinghy, do not fish when sharks are around and do not throw any waste overboard. If it looks as though a shark is going to attack, try to jab its snout with a pole or pebble.

If you catch a small shark while fishing, try to haul it in to the side, pull its head clear and then club it hard before hauling it aboard. You must ensure it is stunned before approaching it and finishing it off. If you catch a large shark, cut the line and let it go: it could damage your vessel and injure you. In addition, its threshing will attract other sharks.

The main types of shark that have been known to attack humans are listed below, but be aware that all sharks, because of their sharp teeth and aggressive feeding habits, must be considered potentially dangerous. One more thing: there is no relationship between the size of a shark and the risk of attack.

NURSE Appearance: greyish coloured on top, white underneath, very heavily built and large-finned.

Size: around 4m (13ft).

Temperament and habits: aggressive, often found close inshore.

Distribution: around eastern Australia.

BULL SHARK Appearance: grey on top, white underneath with a stout body.

Size: up to 4m (12ft).

Temperament and habits: likes shallow waters and rivers. Aggressive.

Distribution: tropical west Atlantic with close relatives off southern Africa and in the Indian Ocean.

HAMMERHEAD SHARK Appearance: flat, hammer-like head, long body.

Size: up to 6m (18ft).

Temperament: can be aggressive.

Distribution: tropical and subtropical waters.

TIGER SHARK Appearance: grey on top, white underneath with a very wide head and jaws.

Size: 3-3.5m (12-13.5ft).

Temperament and habits: often found close inshore, can be dangerous.

Distribution: tropical and subtropical waters.

MAKO SHARK Appearance: ultramarine blue on top and creamy-white underneath. Brightly coloured.

Size: 2-3m (6-9ft).

Temperament and habits: can swim very quickly, sometimes leaps from the water when agitated.

Distribution: warm temperate waters.

SEAL TIPS:

ANTI-SHARK MEASURES IF YOU ARE IN THE WATER

SEAL team members are often on operations in shark-infested waters. They have tried and tested anti-shark measures.

• If you are in a group in the water, bunch together and form a tight circle for added protection.
• Face outwards and keep a lookout for sharks.
• Ward off an attack by kicking or stiff-arming a shark. Only use your hands as a last resort. Use a hard object, such as a knife, and aim for the snout, gills or eyes.
• Urinate in short, sharp bursts and allow it to dissipate between spurts. Collect faeces and throw as far away from you as possible. Try to re-swallow vomit or, failing that, throw it as far away as possible.
• Stay as quiet as possible and float to save energy.
• If you have to swim, use strong regular strokes, not frantic irregular movements (these will make sharks believe you are a wounded fish).
• Do not swim directly away from a shark; rather, face it and swim to one side, using strong, rhythmic movements.

GREAT WHITE SHARK Appearance: grey on top, white underneath, thick body, conical snout and black eyes.

Size: up to 6m (18ft).

Temperament: very aggressive.

Distribution: found in all the warm and temperate oceans of the world, but especially off southern Africa, east and west of North America and southern Australia and New Zealand.

COW SHARK Appearance: sandy-grey with dark spots.

Size: up to 3m (9ft).

Temperament and habits: swims close to the surface, aggressive.

Distribution: tropical and subtropical waters.

SAND SHARK Appearance: white underneath, mouse-grey on top with yellow spots, hence its name.

Size: up to 3m (9ft).

Temperament and habits: aggressive when provoked.

Distribution: tropical and subtropical waters.

SNAGGLETOOTH Appearance: coloured golden brown or grey.

Size: 2.5m (6ft).

Temperament and habits: can be found in shallow waters, can be aggressive.

Distribution: tropical waters.

SILVERTIP SHARK Appearance: charcoal, white tips on fins.

Size: 3m (9ft).

Temperament and habits: fast and bold, potentially dangerous. Plentiful around reefs and islands.

Distribution: tropical and subtropical waters

GREY REEF SHARK Appearance: grey, tail edged with black.

Size: 2.5m (6ft).

Temperament and habits: curious but not aggressive.

Distribution: tropical waters.

COPPER SHARK Appearance: golden brown and cream underneath.

Size: 3m (10ft).

Temperament and habits: can be very aggressive.

Distribution: tropical and subtropical waters.

BULL SHARK Appearance: grey on top, off-white underneath.

Size: 3.5m (11.5ft).

Temperament and habits: dangerous: the most feared of tropical sharks.

Distribution: the tropics: will swim up rivers.

BLUE SHARK Appearance: brilliant blue on top, white underneath.

Size: 4m (13ft).

Temperament and habits: one of the most dangerous sharks in the ocean; responsible for many human fatalities and injuries.

Distribution: worldwide in tropical and temperate waters.

Remember that not all fish you see with fins are sharks. For example, dolphins and porpoises have long snouts and are enemies of sharks, while being no threat to humans. Giant rays are present in tropical waters. Sometimes they curl up the tips of their fins, and this may look like two sharks swimming side by side. All rays are harmless to survivors in deep water, but in shallow waters some are dangerous if stepped on: they have venomous spikes in the tail.

BRITISH SAS TIPS:

AGGRESSIVE FISH

Take note of the following fish: they may be dangerous in a survival situation. Above all, learn to recognise them and give them a wide berth.

• The Sea Bass is curious and bold. It is found around rocks, caverns, old wrecks and caves. Avoid these areas.
• Moray eels live in holes and crevices. They are aggressive if disturbed. If you are attacked, try to cut off its head since they retain their grip until dead (this may be difficult because they are slippery to the touch).
• Sea snakes are deadly poisonous. They are unlikely to bite but stay well clear of them.

Killer whales usually hunt in packs of up to 40 and sometimes attack anything that floats or swims. Get out of the water if killer whales are nearby if you can. On ice, do not stand near seals, as the whale may mistake you for one and try to eat you. However, it must be stressed that the chances of being eaten by a killer whale are very low.

Barracuda Found in tropical and subtropical seas, this fish is attracted by anything that enters the water, and especially bright objects. Barracuda are very fast and often roam in shoals. They are dangerous when there is blood in the water. Try to wear dark-coloured clothing if you have to enter the water, and never wear anything shiny.

US AIR FORCE TIPS:

DEALING WITH JELLYFISH STINGS

A jellyfish sting can be extremely painful, and in extreme cases can be fatal. Follow these procedures for dealing with them.

• Remove tentacles or other matter from the skin immediately.
• Use clothing, seaweed or other material to do this.
• DO NOT rub the wound with anything, especially sand, as this may result in activating the stinging cells.
• DO NOT suck the wound.
• Try to alleviate the poison effects: try soap, lemon juice, plant juices, baking powder or urine, which has an ammonia content.
• Artificial respiration and CPR may be required (see First Aid Chapter).
• Since stings may result in convulsions, it is important to get the victim out of the water.

Jellyfish There are many different kinds of jellyfish. The largest can be of 1.8m (6ft) in diameter, with tentacles hanging down to a depth of up to 30m (100ft). These tentacles contain stinging cells that can inflict serious injury on the survivor. One of the deadliest is the sea wasp, which can cause death in as little as 30 seconds, though around three hours is normal.

All jellyfish should be given a wide berth, especially since their tentacles may trail a long way from the body. Following a storm in tropical areas where large numbers of jellyfish are present, you may be stung by pieces of floating tentacles that have been removed from the fish during the storm. Jellyfish washed up on a shore may look dead, but many can still inflict painful injuries. In general, try to get out of the water when jellyfish are present.

Poisonous fish There are many reef fish that are dangerous to eat, especially bottom dwellers and feeders. For example, many fish from reefs and lagoons are poisonous to eat. If in doubt do not eat. Fish toxins are water soluble and tasteless, therefore you cannot use the taste test (see Food Chapter) to prove edibility, and no amount of cooking will neutralise them. In addition, birds can be immune to these poisons: so just because you see a bird eating a fish, do not think that it is safe for you to eat it.

Ingestion of fish toxins can result in death in the worst cases. As soon as any symptoms arise – numbness, itching, reversal of temperature sensations, nausea – induce vomiting by administering saltwater or the whites of eggs (give victim a laxative if available). You may have to perform a cricothyrotomy (see First Aid Chapter) if the victim foams at the mouth and shows signs of respiratory distress. Cool showers may relieve itching. Be prepared to treat any other symptoms as and when they arise.

There are other fish that are dangerous to touch, either because they have venomous spines, e.g. stonefish, or because they have poisonous barbs in their tails, e.g. rays. The spines inject a venom that is excruciatingly painful. Keep shoes on at all times when you are walking through saltwater, and use a stick, not your hands, to explore sand, rocks and holes.

The survivor should be aware of the following poisonous fish:

RABBITFISH Appearance: bright yellow with tiny blue spots.

Size: around 25-30cm (10-12in).

Threats: has venomous spines along its fins.

Distribution: reefs in the Pacific and Indian Oceans.

SURGEONFISH Appearance: very brightly coloured (usually black, blue and yellow), small-mouthed.

Size: 20-25cm (8-10in).

Threats: spines on the sides of the tail can inflict severe wounds.

Distribution: all tropical waters.

SCORPIONFISH Appearance: reddish, striped, with long, wavy spin spines.

Size: 30-75cm (12-30in).

Threats: its sting is intensely painful.

Distribution: reefs in the tropical Indian and Pacific Oceans.

VENOMOUS TOADFISH Appearance: dull-green coloured and large-mouthed.

Size: 30-40cm (7-10in).

Threats: lie buried in the sand and have sharp, poisonous spines on their back.

Distribution: tropical waters off the coasts of Central and South America.

STONEFISH Appearance: drab coloured and lumpy shaped.

Size: around 40cm (16in).

Threats: dorsal spines inject a venom that is very painful, sometimes fatal.

Distribution: tropical Pacific and Indian Oceans.

SEAL TIPS:

TREATMENT OF POISONS INJECTED VIA FISH SPINES

Follow this effective SEAL treatment for dealing with poisons injected via the spines of tropical and subtropical fish.

• Irrigate wound with water.
• Make a small cut across the wound and apply suction. Even if no cut is made, suction should be applied to remove as much venom as possible.
• Suck out as much poison as possible.
• Soak the injured part in hot water for 30 minutes-one hour. The water should be as hot as is bearable. If the wound is on the face or body, use hot compresses.
• Clean the wound after soaking.
• Cover the wound area with antiseptic and a clean, sterile dressing.
• You may have to treat for shock (see First Aid Chapter).

Marine snails and slugs As a survivor you may come into contact with these gastropods when you are crossing coral reefs and sandy shores. Avoid them: the animal is capable of injecting its poison via a barb into the flesh of a victim. The sting made by a cone shell is a puncture-type wound.

When you are stung, the area around the wound will turn blue, swell, become numb, sting and burn. The degree of pain varies from person to person, though in all victims the numbness and tingling sensation around the wound quickly spread through the whole body. This can be followed in a matter of hours by complete muscular paralysis, coma and death.

There is no specific treatment for this kind of injury. The best that you can do is apply hot towels or soak the wound in hot water to relieve the pain. You may have to administer artificial respiration.

Octopus These creatures like to hide in holes or underwater caves. You should avoid these areas. The sharp parrot-like beak of the octopus makes two small puncture wounds when it bites you, and into these wounds it injects a toxic venom. You will feel immediate pain in the form of burning, itching or stinging. Bleeding will be profuse and the area around the wound may swell, turn red and feel hot. Especially dangerous is the blue-ringed octopus, found off eastern Australia, whose bite is lethal.

There in no known cure for the bite of the blue-ringed octopus. For other octopus bites, treat as for shock (see First Aid Chapter). Stop the bleeding and clean the wound area, since there may be more venomous saliva around the wound. Then treat symptoms as they arise.

Medical problems In a raft, do not expose yourself to the sun and wind needlessly. Keep a layer of clothing on at all times, especially on your head. If you are very hot, dip your clothing in the sea, wring it out and put it back on (this is an extreme measure). Place any injured persons on the floor of the raft and make them comfortable. Try to keep them as warm or cool, depending on the climate you are in, and as dry as possible.

Wear sunglasses or eye shields to protect your eyes from the sun’s glare. Be especially careful about reflection off the water, which intensifies the sun’s rays. Do not rub sore eyes: apply an antiseptic cream to the eye lids and bandage lightly instead.

For parched lips and cracked skin: apply sun cream or Vaseline and do not lick your lips. Cover dry skin to prevent further drying. Prolonged exposure to saltwater may produce cold sores. Try to keep your clothing as dry as possible. Clean the sores and apply antiseptic cream. Large sores should be covered with a dressing (change dressings regularly).

US ARMY TIPS:

TREATING SEASICKNESS

Seasickness is not a joke: it can seriously weaken sufferers and lower the morale of other survivors. Deal with it the US Army way.

• Wash patient and raft to remove the sight and smell of vomit.
• Do not let patient have food until his or her nausea has gone.
• Make patient lie down and rest.
• If available, administer seasickness pills.

FINDING WATER AND FOOD

Water The lack of drinking water is a major problem for the survivor at sea. Whatever water you have must be rationed at once. Never relax the ration: you do not know how long you will need it. NEVER DRINK SEA WATER OR URINE.

Water sources If your raft has a de-salter kit or a solar still, use according to the instructions provided. You should employ every means available to catch and store rain water. Use the canopy on the raft to collect rain (wash it in sea water prior to collecting rain, the slight salt content will cause you no ill effects). In addition, rig the canvas at night to catch any dew (see Water Chapter).

BRITISH SAS TIPS:

WATER RATIONS

At sea, water is your most precious commodity. Follow these water ration rules strictly to increase your chances of survival.

• Day 1. Give no water: the body can make use of its own water reserves. Be strict with this rule.
• Days 2-4. Give 400cc (14oz) if available.
• Day 5 onwards. Give 55-225cc (2-8oz) daily, depending on water availability and climate.

CANADIAN AIR FORCE TIPS:

REDUCING FLUID LOSS

Follow strictly these Canadian Air Force guidelines for reducing your body’s overall use and loss of fluids.

• If you do not have any water do not eat.
• In hot climates reduce loss of body fluids through perspiration by remaining inactive.
• Brush dried salt off the body with a dry cloth.
• Try to sleep and rest as much as possible to minimise fluid loss.
• Try not to get seasick. Vomiting means losing valuable fluids. Relax and focus your mind on other tasks.
• Do not drink alcohol: it dehydrates the body.
• Do not smoke: it increases thirst.
• Suck on a button to stimulate saliva and thus reduce the desire to drink.

When it is raining, drink as much rain water as possible while you are collecting it. However, remember to drink slowly. If you have been on a water ration, gulping down a lot of fluids will make you vomit.

Sea ice can be a source of drinking water, but only use old sea ice (it is blue-grey in colour and has rounded contours): it has very little salinity. Pools on old sea ice in summer can be drunk, though ensure the water is not from wave splashes (they wil be salty and undrinkable).

You can drink the aqueous fluid found along the spines and in the eyes of large fish. To get at the fluid along the spine cut the fish in half. Suck the eye. Do not drink any other of the fish’s body fluids: they are rich in protein and will use your body’s water supply to digest them.

Food The amount of food you should eat in a survival situation is in direct proportion to the amount of drinking water you have. Do not eat food if you have no water: it will only deplete your body fluids. If you have emergency rations only use them when they are really needed. Try to live off caught food if you can. Remember, you do not know how long you will be adrift.

Fish will be your main food source (flying fish may even jump into your raft!). In the open sea, out of sight of land, fish are generally safe to eat. However, do not eat fish that are brightly coloured, covered with bristles or spines, or those which puff up or have parrot-like mouths or humanoid teeth. Similarly, avoid fish eggs in clusters or clumps: these will be poisonous.

BRITISH SBS TIPS:

FISHING AT SEA

The men of the Special Boat Squadron are renowned aquatic soldiers. Follow their advice when fishing at sea.

• Do not touch the fishing line with bare hands when reeling in, and never wrap it around your hands or tie it to an inflatable dinghy. The salt on it makes a sharp cutting edge that is a danger to your hands and the raft.
• If you have gloves wear them when handling fish: that way, you will not get fins or fish teeth in your skin.
• Pass a net under your raft from one end to the other – fish and turtles are attracted to the shade under your raft (this requires at least two people to perform).
• Use a torch (flashlight) to attract fish at night.
• Use improvised hooks – small folding knives, wire, pieces of jagged metal – and small bright objects, such as buckles, for bait.
• Use offal from caught fish for bait.

Birds All sea birds are potential food. They will be attracted to your raft as a perching place. Wait till they settle, you may be able to grab them if they are exhausted by flying in bad weather. In addition, you can trap birds by trailing lines in the water with hooks baited with fish.

Seaweed You can collect seaweed around shore lines and in mid-ocean. Seaweed is a rich source of minerals, though it can act as a violent laxative if your stomach is not accustomed to it. Remember that seaweed absorbs fluids when your body is digesting it, so it should not be eaten when water is scarce. Because of its laxative effect, you should only eat small amounts of seaweed at a time. The main types of seaweed available to the survivor in the open seas are listed below:

ROCKWEED: a coarse, dark-green seaweed with large air bladders. It has no food value in itself, but in it and under it you may find small crabs and fish.

KELP: has a short cylindrical stem and thin, wavy olive-green or brown fronds. Found in the Atlantic and Pacific Oceans, usually on submerged ledges and rocky bottoms. You should boil it before eating.

IRISH MOSS: has a tough, elastic and leathery texture, though it becomes crisp and shrunken when dried. Boil before eating.

DULSE: has a short stem which broadens into a thin, broad, fan-shaped expanse that is dark red and has several round-tipped lobes. It is usually attached to rocks or coarser seaweed. It is found on both sides of the Atlantic and in the Mediterranean. It has a leathery texture and is sweet to the taste.

LAVER: purplish to red with a satiny sheen. It is found in abundance in the Atlantic and Pacific Oceans.

Plankton consists of minute plants and animals that drift around or swim weakly in the oceans. They can be caught by dragging a net through the water. Their taste depends largely upon the types of organisms that predominate in the area: if the population is mainly fish larvae the plankton will taste like fish; and like crab or shellfish if the population is mainly crab or shellfish larvae.

Plankton contains considerable quantities of protein, carbohydrates and fats. However, because it also contains chiton (molluscs with shells) and cellulose, plankton cannot be immediately digested in large quantities. If you are living solely on plankton, therefore, you must eat small quantities at first. In addition, you should ensure you have an adequate supply of drinking water: digesting plankton will use up your body fluids.

Each plankton catch should be thoroughly checked before you eat it: remove all jellyfish tentacles (be careful not to get stung), discard the gelatinous plankton (their tissues are predominantly composed of saltwater), and check for species that are spiny. If the catch contains large amounts of spiny plankton, you can dry or crush it before eating.

IMPROVISED RAFTS

Rafts are handy for river travel, and they can also used for short sea journeys, such as travelling between islands in the tropics. Some small rafts, such as the brush raft (see below), can be constructed very easily, though they are not recommended for long-range travel.

Rafts will not capsize easily if they are made properly, but you must remember the following points before setting out on your journey:

• Test your raft soundly in safe water before setting out.
• Tie all equipment securely to the raft or to the safety line. All personnel should also have a bowline (see Ropes and Knots Chapter) around the waist and secured to the raft.

When travelling by raft you must be aware of the following dangers:

SHARKS: sharks have been dealt with in detail above, but take care not to attract them to your raft by throwing waste into the water when they are around.

SALTWATER CROCODILE: found throughout Southeast Asia, it is a well known maneater. It lives in saltwater or brackish water and it is common near river mouths and along coasts, though it has been sited up to 64km (40 miles) out to sea. Normally around 4.5m (15ft long), it can be vicious and aggressive, especially females with nests. This animal can pose a great danger to you and your raft: keep a watch for it when you are landing or fishing.

CORAL: normally found in warm waters, along the shores of islands and mainlands. Try to avoid it: it can destroy a raft and injure its occupants. If this is not possible, try to steer the raft around it.

SHIPS: your raft is a very small object in a very large sea. Ships may have difficulty seeing it, especially in inclement weather or at night. Take care that you are not hit by a ship: have your signalling equipment ready.

Brush raft This flotation device will support around 105kg (250lb) if made properly. You will need ponchos, fresh green brush, two small saplings and a rope. First, tie off the neck of each poncho with the neck drawstring. Attach the ropes at the corners and sides of each poncho and ensure they are long enough to tie with the rope on the opposite corner or side.

Second, spread the poncho on the ground and pile fresh brush onto it until the stack is about 46cm (18in) high. Pull the poncho neck drawstring up through the centre of the stack. Make an X-frame of the two saplings and place on top of the brush stack. Tie the X-frame securely in place with the poncho neck drawstring. Pile another 46cm (18in) of brush on top of this.

Third, pull the poncho sides up around the brush and tie the ropes diagonally from corner to corner and from side to side. Spread the second poncho, tied-off hood up, next to the brush bundle.

Fourth, roll the brush handle onto the centre of the second poncho so that the tied side is down. Tie the second poncho around the brush handle in the same way to tie the first poncho around the brush.

Log flotation A flotation device for the single survivor. Fashion it out of two logs of light wood. Place the logs together about 0.6m (2ft) apart and tie them together. You will be able to float on them.

Vegetation raft This raft is made out of small vegetation that will float. Place the plants, such as water hyacinth or cattail, in material or clothing to form a raft for equipment or personnel (it will not hold heavy weights, though).

Bull boat This is a shallow-draft skin boat shaped like a bath. Construct an oval frame, like a canoe, from willow or other pliable wood. Cover this framework with skins or other waterproof material.

Log raft To make this raft you only need logs, an axe and a sheath knife. To carry three people it should be 3.6m (12ft) long and 1.8m (6ft) wide. The logs themselves should have a diameter of 30-35cm (12-14in).

Build the raft on two skid logs placed so that they slope down to the bank. Smooth the logs with an axe and cut two sets of slightly offset inverted notches, one in the top and bottom of both ends of each log. Make the notches broader at the base than at the outer edge of the log. A three-sided wooden crosspiece 30cm (12in) longer than the total width of the raft is driven through each end of the four sets of notches.

Complete the notches on the tops of all the logs, then turn them over and drive a three-sided crosspiece through both sets of notches on the underside of the raft. Complete the top set of notches and drive the additional crosspieces through them. When the crosspieces are immersed in water they will swell, resulting in the logs being tightly bound together.

If the crosspieces fit too loosely, wedge them with thin, board-like wooden pieces. When immersed in water they will swell and make the crosspieces tight and strong. You are advised to make a deck of light poles on top of the raft to keep equipment dry and a paddle to aid movement and navigation.

Lashed log raft If you have rope available you can construct a simple log raft. Use pressure bars lashed securely at each end to hold the logs together. The construction of this raft really requires two or more people because the gripper bars are under tension. If you are on your own exercise great care when making this raft.

BRITISH SBS TIPS:

LASHED LOG RAFT

The lashed log raft is relatively easy for two or more people to make and sturdy when completed. Here’s how to construct it.

• Place two thickish stakes on the ground and lay logs over them.
• Place two other stakes on top.
• Tie each pair of stakes firmly together on one side.
• With a helper tie the other ends together so that the logs are gripped between them, or use hardwood spikes to secure logs.
• Notch the ends of the gripper bars to stop the ropes from slipping.

Sea anchor A sea anchor can act either as a drag by slowing down the rate of travel, or as a means of travelling with the current. When the anchor is closed, it forms a pocket for the current to strike and will propel the raft in the direction of the current. When the apex of the anchor is opened, it will act as a drag and the raft will stay in the general area. Adjust your anchor so that when the raft is on the crest of a wave, the sea anchor is in the trough of a wave.

Rafting ashore If you are in a one-man raft, making a shore landing will usually present no difficulty. However, if the surf is strong you could run the risk of capsizing. In this situation you should sail around and look for a sandy, sloping beach where the surf is gentle.

Do not land when the sun is low and shining into your eyes, and avoid coral reefs and rocky cliffs (reefs do not occur near the mouths of freshwater streams). Do not make a landing at night: you will not be able to see any dangers until it is too late. Deploy the sea anchor to help prevent the raft capsizing, though don’t deploy it when travelling through coral. If the raft turns over in the surf try to grab hold.

Landings on sea ice sho uld only be attempted on large, stable floes. Stay away from icebergs, small floes and disintegrating floes.