Is it possible to survive on a desert island?

There are many shows, movies, and books that have been based on the classic view of being stranded on a desert island. Images of people waking up on the beach after their ship wrecked and building a shelter are all too common in fiction, but if this ever happened to you how easy would it be to survive on a desert island and what would be the chances of making it back home alive?

(The classic image of the kind of desert island someone would be stranded on in a storybook, but In reality, you would last about 3 days until you died of thirst)

The answer would depend on several things, such as the size of the island and what equipment you had, but if you knew what you were doing then you would be able to survive on most of the islands bigger than an acre indefinitely. One of the best things about desert islands is that they usually have really good seafood that isn’t hard to catch, so long as you have the equipment and know how to use it. Many of the smaller tribal groups that live in very remote coastal areas have seafood as the bulk of their diets, but this fishing knowledge isn’t something that the average Westerner would know.

For some good examples of whether it would be possible to survive on a desert island, some of the true survival stories below might help.

Tom Neale – 16 years alone on an island

Tom Neale got bored with his life in New Zealand and decided he wanted to live in a place where people wouldn’t bother him. After finding an island called Suwarrow Atoll he instantly knew he wanted to live there, and built a small home for himself and lived there alone on and off for 16 years. He survived by creating a small garden but mostly living off the sea, which also provided red meat from marine mammals and sea birds.

Jack Renton – 8 years living with a tribe

Jack Renton was a sailor in the late 19th century who was kidnapped one night by another crew and forced to work onboard their ship as a slave. He was taken across the Pacific Ocean toward Indonesia until one night he realized he and the other slaves had a chance to escape. They quietly climbed on a rowboat after dark and set off into the night, hoping to be near one of the Solomon Islands. They made it to shore but the local tribe killed everyone except Jack, who only survived by showing them things he knew like how to make a proper fishing net. After he gained their trust he basically joined the tribe and lived with them for 8 years until a ship from Europe showed up and took him back home.

Alexander Selkirk – Stranded for over 4 years

Alexander Selkirk was the real-life inspiration for the story of Robinson Crusoe and managed to survive alone on an island for over 4 years. The island has since been named Alexander Selkirk Island and is just under 50 km2, which is big enough to home grazing mammals. besides some excellent fishing, the island had several small herds of goats which he was able to hunt, and plenty of fruit trees to give him a more varied diet. His main issue was trying to sleep without the local rat population trying to eat him, but he solved this problem by semi-taming a group of wild cats that lived on the island, and slept close enough to them so they would attack any rats that came close.

But would it be possible for the average person to survive on a desert island?

If that island was big enough to have a running source of water on it, then yes. The problem with tropical conditions is that drinking stagnant water is risking a death sentence or an intense illness in the best-case scenario. Collecting water using the large leaves you would find there would be useful, but if you do not have anything to store it in or you’re not there in the rainy season then 3 or 4 days later you’re dead.

(It may look like a nice place to get stranded, but it’s too small to have fresh running water and that’s going to be your number one concern on a desert island)

If you ever find yourself stranded on a desert island then survival would depend on the size of the island and its elevation. The higher up it goes, the greater the chances of a stream being present. Fresh water will be your number one concern and if it isn’t there then you’re not going to last long. There are methods of producing fresh water from salt water by evaporating it in a makeshift distillation device using bottles, or by trapping condensation using plastic sheeting in a pit dug on the beach, but these are far from perfect and also require certain materials you probably won’t have.

If water is present then shelter is going to be your next worry, because even tropical islands can get very cold at night, and being constantly soaked by the rain isn’t going to help anyone. Fortunately, tropical locations are the best in the world for making shelters, with materials like bamboo being unmatched when it comes to making a structure, and huge flat leaves making thatching much easier. In the tropical band of the earth, these things can be found almost everywhere, and forests in tropical zones contain a thicker concentration of plants than any other kind of environment.

(The ideal type of shoreline for a desert island, with plenty of rocks to catch seaweed and shellfish to hide under)

If you have fresh water then the size of the island doesn’t matter as much as what’s around it. If the shore and shallow areas of the water are smooth and void of rocks, then you’re in big trouble, but if you have huge patches of seaweed and large amounts of rocky outcrops then food shouldn’t be much of a problem. Foraging in these areas will almost always provide something to eat, but only if you are willing to grab it. Seaweed is also edible but certain types can make you ill, so make sure you recognise the type before cooking it.

The biggest killer when surviving on a tropical island after a lack of water is illness and infection.

(I was going to put a picture here of what a tropical infection looks like on a wound, but you might be eating something soon, so here’s a picture of a confused-looking tropical bird instead.)

The smallest of cuts can quickly become infected in the warm and humid conditions on a tropical island, and there are numerous stories of the early survivors dying from the tiniest of wounds after developing an infection they couldn’t cure. Before antibiotics, tropical areas were considered no-go zones for most Westerners due to the chance of them getting sick, and hundreds of explorers were lost in tropical conditions to illnesses they had never seen before. If you were stranded on a tropical island, you would most likely not have a full set of antibiotics and antivenoms with you, so even if the needs of food, water, and shelter could be easily met, then your life would still constantly be in danger.

How long would you have to survive before being rescued?

Assuming you were on a ship that got washed up on an island somewhere, and you didn’t have the means to call for help, a realistic answer would be no more than a few days. If someone knew you were missing then help would likely find you quite quickly, and even if no one knew you were on board the ship or plane then they would still be looking for the vessel itself. Today all international ships and aircraft have their journeys planned and logged before they leave, and when the owner finds out their vessel is missing or the expected delivery didn’t arrive at its port on time, then the standard search procedures will begin.

The other reason is that there are very few uninhabited islands left around the world, and the few that remain are normally close to ones that people live on or close to shipping routes. If you had the ability to light a fire then getting found would probably happen quite quickly, and anyone who travels as the crew on an international route is trained at how to recognize when someone is stranded.