Food and fire are next on your list for shipwreck survival. Fire is important for many reasons and provides the following:
Collect your wood -- you need tinder, kindling and larger sticks and logs. The tinder can be anything dry and small. The "hair" from palm tree trunks works well. If you have matches, use those to start your fire. If not, there are many other methods for starting one. You can read all about them in How to Start a Fire without a Match.

As a last resort, use a flare to light your fire. Once you've made your fire, keep it going. Build your signal fire, but don't light it -- it should be large and full of dry brush and palm fronds. Top it with green fronds to increase the amount of smoke, and light it as soon as you hear or see a plane or boat.
Aside from coconuts and fruit trees, the best opportunity for food will come from the ocean. There are toxic fish that can make you sick, so a good rule of thumb is to not eat the following:
Specifically, the following saltwater fish are toxic to humans:
If you don't have a fishing kit from your life raft, try your hand at spear fishing. Bamboo makes for a great spear.

Now you have a four-pronged fishing spear. Actually nabbing a fish is the tricky part. There are two different methods -- diving and standing. If you have good swimming skills, try diving first. It's easier to spear a fish against something, so head toward rocks. If you aren't a good swimmer, try to find a rock to stand on or simply wade into knee-deep water. Fish scare easily, so move slowly and deliberately.
Once you have your fish, cook it to improve the taste. You don't need a skillet or deep fryer -- all you need is a fire and some rocks for a primitive oven:
If the fish aren't biting, make a meal from slow-moving conchs and sea snails. The white meat inside the shells can be boiled or eaten raw. Sea snails are found clinging to rocks near the shoreline. Conchs are located in shallow waters and tend to hang out in sea grass.
In the next section, we'll learn how to make a primitive raft.
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