Do you need a fishhook? At a pinch, even a small pocket knife can become a hook for a large saltwater fish. Prop the blade partly open with a piece of wood and tie it in place. Use a smaller blade at the other end to form a barb.
For smaller prey, try a safety pin, wire, bent nail or even a paper clip. Or you can carve a hook from bone or hardwood, binding on a thorn or sharp sliver of wood for a barb.
