Should you be in a situation where you are desperate for water and can catch large fish, drink the aqueous fluid along the spine. Carefully cut the fish in half to get it and also suck the fluid from around the eyes.. Don't drink any of the other body fluids of the fish as they are rich in protein and fat and will use up your bodily water reserves in digestion.

 

Ration all water reserves.  Prepare to use between 2-8oz per person per day. If you are low on water do not eat, especially foods rich in protein eg fish and seaweed, these require lots of water to digest. Carbohydrates require less water to digest.  If you have to abandon a ship try and collect some carbohydrate rich food if you can before leaving the ship.