Shrimp do not have an internal skeleton but do have a hard exoskeleton (armour). This offers solidity and protection. The shell, however, cannot grow which means that the shrimp must shed it regularly in order to become larger (this is called moulting). The old armour falls off and a new, larger armour is created. The new, still soft armour is grown underneath the old armour. The shrimp fills itself up with water after which the armour cracks and falls away. It takes about six days before the new armour has become hard. The animal will pump the water outside again that it has sucked up after the armour is hard. The body of the shrimp will thus have become smaller. This gives the animal the room to grow. Most shrimp shed ten times before they are finished growing.
Shrimp can be found in large quantities around the whole world usually in coastal regions. More than two thousand species have been identified. They are mainly carnivores (flesh eating) that hunt small worms, snails, fish and shellfish. Only during the juvenile stage will the shrimp also eat algae. Shrimp usually hunt at night. During the day they will bury themselves into the sand and only their eyes and antennae will show above the sand surface.
Shrimp, in turn, are the favourite prey for fish such as whiting and cod. Fish can eat approximately half of the shrimp population on a yearly basis in the North Sea and the Wadden Sea. This is not a threat to the survival of the shrimp. The quantity of shrimp is so large (approximately 160 billion in the North Sea and Wadden Sea) that the species have no difficulty in surviving. Even the fishing done by shrimpers has little influence on the size of the population. Approximately 5% of the shrimp available is fished yearly.
