Room Three, at Balclutha Primary School, asks :-
How do sea animals protect themselves?
Keith Probert, a marine scientist at Otago University, responded.
Sea animals may need to protect themselves against all sorts of things, from predators to possibly harmful conditions of where they live. Different fish, for instance, have a number of ways of trying to make sure they don't get eaten. They may have a tough skin, or be armed with spines. Some spines also have venom glands. Other fish taste nasty, or are even poisonous, so predators avoid them.
Making yourself hard to see is another form of protection, such as by changing your colour pattern to match your surroundings. Other fish mainly depend on being able to dart away from an enemy or finding a hiding place, such as a rocky crevice. For fish that stay in open water, being part of a large school can actually be a form of protection by making it hard for a predator to single out prey.
But it's not just other animals that can be a danger. If you live on a rocky shore you may need to protect against being damaged by crashing waves, or - when the tide is out - against drying up. So, as with limpets, having a shell and being able to cling tightly to the rock are important. Of course these also protect you against predators.
So sea animals have ways of protecting themselves much like other animals, such as by using armour, weapons, camouflage, hiding, being able to escape quickly, or confusing an enemy.
Maybe you could find out how clownfish, like Nemo, protect themselves.