The Wildlife Trusts has released these pictures as part of a campaign to clean up UK seas. This hermit crab has an anemone living on its back that protects it from predators.
Starfish spit their stomachs out when feeding and digest their prey outside their bodies. If threatened they can bite off their stomach for a quick get away and grow a new one later!
This fish is a cuckoo wrasse. Females are orange and males neon blue. All cuckoo wrasse are born female, but they can sometimes change gender - and colour - when they're older.
Sea squirts eat their own brains! They're born as tadpole-like creatures, but once they grow up they become simple filter feeders - and eat their brains because they don't need them.
This ugly creature is a wolf fish. They have fangs to help them crack through the sea snails and crabs that they eat.