Sea animals that stay in one place their whole life. Some coral produce a colourful skeleton (which is also called coral) that will remain after they die. Coral are often found grouped in large areas called coral reefs, and they are related to sea anemones and jellyfish.
A long line of jagged rock, coral, or sand just above or below the surface of the ocean. An artificial reef is when a human-made structure creates a reef on the sea floor.
A prickly fish that puffs itself up to scare away predators by swallowing water or air. It is often poisonous.
Tiny living things (organisms) that drift and float in water. Plankton can be plants, animals, or other types of organism. They are an important source of food for large sea animals such as fish and whales.
An animal that feeds by sucking in water and filtering it to take out anything that can be eaten.