Animals that live in water are called aquatic animals. Some animals like whales and seal live in sea water. Other animals like crocodiles and frogs prefer fresh water.
Examples of animals that live in water:
Hippopotamus, crayfish, seagulls, penguins, crocodiles, seals, whales, bullfrogs, abalone, earthworms, bluebottles, dragon flies, mosquitoes, flamingos, octopus, crabs.