ANIMALS. ANIMALS. The marine biome covers three fourths of the earth and there are hundreds of different fish to cover each square foot of it. The main kinds of animals in the sea are whales, dolphins, sharks, and seals which are some of the most popular kinds of sea mammals.ther kinds of animals and fish that live in the sea are the walrus, star fish, eel, crabs, jelly fish, and fresh and salt water fish, but this is just a small list compared to the many different kinds of fish that inhabit the marine biome. In general these fish have about five different adaptations.