A few Ocean Animals

Ocean Animal Facts for Kids

This web page contains ocean animal facts for kids and is an excellent resource for anyone of any age looking to learn about animals in the ocean. Our goal is to provide you with accurate, up to date facts about ocean animals. In addition to facts about ocean animal, we provide additional resources to help you with your research on these marine animals.

The ocean animal facts below will help you learn about the different kinds of ocean animal, how many ocean animals there are, where many of the ocean animals live and other ocean animal related facts. We hope these ocean animal facts are interesting and help you learn more about this group of marine species.

If any of the below ocean animal facts are inaccurate, please contact us and let us know.


23 Ocean Animal Facts for Kids

  1. Ocean animals are organisms that live in the ocean.
  2. Ocean animals are also referred to as marine life, ocean life or sea life.
  3. Ocean animals include animals, plants and other various organisms.
  4. The size of ocean animals varies greatly, some are microscope, while others are enormous.
  5. There are an estimated 230,000 known marine species. However, marine biologists believe there could be up to two million total marine species in the oceans.
  6. Some estimates claim over 99% of all living species are found in the ocean.
  7. Ocean animals first appeared between 3 and 3.5 billion years ago, the first land animals appeared around 400 million years ago. That means ocean life dominated the planet for about 3 billion years.
  8. Marine microorganisms include viruses, bacteria, archaea and protists.
  9. A few examples of marine microorganisms are cyanobacteria and Thiomargarita namibiensis.
  10. Marine aquatic plants include any species in the plantae kingdom that lives in the ocean.
  11. A few examples of marine aquatic plants are kelp and seagrass.
  12. Marine fish include gill-bearing aquatic craniate animals that live in the ocean.
  13. A few examples of marine fish are sailfish, mahi-mahi and the great white shark.
  14. Marine birds include any avian species that has adapted to a marine environment.
  15. A few examples of marine birds are penguins, pelicans and albatrosses.
  16. Marine mammals are ocean animals that live in the ocean and have lungs that obtain air from the surface.
  17. A few examples of marine mammals are whales and dolphins.
  18. Cyanobacteria, a marine microorganism, is one of the oldest known lifeforms. It’s estimated that cyanobacteria appeared around 3.5 billion years ago.
  19. The jellyfish, a marine invertebrate, is older than the dinosaurs. It’s estimated that jellyfish first appeared between 500 and 700 million years ago.
  20. The seahorse, a marine invertebrate, is the only known living animal species where the male gives birth to offspring instead of the female.
  21. The blue whale, a marine mammal, is the heaviest organism on the plant with an average weight of 121 tons.
  22. Neptune grass, a marine aquatic plant, is one of the oldest living organisms on our planet. There is a colony in the Mediterranean Sea near Ibiza, Spain that is estimated to be at least 12,000 years old.
  23. Ocean animals are found at all depths of the ocean, include in the Mariana Trench. The very bottom of the Mariana Trench is 36,037 feet. A snailfish was found and filmed in the Mariana Trench at a depth of 26,800 feet.

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Additional Resources on Ocean Animals