Sponges, corals, and gorgonians living in a reef at the Florida Keys National Marine Sanctuary
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Courtesy of NOAA

Life in the Shallow Ocean

Many creatures make their home at the bottom of the ocean where the water is shallow enough for sunlight to reach them.

Where the ocean floor is sandy or muddy, you might find fast-moving crabs and slow-moving sea stars and snails. Some fish and sharks swim about just above the ocean floor. Other animals, like clams, worms, and sea urchins, live buried in the sand or mud. Sea grass, which looks like a lawn of tall grass, can also grow in here.

Where the ocean floor is rocky and water is cold, kelp forests can grow. In these places you will find large algae called kelp growing from the ocean floor all the way to the surface of the water. The kelp makes an underwater forest where many different animals live. You might find sea lions swimming between kelp in search of fish or playful sea otters eating urchins and molluscs called abalone.

In tropical, warm water coral reefs grow on rocky areas of the ocean floor. Coral reefs are named after coral animals. Reefs are full of hundreds of other types of animals and algae too. You can find lots of colorful fish swimming through reefs. On the surface of the reef you can find invertebrates like sponges, snails, sea fans, worms, crabs, and sea stars.

Last modified June 1, 2010 by Lisa Gardiner.

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