Zooplankton

Zooplankton are tiny animals that float in the ocean and in fresh water. Most are so small you need a microscope to see them. They cannot swim very well, so they drift with the water. Zooplankton eat phytoplankton and other small things.

Kinds of Zooplankton

There are many different kinds of zooplankton. Some are baby fish, crabs, or starfish that will grow bigger. Others stay tiny their whole lives. Krill are a type of zooplankton that look like tiny shrimp. Jellyfish are also a kind of zooplankton when they are young.

Life in the Water

Zooplankton spend their days hiding from fish in deeper water. At night they swim up to eat phytoplankton near the surface. This is the biggest animal migration on Earth and it happens every day. They are an important meal for fish, whales, and sea birds. Many ocean animals would starve without them.

Fun Facts

• Blue whales can eat up to 8,000 pounds of krill in a single day.
• Some zooplankton can travel the length of a swimming pool each night.
• Baby crabs and lobsters start life as zooplankton.

Did You Know?

The daily trip zooplankton make up and down in the ocean is the biggest movement of animals anywhere on our planet.