32 L4-All About Ocean Life

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Oxford Read and Discover level 4 All About Ocean Life by Rachel Bladon

Introduction A lot of Earth is covered by saltwater oceans. The oceans are home to many types of life, from the smallest plants to the biggest whales. What do you know about oceans? Which mammals live in the oceans? Which animals can you find in icy oceans? Discover! Now read and discover more about wonderful ocean life!

Chapter 1 Oceans of the World There are five oceans, and they cover about 70 percent (%) of Earth. Oceans and their seashores are different all around the world. On the Arctic Ocean and the Southern Ocean there's a lot of ice in winter. In warm tropical oceans you can find colorful coral reefs, where very many plants, fish, and other animals live. An ocean is always moving because of waves, currents, and tides. When the wind blows over the water, it makes waves. Currents are large amounts of warm or cold water that move around the ocean. An ocean also moves up the seashore and back again two times a day. These movements are called tides. Living in the ocean is very different to living on land. Ocean plants and animals have special ways of breathing, eating, moving, and keeping safe. Discover! The blue whale is the biggest animal in the world. It can be more than 30 meters long! It moves well in the ocean because the water holds it up.

Chapter 2 Who Eats What? In the ocean there are lots of very small animals and plants called plankton. The plankton live near the top of the ocean because they need sunlight. Small fish eat plankton. Big animals eat the small fish. Then even bigger animals eat them! So plankton are important for almost every ocean animal. This is called a food chain. Animals that eat other animals are called predators. The animals that they eat are called prey. Most sharks are predators. Sharks can swim very fast to catch their prey. Discover! The whale shark is the biggest fish in the world. It's as long as a bus. It has no teeth, so it only eats plankton and small shrimps. Lots of seaweed called kelp grows near the seashore. The kelp is a safe home for many fish. Sea urchins eat kelp, and sea otters eat a lot of sea urchins. So sea otters help to keep enough kelp in the ocean for the fish to live in.

Chapter 3 The Seashore There's a lot of ocean life near the seashore because the water here is full of food. Many birds, fish, and shellfish live and feed near the seashore. The seashore is not always a safe place. Big waves can throw animals onto rocks or carry them away. At low tide, animals and plants can easily dry out in the sun. Limpets are animals that have a special strong foot that holds onto rocks. This keeps them safe from big waves. They also have a hard shell so they don't dry out. Most trees can't live in salty ocean water, but mangrove trees grow on the seashore in tropical places. They have special roots so they can live in salt water. Many fish and other animals live under the roots of mangrove trees. Under the water, sea anemones use their long tentacles to catch food and to sting their predators. At low tide, they pull their tentacles in so they don't dry out.