Building a Report: Sea Otters at Work

Sea Otters: Small Animals with a Big Job

1Many kinds of animals make their homes along the cold coasts of the northern Pacific Ocean. Seals rest on the rocks, seabirds dive for fish, and whales swim past farther out. One of the smallest ocean mammals there has one of the biggest jobs: the sea otter. This report explains how sea otters stay warm, how they find food, how they rest, and how they help the kelp forests where they live.

2Unlike seals and whales, sea otters do not have a thick layer of blubber to keep them warm. Instead, they depend on their fur. A sea otter's fur is thicker than the fur of any other animal. It traps a layer of air next to the otter's skin, and that air helps keep the cold water away. To keep their fur working well, otters spend a large part of each day grooming, rubbing and fluffing their coats.

3Staying warm in cold water takes a lot of energy, so sea otters must eat a lot of food. They dive to the sea floor to catch sea urchins, crabs, clams and snails. An otter can tuck its catch into a loose pouch of skin under its front leg and carry it up to the surface. Then it floats on its back to eat. To open a hard shell, an otter may set a rock on its chest and bang the shell against it until it cracks.

4Sea otters spend most of their lives in the water, and they even sleep there. To keep from drifting away while they rest, otters often wrap themselves in strands of kelp. Sometimes many otters float together in a group called a raft. A mother otter carries her pup on her belly, which keeps the baby out of the cold water while she floats.

5Sea otters also help the place where they live. Kelp is a tall seaweed that can grow in thick underwater forests, and many fish and other animals find food and shelter there. Sea urchins eat kelp. When there are too many urchins, they can eat their way through a kelp forest and leave the sea floor almost bare. Sea otters eat sea urchins, which helps keep the number of urchins down. With otters nearby, kelp forests have a better chance of staying healthy.

6From their thick fur to their clever use of rocks, sea otters are well suited to life in the cold ocean. By keeping sea urchins in check, these small animals do a big job for the kelp forest and every creature that lives in it.