|
Animals of many kinds are found everywhere in the vast oceans. Some of the smallest animals live in the sea, as does the world's largest, the blue whale. Cod, halibut, seals, and whales swim the frigid waters of the polar regions. Lobsters, sea urchins, and many types of brightly colored fish inhabit coral reefs in warm tropical seas.
Some ocean animals live near the shore-in shallow water, in tide pools, and on rocks. They include anemones, barnacles, mussels, octopuses, and starfish. Other marine animals-mostly such tiny shrimplike creatures as krill and copepods-are found in the open sea. Krill and some species of copepods form part of the group of organisms called plankton. Many fish and some whales feed on plankton.
The great depths of the ocean are completely dark, and the water there is bitterly cold. Even so, anglerfish, clams, and certain other creatures live there. On the other hand, flyingfish, manta rays, marlins, and porpoises generally swim near the ocean surface. Albatrosses, gulls, and petrels fly above the sea.
|
Oceans provide people with such foods as crab, fish, lobster, and shrimp. However, the demand for seafood has led to the overfishing of halibut, herring, and some other marine animals. Millions of dolphins, which are mammals, have drowned in fishing nets that were intended to catch cod, tuna, and other fish. In addition, spills of toxic materials and other forms of pollution have reduced the numbers of some ocean species.
|
 |
