The whale swim slowly through the water with its mouth open, and thousands of tiny fish and plankton swim into it. But the whale can't swallow anything larger than a shrimp.
Whale are mammals, and so they can not stay under water for to long. They need to come to the surface to breathe after 10 to 20 minutes. Blue whales usually dive around 100 meters, but can reach a depth of 500 meters. When they come to the surface, they blow a wet stream 12 to 15 meters up in the air.
Blue whale are the loudest animals on Earth. Their call is louder than a jet, and travel for hundreds of kilometers in the ocean. They use their calls and songs to communicate with other blue whales. Fortunately blue whales are no longer an endangered species.