Mary Allen
The blue whale is the largest animal in the world. Like all whales, it belongs to mammals. Its body can grow up to 33 meters long and weigh 200 tons. The heart of the blue whale alone weighs as much as a small car, namely 600 to 1000 kilograms. It beats a maximum of six times per minute, always pumping several thousand liters of blood through the body.
A blue whale versus a human and a dolphin.
Like other whales, the blue whale has to surface again after a few minutes underwater to breathe. He exhales a huge fountain called a blow. It rises up to nine meters high.
There are blue whales in all seas. They spend the winter in more southern areas because it is warmer there. They tend to spend the summer in the north. There the blue whale finds a lot of tiny crabs and plankton. Another word for it is krill. He eats about three to four tons of this per day and builds up large fat reserves from it. He needs these fat reserves for the winter. Because then the blue whale eats nothing.
The blue whale doesn’t grind its food with teeth, because it doesn’t have any. Instead, there are many fine horn plates and fibers in its mouth, which are called baleen. They work like a filter and ensure that everything eatable stays in the blue whale’s mouth.
When blue whales are in search of food, they swim quite slowly. You are then about as fast as a person who is walking. When migrating longer distances, they swim at about 30 kilometers per hour. Male blue whales usually travel alone. The females often form groups with other females and their children.
Blue whales become sexually mature at the age of five to six years. The blue whale mother carries her baby in her womb for about eleven months. At birth, it is about seven meters long and weighs about two and a half tons. That’s about as much as a very heavy car. The mother nurses her child for about seven months. It then measures almost 13 meters in length.