The largest animals in the oceans, blue whales, reach a truly gigantic size - up to 33 meters, and these giants can weigh more than 150 tons. For comparison, let's say that 50 African elephants weigh the same amount. For its active existence, an animal needs 1 million calories every day. The blue whale belongs to baleen whales (genus whale whale); its typical diet is small fish, crustaceans, cephalopods, plankton and krill.
Finding such an amount of food is not difficult if you know where there are many crustaceans. In the so-called “feeding fields”, where the highest concentration of plankton, several whales can be seen at once, although they are usually not collected in more than 3 individuals in a group.
Blue whales are common throughout the oceans from the Arctic to the Antarctic, while there are several subspecies:
- northern;
- southern;
- dwarf;
- Indian.
The first two species prefer the cool waters of the ocean, while dwarf and Indian are found in tropical seas. Leading a solitary lifestyle, these mammals have developed their original way of communication. Sometimes adults form small groups, although even in such small communities they keep apart.
The large blue whale does not have a sensitive sense of smell, and is also practically deprived of vision, but it manages to communicate with the help of “singing”. Inviting sounds are made by males during the mating season. This singing is more like a terrible howl that can be heard at a distance of 1600 km. Females also sometimes communicate, but only with their cub. According to scientists, blue whales analyze the received sounds, since this is the only way for them to communicate with the outside world. In addition, the wit and intelligence of these animals are noted.
The breeding season occurs once every two years. It takes 10-11 months to bear the offspring. After the birth of the baby, the female feeds it with milk for 7-8 months, at the end of this period the weight of the young whale is more than 20 tons, and the length is more than 20 meters. At this time, part of the skin of the cub is already affected by marine parasites. The studies revealed a significant amount of internal and external parasites of the whale. During a stay in the feeding fields, an adult animal is covered with diatoms, which scientists have counted 31 species on just one whale. From this, the skin of the mammal becomes yellow-green, numerous mollusks live there, right on the body of the animal.
For many years, blue whales were exterminated by man. For the sake of catching a whalebone, fat and meat, a man hunted these giants, reducing the population by 100 times. At the beginning of the 20th century, uncontrolled fishing led to the fact that now on the planet no more than 1, 500 individuals remained. Scientists' forecasts are disappointing: this species can no longer be saved from extinction from the face of the Earth. There are currently no more than 100 adult whales in the North Atlantic.
Their extinction continues due to dumping of waste into the ocean, oil spills and active human intervention in nature. Too slow natural growth greatly inhibits the renewal of the population, and keeping in artificial conditions is impossible due to the size of the mammal.
