In the biological classification of living creatures, an unusual detachment. It includes animals of four submarines: ruminant, callouses, pigshaped and kitoancodont. The latter unites water mammals. Representatives of the Hippo family can live both in water and on land. The rest lead only a water lifestyle: guinea pigs, dolphins and whales.
Description and appearance of the Japanese whale
Until recently, scientists united a Japanese whale with a North Atlantic whale. But later they were divided into two different types due to the difference in the structure of DNA. Outwardly they are little distinguishable. However, Japanese larger sizes.
Japanese whale dark and big. The body length reaches 18.5 m, and the mass of an adult is an average of 60 tons. Males are inferior to females in size. Some females weigh 80 tons. Newborns usually 6 m in length and weighing no more than 1 ton. This type of whale does not have a dorsal fin. And the black tail fin is very wide. It contains a wide recess in the middle. Side fins are also large with pronounced phalanges. On the lower abdomen in the genital area there is a white spot. In each individual, it is different in shape and size. The large head of the animal is covered by the horn layer of the skin in the form of huge warts. The whales have a highly curved line of the lower jaw. Kit is able to produce two jets of water up to 5 m in height.
The habitat of the Japanese whale
Japanese smooth whale lives in the northern part of the Pacific Ocean. Its area extends from Okhotsk to the Bering Sea up to the Gulf of Alaska. Sometimes whales of this species can be found near the territory of Mexico, but they rarely swim here.
They are characterized by seasonal migrations. In the summer they walk the subcutaneous fat in the Sea of Okhotsk, near the Kuril and Commander Islands. In winter, migrate to the East Chinese and Yellow Seas. Here they are born. Females give birth to them near the coast of Japan and South Korea.
Food and lifestyle of a Japanese whale
The basis of the diet of a smooth whale is small crustacean. For example, copepods. Whales dive behind plankton into small depths: no more than 20 m. Are under water from 7 to 20 minutes. The surface is not shown entirely. Although sometimes they jump out of the water high.
Compared to other types of whales, Japanese does not differ in speed. He develops speed up to 7 km/h. This largely affected the reduction of its number in the XIX-XX centuries. The craftsmen called him “convenient”, since it was not difficult to catch a slowminded large whale.
Females are able to give birth at the age of 6 to 12 years. And give birth to one cub and extremely rarely. The interval between birth is 2-4 years. Pregnancy in a female Japanese whale lasts 12-13 months. At this time, future mothers are lost in separate groups. Although at the usual time, whales conduct a single existence or hold a maximum of 2-3 individuals.
In 1986, a moratorium was imposed on commercial whaling fishing. By this moment, a very large number of whales of various species were exterminated. The population of the Japanese smooth whale has not recovered until now. He is on the verge of extinction and appears in the list of endangered species of the Red Book.
In the midst of hunting for smooth whales (1839-1909.), according to unspecified data, Kitolov killed more than 30,000 individuals. Many whales were killed illegally and in subsequent years.
Now the total pollution of the oceans, the entry of animals into fishing nets and under the vessels of the vessels affect the reduction in the number of species. The total number of Japanese whales in the east of the Pacific and in the Sea of Okhotsk is approximately 500 individuals. In addition, their low birth rate does not allow whale population to fully recover.
- The Japanese smooth whale can live to a rather advanced age if it does not become a victim of an accident (for example, from a collision with a ship). Its age is estimated at 70 years.
- In the process of propagation of smooth whales, there is such a feature as competition competition. In almost all types, the rivalry of males occurs in the form of a battle among themselves. Smooth whales solve this issue peacefully. They swim behind the female, mating with her in turn. The father becomes the one whose spermatozoa will get to the egg faster and fertilize it.
- The princes of the Japanese whale weigh almost a ton. They produce a large amount of sperm to increase the chances of successful fertilization.
- The growths on the head and jaws of the whale are a keratinized layer of the skin. These formations are called Callocytes. They live whale lice in them. They also settle on the soft skin of the genitals and in the area of scars or wounds.
- Japanese smooth whale is listed in the MSOP list. In the Red Book of Eurasia, he appears as a dying. Keith hunting is punishable by a fine. Strict measures are needed to comply with this prohibition.