When it comes to seals, I believe everyone will be familiar with them. Like walruses, they are all flippers, but the two hind flippers of seals can only bend backwards, so they can only crawl on land.
Seals spend most of their time in the sea. Their bodies are spindle-shaped and have short hairs all over their bodies. Their forelegs are shorter than their hind feet, and there are nails on these flippers. Seals also have ears, but their ears have become very small and can be opened and closed freely when swimming. They are good at swimming, and their hind feet are like divers’ fins, which can swing back and forth in the water and move forward quickly. Seals dive for a long time, usually up to more than half an hour. When diving underwater, their heart rate will drop very low, which can reduce oxygen consumption.
Most seals live in cold waters, but they are not afraid of the cold, because they have a thick layer of fat, so seals usually like to live in places with ice in the North or South Pole. Seals also live in some sea areas of China, such as Bohai Sea. These sea areas freeze every winter, especially in Liaodong Bay and ice period for 130 days. These thick ice layers are inaccessible, and seals thrive here, the most of which are spotted seals.
These spotted seals are small, generally only 1.5 to 2 meters long. The maximum weight of males is 150 kilograms, while females are slightly smaller, about 100 kilograms. Their biggest feature is that their backs are covered with irregular brown-gray or brown-black spots, hence the name of spotted seals. They are very cute, so they are also permanent residents of the aquarium.
In the seal society, polygamy is practiced, so the number of wives and concubines usually depends on the male seal’s own physique. In order to compete for females, males often fight. Seals fight a bit like sumo. They use their hind legs to support themselves and try their best to pounce on each other. Sometimes seals will bite each other’s fur and blood will flow. At the end of the battle, the winner wins the right to mate, while the loser can only continue to look for the next female seal.
In early spring, baby seals will be born. At this time, we can see a young seal lying next to the female seal, which is very interesting. The young seal is raised by both parents, and the female seal is fed several times a day. Of course, the mother seal will only breast-feed her baby. If other baby seals come near, they will be rudely driven away. Some people may think that the mother seal is selfish, but this may be the law of nature.
The fat content in seal milk is very high, so baby seals will grow very fast. Young seals don’t have a thick layer of fat, but their hair is very fluffy and soft, and baby seals rely on these hairs to keep warm. But fluffy hair makes it inconvenient for them to swim, so baby seals rarely go into the water during lactation. Most of the fur of baby seals is white. From a distance, it is like snow, which is not easy to be found. They are not afraid of the cold and live a very leisurely life.
The lactation period of seals is not long, especially spotted seals, which only lasts for one month. After lactation, the mother seal will become skinny, and they will leave their children to recover. At this time, the seal family will end and the baby seal will begin to live independently in the water.
The leathers of seals are tough, comparable to cowhide, and can be processed into purses and leather shoes. Their thick fat can extract oil, and their meat is edible and has high nutritional value. In addition, the testicles of male seals are valuable Chinese herbal medicines, which have the effects of enriching blood and strengthening yang, and their livers are valuable tonics. Seals are all treasures, so they have always been the target of human hunting. Every spring, seals go ashore. In the 19th century, many countries used well-equipped ships to catch seals in the Antarctic, among which the crab-eating seals were the most caught. These hunting teams kill seals like crazy, and they can get tens of thousands of leopard skins from South Georgia in just one season.
Before the 1980s, fishermen along the Bohai Sea in China also had a tradition of killing spotted seals, but later legislation prohibited the killing of spotted seals, and now the population has recovered. In 2009, EU legislated to ban the trade of seal products, and Russia also banned the commercial seal slaughter.