Sea otters: Not only cute, but also clean marine forest heroes

Sea otters are a type of marine mammal that lives along the northern and eastern coasts of the North Pacific Ocean. They are also the smallest marine mammals. Sea otters are mainly distributed in countries close to the North Pacific Ocean, such as Canada, Japan, Mexico, Russia, and the United States. Sea otters are relatively large in size and have relatively short tails. Sea otters are loved by people for their cute appearance and lively behavior. However, in addition to being ornamental animals, the role of sea otters in the marine ecosystem is far more profound than we know. They are not only an important link in the marine food chain, but also a key species in maintaining the balance of the seabed ecology.

Sea otters are veteran foodies in the ocean. Because they live in a relatively low-temperature ocean, they do not have much fat and can only stay warm by eating a lot. Sea otters feed on lobsters, abalone, shellfish, etc., but their favorite food is sea urchins. A sea otter can eat about 50 sea urchins a day. Sea urchins feed on algae. If there are too many of them, it will lead to excessive consumption of seabed algae, which will lead to the collapse of the algae ecosystem. Sea otters effectively control the number of sea urchins by eating a large number of sea urchins, thereby protecting the growth of seabed algae and maintaining the balance of the marine ecology. This behavior of sea otters is vividly called the "ocean forest ranger hero."

The shell of a sea urchin is very hard and cannot be opened by teeth. Sea otters have come up with a clever way: after catching a sea urchin on the seabed, they find a stone and hide it in the loose skin under their two front limbs. After swimming to the surface, they lie on their backs and put the stone on their chest and abdomen as a cutting board. Then they grab the sea urchin with their front limbs and hit it hard against the stone until the shell cracks and the meat is exposed. After eating, the sea otters hide the stone and the leftover food in their skin for later use.

The sleeping style of sea otters is also amazing. They usually choose to rest on the sea surface, and sometimes wrap themselves with kelp or seaweed to prevent drifting away in their sleep. With seaweed as a "safety rope", the sense of security is "off the charts"! If there is no seaweed in the sleeping place, the sea otters will sleep holding hands to ensure that they will not separate from each other. This unique sleeping habit not only shows the sea otters' ability to adapt to the marine environment, but also reflects their survival wisdom in nature.

To protect themselves from the cold waters of the North Pacific, sea otters have as many as 160,000 hairs per square centimeter. Sea otters usually spend a lot of time combing and licking themselves, including their fur, head, tail, and limbs. They even wash their chests and abdomens, which are the "dining table". Combing their hair can help sea otters remove dirt and parasites and keep their hair fluffy and waterproof, which is crucial for sea otters living in cold waters. If the fur is matted or stained with dirt, seawater will directly penetrate the skin, dissipating the body's heat and causing them to freeze to death. In addition, combing hair can stimulate the sebaceous glands to secrete oil, further enhancing the waterproof layer of the hair.

With the increase of human activities, the living environment of sea otters is under threat. The common name of sea otter fur is sea dragon skin, which is the most valuable of all furs. In particular, the hair in the middle of the back is 4 times denser than the mink fur, which is known as the "king of fur". Therefore, they were hunted on a large scale. By the beginning of the 19th century, there were less than 2,000 sea otters in the world. Although the number of sea otters has rebounded after the international ban on hunting sea otters was issued, the situation of sea otters is still not optimistic. At present, the IUCN still lists sea otters as endangered species. At the same time, due to operational errors, oil leaked to the sea surface or the beach will soak their fur and lose the ability to keep warm, and sea otters will die of hypothermia. As a marine mammal, sea otters not only attract human attention with their unique lifestyle, but also silently maintain the stability of the marine ecosystem. Therefore, it is particularly urgent to strengthen the protection of sea otters and their ecological environment. Only when we fully realize the important role of sea otters in the marine ecosystem can we better formulate protection measures to ensure that this marine forest protection hero can survive on the earth for a long time.

References:

[1] Lala. The wonders of sleep in the animal world[J]. Cover Story

[2] Xiao Feiyu. The sea otter who loves to comb his hair[J]. Art Code

[3] Si Qi. Sea otters have a clever way to reduce carbon emissions[J]. Miracle

[4]https://baike.baidu.com/item/%E6%B5%B7%E7%8D%AD/551922?fr=ge_ala