Although jellyfish are big, they can't stand collision and squeezing. At the initial stage of trial rearing jellyfish in the farm, due to lack of experience, jellyfish often hit the pool wall during the movement, resulting in incomplete umbrella edge and tentacles falling off. Moreover, although jellyfish have strong regeneration ability, under artificial conditions, the injured parts of jellyfish are easy to fester, causing systemic lesions, which is very unfavorable for a large number of artificial breeding.
There are many small fish and shrimps between the mouth of jellyfish and the tentacles of wrist. They live in harmony with jellyfish and share joys and sorrows. There is a kind of "jellyfish shrimp", which is parasitic on jellyfish and happens to be its eyes. Whenever there is an enemy, the shrimp will stab it and the jellyfish will run away immediately. Interestingly, each jellyfish has only one shrimp parasitic, and this "one-to-one correspondence" relationship is still a mystery to be solved.
Jellyfish are carnivores. It catches small creatures with tentacles, kills prey with stinging cells on tentacles and eats them.
The toxin in jellyfish stinging cells is very powerful. Experienced people should always be careful of jellyfish when swimming in the sea. Once stung, the skin is red and itchy, and when it is serious, it will be poisoned and unconscious, which is very dangerous.
Jellyfish are widely distributed in China, from Liaoning in the north to Hainan in the south, and the coastal areas of Zhejiang produce the most. Jellyfish is one of the main aquatic products in China because of its delicious taste and rich nutrition. At present, there are only 4 species of jellyfish in the world, and China accounts for 3 species, namely jellyfish, spotted jellyfish and jellyfish. Fresh jellyfish can cut its umbrella and wrist with a knife, and the umbrella is the "jellyfish skin" sold in the market. However, fresh jellyfish should not be eaten immediately, because the newly caught jellyfish contain toxins in their umbrellas and tentacles and must be treated with alum before eating.