The May Day Golden Week is coming, and I believe that many friends will take catching the sea as an important choice for travel. However, when you are at sea, you may sometimes encounter some dangerous creatures that you don't know.
Not long ago, when several tourists were playing on a beach in Wencheng Town, Wenchang City, Hainan, they found more than 20 jellyfish as translucent as plastic bags, and their body color was still beautiful blue, but then some experts reminded that these beautiful little jellyfish were poisonous monk's hat jellyfish, and they should not be touched at will.
When we play at the beach, we may encounter many inconspicuous or seemingly beautiful and cute creatures, but we don't know what is terrifying. Let's start with the monk's hat jellyfish, and take you to identify several common "poisons" that haunt mainland beaches, so as to help you spend a good time catching the sea safely.
01 Mitral Hydro
The monk's hat jellyfish is widely distributed in the tropical and subtropical waters of the Pacific, Indian and Atlantic Oceans, and is also distributed in the East China Sea and the South China Sea on the mainland, such as Hainan mentioned in the news, as well as the coasts of Liangguang and Fujian, there is a probability of encountering it.
The monk's hat jellyfish is still relatively easy to identify, it belongs to the order of tube jellyfish of the class of hydras, and most of the jellyfish we are familiar with, such as the moon jellyfish, jellyfish, etc., all belong to the class of the jellyfish (appearance characteristics: the jellyfish body has an umbrella-shaped or bowl-shaped umbrella cover and multiple tentacles around the mouth), its "appearance" is different - there is no umbrella cover like the bowl jellyfish, but it has a gas-filled top sac formed by a special polyp at the top.
Monk's hat jellyfish on the shores of Pahala in Fuerteventura (Image source: Wikipedia)
The "plastic bag-like" that tourists see is the pouch of the monk's hat jellyfish, which does not have the ability to swim actively, relying on this pouch to float on the surface of the warm ocean, drifting around with the current, but sometimes being washed up on the beach by the waves, the name "monk's hat" comes from the shape of its pouch.
The venomous toxicity of the monk's hat jellyfish comes from the tentacles under its pouches, which usually contract under the puffy sacs, and can stretch up to 10 or even 30 meters long when hunting, and are covered with poisonous stinging cells. If a swimming human accidentally touches the tentacles of the monk's hat jellyfish, they will also be stung by its stinging cells, leaving slender red and swollen wounds on the skin like whip marks, causing severe pain like fire or bee sting, and may even lead to severe allergies and even life-threatening.
Therefore, if you see a beautiful blue "plastic bag" floating on the surface of the water while swimming, do not go near it, and the swimsuit can also prevent being stung by the tentacles of the monk's hat jellyfish to a certain extent. When you encounter a monk's hat jellyfish washed ashore by the waves, do not touch or pick it up with your bare hands.
Fortunately, most of the monk's hat jellyfish distributed along the coast of the continent are smaller in size and less toxic than their close relatives in the Atlantic. concentrated acetic acid solution) to infiltrate the wound, and then soak the wound in hot water at 45 degrees Celsius for 45 minutes, the slender tentacles of the monk's hat jellyfish are very easy to break, and the broken tentacles may still attach to the victim and continue to sting, the above measures can kill the stinging cells on the severed tentacles in the shortest possible time to avoid further injury, and after the initial treatment, you should go to the hospital for treatment as soon as possible.
02 The "distant relatives" of the monk's hat jellyfish
Those distant relatives who belong to the same subphylum of jellyfish as the monk's hat jellyfish, their tentacles are also densely covered with poisonous stinging cells, if accidentally touched, they may be stung, and the species that are more likely to hurt people in the mainland are jellyfish and jellyfish genus, both types of jellyfish jellyfish are larger, and severe stings can lead to systemic symptoms and even fatal. Therefore, when swimming in the sea, you should try to stay away from any kind of jellyfish, and do not touch and pick up jellyfish stranded on the beach at will, especially pay attention to avoid the tentacles around its mouth, if you accidentally come into contact with a large number of jellyfish tentacles and cause serious puncture injuries, you should rush to the hospital for treatment as soon as possible.
霞水母属(图片来源:Wikipedia)
Jellyfish at the Monterey Bay Aquarium (Image Credit: Wikipedia)
Some species of sea anemones, which are cnidarians like jellyfish, are also capable of stinging people's skin, so don't touch them with your hands when you encounter any kind of anemones while visiting the beach, especially the larger ones.
03 Marine fish with poisonous spines
Some marine fish with venomous fin spines may also stab humans and cause poisoning and even life-threatening. The dorsal and pectoral fins of fish of the sea catfish family and the eel catfish family, as well as the dorsal fin of the fish genus (commonly known as "fox", "mud meng", "golden valley", etc.), money fish (commonly known as "golden drum") and suborder (commonly known as "Shi Jiugong", "lion fish", etc.) have sharp fin spines and venom glands, and if people are accidentally punctured, they will cause redness, swelling, severe pain and even more serious poisoning reactions.
(1) Sea catfish and eel catfish
The shape of the sea catfish family is similar to that of catfish or yellow catfish in freshwater, and the fin spines of its pectoral fin and dorsal fin are poisonous, and the eel catfish that also belongs to the order of catiformes has a slender tail like an eel, and the overall appearance is like a large tadpole, and the more common in the mainland is the linear eel catfish, the body is black on the back, and there are two yellowish-white longitudinal stripes on the side of the body, and they often swim in groups, and their fin spines are more toxic than those of sea catfish. Both are found in the East China Sea and the South China Sea, and their stab wounds can also cause severe pain and cramps for a long time, so if you catch these two types of fish while fishing, you must take care to avoid stab wounds, and if the stab wounds are severe, you need to go to the hospital for treatment to avoid wound infection.
线纹鳗鲶（图片来源：Wikipedia）
(2) Blue fish
Including many common edible fish (such as the brown blue fish commonly known as "mud fierce" and "stinky belly", commonly known as "Jinguman" and "Hua Nimeng") and marine ornamental fish (such as the fox blue fish commonly known as "yellow fox"), it is more common in shallow seas and harbor estuaries with many reefs in the South China Sea and the East China Sea. The dorsal and anal fin spines of the genus Blue Fish are poisonous, and although the toxicity is not as severe as that of the eel, it can also cause pain and redness.
A school of juvenile brown blue fish in Longdong Bay, northeast of Taiwan, grabs algae on a reef in shallow waters. Brown blue fish have a yellowish-green body color when they are young. (Image source: Wikipedia)
Started blue fish (Image source: Wikipedia)
狐蓝子鱼（图片来源：wikipedia）
(3) Money fish
Commonly known as the "Golden Drum", it is common in the shallow coastal waters of the South China Sea and the southern part of the East China Sea, harbors and estuaries, and also enters fresh water, and is often raised as an ornamental fish because of its elegant body shape and beautiful body color. Like the blue fish, the dorsal and anal fins are also poisonous, and stings can also cause severe pain and redness, and if caught, they are treated in the same way as the blue fish.
金钱鱼（图片来源：wikipedia）
(4) Poisonous Fish (Stonefish, Tigerfish)
The most dangerous of these ray-finned fishes with poisonous spines are members of the genus Poison Fish, which are commonly known as "stonefish" and "tiger fish" along the southern coast of the continent It is not good at swimming, and often relies on its body shape and protective color very similar to the reef in the sea to hide in the seabed and intertidal zone of the shallow sea near the shore, preying on small fish and invertebrates, which is difficult to find even if you look closely; the first dorsal fin of the poisonous fish has 12-14 sharp fin spines that connect to the venom glands, if a person accidentally steps on the poisonous fish when swimming or wading, it is easy to be stabbed by it, its venom will cause severe pain, convulsions, paralysis and local tissue necrosis, and can also cause breathing difficulties and destroy the blood circulation of the human body, and in severe cases, it can even be fatal, and there have been records of poisonous fish wounding people to death in Australia and Japan。
In mainland China, it is only distributed in the South China Sea, along the coasts of Liangguang, Fujian and Hainan. When wading between the reefs by the sea, you should wear slippers or water shoes, avoid going barefoot in the water, and if you are accidentally stabbed by a poisonous stinger, you must go to the hospital for treatment as soon as possible.
玫瑰毒鲉（图片来源：wikipedia）
（5）魟
This is a class of cartilaginous fish that can stab humans, also known as "manta rays", with a large, flat body and an elongated tail, often swimming on the ocean floor in a wavy movement of pectoral fins, or burying in the sand. With one or more large, sharp fin spines on the tail and numerous backward curved serrations at the edges, the surface of the fin spines is also covered with mucus mixed with toxic secretions, and puncture wounds can cause huge penetrations and lacerations, causing severe pain, swelling, and muscle spasms, which can lead to more serious or even fatal consequences if the puncture hits vital organs or large arteries.
短尾魟（图片来源：wikipedia）
In 2006, Steven Irwin, a well-known Australian crocodile hunter, died when he was impaled through the chest by a giant short-tailed stingray while filming a show, and in 2018, a man in Taoyuan, Taiwan Province, mainland China, died after being stabbed in the arm by a red stingray, which often causes serious bacterial and fungal infections in the later stages.
Common stingrays on the mainland include red stingray, yellow stingray, etc., which are distributed in the South China Sea and the East China Sea. Like poison fish, stingrays do not take the initiative to attack humans, stabbing human accidents are often because people wading in the water fail to find the stingrays lurking in the sand, accidentally step on them, or be caught and disturbed, out of self-defense, and prevent poison fish, in the water infested with stingrays should avoid going barefoot in the water, if you see a stingray, do not chase and tease, to avoid it hurting people. The dorsal fin of the tiger shark family, which also belongs to the cartilaginous fish family, also has poisonous fin spines, although it is not as dangerous as the stingray, and stabbing can also cause redness, swelling and severe pain, and if you encounter or catch it, you need to take care to prevent stinging.
赤魟（图片来源：wikipedia）
Finally, I wish you all a happy May Day holiday in advance!
Author: Hu Kai Science Popularization Research Tutor, Scientific Consultant of CCTV-9 Documentary Channel
Review: Liu Qinghua, Researcher, Institute of Oceanology, Chinese Academy of Sciences
Producer: Popular Science China