My Deep-sea Fishery

Advanced detection equipment does not work on jellyfish, so the process of investigating jellyfish by Chinese researchers is also difficult and tortuous.

Researchers can only take boats and go out to sea once every two months to study jellyfish with naked eyes and primitive methods such as fishing with fishing nets.

my country's scientific researchers achieved significant results in the study of jellyfish in 2011.

On July 21, 2011, the researchers set sail to inspect Jiaozhou Bay.

Jiaozhou Bay is located in the southern part of the Shandong Peninsula. It is a fan-shaped bay with an area of ​​390 square kilometers. During that investigation, researchers put fishing nets at three points in Jiaozhou Bay.

After putting the fishing nets, the research ship moved all the way. For every minute it traveled, four or five jellyfish appeared quietly on the side of the ship. Among them were the Xia jellyfish and the giant sand jellyfish.

But whenever everyone uses a simple fishing net to catch, the jellyfish often slips away before the net gets close.

Although jellyfish does not have a brain, each jellyfish’s fan edge is distributed with their most sensitive sensory organs. These sensory organs have the functions of ears and eyes. Whenever there is a storm from outside, it passes through the sea water. Infrasound, feeling the threat approaching, escaped early.

After three hours of hard work, the researchers pulled up two fishing nets one after another, but the results were not satisfactory. The nets inside the fishing nets were all scattered jellyfish.

The researchers are very strange.

At that time, it was the fish suspension period. It stands to reason that it was the time when there were most fish in the ocean, but it happened that a live fish could not be caught.

Later, after investigation, the researchers discovered that there were too many jellyfish in that sea area, which ate all the eggs of the local fish school, and the sea fish had a fault.

As for why there are so many jellyfish in that sea area, the explanation of the scientific researchers is that, firstly, the overfishing of fish by humans has made the jellyfish larvae, which were the objects of fish feeding, escaped the catastrophe, and a large number of jellyfish larvae survived and grew into adults.

The second is that as the number of fish in Jiaozhou Bay decreases, there are fewer natural enemies that compete with jellyfish for food, which provides opportunities for jellyfish outbreaks.

When the third fishing net was caught, the researchers found that there were still jellyfish and six large jelly-like objects in the net.

The local fishermen said that they have not seen such a large jellyfish in the coastal waters for decades, which is surprising.

Ten years ago, large-scale fishery research ships operated in the Yellow Sea and the East China Sea, and all they caught were marine fish, and jellyfish were rarely seen.

The survey found that in the great outbreak of jellyfish in my country, the three most common types of jellyfish are sea moon jellyfish, sand jellyfish and xia jellyfish.

"Brother Yang, are you really sure that these jellyfish can be eaten? I heard that this thing is dangerous." Fang Youqun lay on the ship's side, saying danger in his mouth. In fact, there was no fear in his eyes. This kind of seemingly weak, but in fact terrifying creature has no sense of fear at all.

"The danger is real. Jellyfish is one of the most ferocious carnivores in the world, and one of the most toxins in nature, but it is also true that it can be eaten. Now many restaurants around the world have specialized cooking. The chef of jellyfish or jellyfish." Xiang Yang said with a smile.

"The outbreak of jellyfish is caused by overfishing which reduces the number of natural enemies of jellyfish, but from a global perspective, some areas are not overfished, such as the Antarctic where we are currently located. The climate is severely cold. It is not a region with developed fishery resources, but also exists. With signs of a jellyfish outbreak, this is really strange." Xia Pengjie on the side thought.

"I don't know this, I have to ask those scientists who specialize in jellyfish." Xiang Yang smiled.

In fact, it is difficult for scientists to solve this problem.

With the continuous outbreak of jellyfish in recent years, many scientific research institutions and maritime universities have begun to pay attention to jellyfish.

In Xiangyang's alma mater, there is a speciality related to jellyfish.

In order to clarify the factors other than overfishing in the jellyfish outbreak, scientists have also established a laboratory that can control and simulate the marine environment, and selected the jellyfish that are most widely distributed in the world’s oceans. The moon jellyfish was used as the first batch of samples. Carry out breeding and observation.

The water moon jellyfish has four ring-shaped stomachs, and the gonads are located under the umbrella and corresponding to the stomach.

Usually, a pair of male jellyfish and female jellyfish can excrete 100,000 sperm and eggs. After being fertilized in the water, the fertilized egg sinks to the bottom of the sea, finds a hard thing to attach, and develops into a polyp.

The polyp is only two millimeters in size and is the larva of the water moon jellyfish.

But scientists discovered under the microscope that the polyp has a strong predator ability, and it can even catch an Artemia directly into its mouth.

According to relevant surveys, as long as there are polyps in a sea area, more than half of the zooplankton in the entire water area will be consumed by the polyps.

The emergence of polyps has greatly reduced the food for fish and has a great impact on the overall ecological balance of the ocean.

"The most annoying thing about jellyfish is that they have no brains. They don’t know that they are hungry and full. They eat all their lives. These foods are usually mainly plankton, supplemented by small fishes and shrimps. Sometimes they even prey on the same kind. The flood of jellyfish is devastating, and the blow to the fishing industry is absolutely devastating." Xia Pengjie said.

Xiang Yang nodded, "That's right, so since we have encountered these sting jellyfish, even if we are thankless, we must find a way to salvage some of them, not to mention that these sting jellyfish can be eaten, and the price is not cheap. "

Xiang Yang once saw sting jellyfish prey on moon jellyfish in the laboratory.

The usually beautiful and gentle sting jellyfish is like a white-haired witch when eating~www.readwn.com~ Its most powerful weapon is its tentacle. When it catches a prey, hundreds of stinging cells in each tentacle will quickly penetrate each other. The skin and flesh of the animal, and then immediately released the venom, which paralyzed the prey in a short time, making the prey completely unconscious, and can only be at the mercy of the jellyfish.

Xiang Yang had seen the ferocious side of seemingly gentle jellyfish, so Xiang Yang didn't dare to underestimate these jellyfish.

Xiang Yang looked at the surrounding crew members who had already put on protective suits and said: "When a jellyfish feeds, it will use stinging cells to stab the prey to death, some of which will be eaten, and more will sink to the bottom of the sea and be wasted. When you are salvaging jellyfish, you must never take off your protective clothing, you know?"

"Don't worry, Brother Yang, we promise that we won't let the jellyfish touch our skin." Fang Youqun said nonchalantly.

Xiang Yang frowned and said, "I'm not talking about preventing you from touching the sting jellyfish, but during the entire salvage process, you are not allowed to take off your protective clothing. The tentacles of the sting jellyfish can grow up to fifty meters long. The lethality is still strong at fifty meters away. As long as you don’t wear protective clothing, you will surely be caught no matter how careful you are."