Jellyfish, an ancient creature that has existed for at least 600 million years, can be said to be a very peculiar creature on the earth, they have no brain, no heart, no bones and muscles, its body is only a double-layer structure, just like a plastic bag (cortex) in another plastic bag (stomach layer), and the middle of the two layers is glued by gel-like glue (medium gel layer), more than 95% of which is water, and the rest is composed of proteins and lipids.
Seemingly "harmless to humans and animals", they are also a hegemon in the ocean, zooplankton, shrimp and fish are the prey of jellyfish.
How are jellyfish hunted? Most jellyfish have long, soft tentacles that are covered with spiny cells. The spine cells on the jellyfish tentacles are tiny and contain the stinger sacs that store the stings. When the spine cells are physically stimulated, a small number of stinging cells release the spines in the stinger sac and shoot at the prey in a very short period of time.
The fluids oozing from the prey after being stabbed will stimulate more spiny cells to emit spiny filaments through chemical reactions. The stingra will inject the jellyfish's venom into the prey, paralyzing the prey. Finally, jellyfish tentacles roll the prey into their mouths for chemical digestion, and a full meal is given to obtain the energy needed to survive.
Although most jellyfish are not large, there are also large jellyfish, such as such a jellyfish, which is difficult to ignore. It's the big Mac of jellyfish, nomura Jellyfish.
This is a giant jellyfish, generally more than 1 meter in diameter, and some individuals even reach 2-3 meters, which is the largest jellyfish in the world.
Echizen jellyfish contain toxins that affect the cardiovascular system of poisoned organisms. For fishermen, accidentally catching Echizen jellyfish is not a happy thing.
This is so because fishermen's entire day of fishing is wiped out by the intrusion of this jellyfish. Fish that fall into the net with jellyfish are either poisoned by jellyfish venom, and Echizen jellyfish with a water content of nearly 99% are difficult to use, and their large bodies will also crush the nets, which is why the original fishermen's method of dealing with Echizen jellyfish was only to chop and throw them back into the sea.
And this practice is like letting the tiger return to the mountain. Because once the jellyfish is physically damaged, they will strive to produce offspring to continue the gene, in which the female jellyfish ovary will mature rapidly, the egg cells will become larger and accumulate yolk material, and they can lay eggs in 3 to 5 days. Male Echizen jellyfish likewise allow their sperm nests to mature and release sperm.
The life of a jellyfish is divided into two stages: the hydra body (juvenile) and the jellyfish body (adult), just like the caterpillar transforms like a butterfly. Different jellyfish breed differently, the common sea jellyfish, after laying eggs will grow round floating wave larvae. Floating wave larvae develop into hydrates. The germination of the daughter-in-law continues to form new daughter-in-law, and the number of individuals can increase by dozens of times or more in a few months. These hydrangeas then evolve into jellyfish, and sometimes they develop into baby jellyfish with butterfly-like larvae, and finally into individual jellyfish.
But the Echizen jellyfish is different, it is through the foot sac to multiply the hydra body. As a result, asexual reproduction is slower, but an Echizen jellyfish develops an average of 4 hydra bodies per fertilized egg, and each hydra body can develop into a transverse fissure with an average of 5 discs. Normally, a single Echidna jellyfish can release 100,000 fertilized eggs, which eventually evolve into billions of hydra bodies. When the hydra body grows further, a stack of small jellyfish will split out one by one, and the final number will reach tens of billions. Therefore, after being chopped up by fishermen, it will promote the explosion of Echizen jellyfish.
At the same time, Echizen jellyfish are not without natural enemies. In order to maintain this size, the 100 kg Echizen jellyfish has to process 4260 cubic meters of seawater per day to eat the phytoplankton in it. This amount of water rivals the water volume of a standard Olympic swimming pool.
Therefore, the fishermen can only shake their heads helplessly when they see these Echizen jellyfish, and there is no solution at all.
These large outbreaks of Echizen jellyfish can be said to have caused great disturbance to human life, with their huge bodies, they will overturn fishing boats, on November 2, 2009, a 10-ton fishing boat recently overturned while operating in eastern Japan' waters, dozens of jellyfish fell into fishing nets, the excessive weight of the fishing boat overturned. Three crew members fell into the sea.
Once there is a major eruption of Echizen jellyfish, the fishing industry is destroyed. In Hachinobu Port in Aomori Prefecture, Japan, autumn salmon catches in the peak season are cut in half compared to last year, and at Misawa Fishing Port, halibut catches are 60% lower than in the same period last year. The impact of the "big outbreak" of mother-in-law jellyfish on the fishery can last for nearly a year at the longest.
Many nuclear power plants will be built on the seashore because the generator sets need a lot of seawater to cool to prevent the motor from overheating and damage. But wherever there is seawater, there is a chance of being invaded by jellyfish. In 2006, echizen jellyfish flooded into Japan's nuclear power plants, blocking the seawater filter holes in their cooling systems, posing a serious threat to nuclear power plants, and in addition to nuclear power plants, they also blocked the water intakes of coastal power plants. In July 2009, a jellyfish disaster occurred at a power plant in Qingdao, due to the influx of a large number of jellyfish in the water intake of the seawater pump room, workers continued to clean up around the clock, and finally, a total of 10 tons of jellyfish were cleared in three days. This jellyfish invasion incident has caused a great impact on the electricity consumption of Qingdao residents and industries.
The unfortunate news is that as the global climate gradually warms, some of the nearly 2,000 species of jellyfish have expanded their range of activities, not only appearing earlier each year, but also increasing in overall numbers. According to expert statistics, since 2000, what was originally a 40-year jellyfish outbreak has become an annual occurrence around the world.
The increasing number of jellyfish in the ocean has threatened the survival and human activities of other marine life, causing the death of a large number of other marine life, making the originally vibrant bay a "death zone". According to the National Science Foundation report, there are about 150 million jellyfish injuries worldwide each year.
In addition, the rapid development of human society, the production of a large number of industrial and domestic garbage, sewage caused by the excess nutrition of the ocean more and more, so that algae plants flooded, red tide, moss popular, so that algae plants for plankton to provide sufficient food, plankton multiply, plankton for food jellyfish, began to run rampant.
It can be said that it is human beings themselves who have broken the marine food chain.