If you were asked what is more expensive in the world, I believe many people would think of gold first. Throughout the ages, gold has always been a symbol of preciousness and wealth, and now the price per gram of gold is about 400 to 500 yuan, equivalent to 400,000 to 500,000 yuan per kilogram. However, there is now a fry whose price has reached a level comparable to that of gold, hence the name "soft gold in the water".
"Soft gold in the water"
Since this fry can only be harvested from the wild at present, the huge profits have attracted many people to take risks and carry out illegal fishing activities. According to the Global Network, every year in the middle and late May of the Qiantang River, there is always a group of people who do not hesitate to test the law by themselves and risk their lives to "earn a vote". These people often use blue and white lights, which seem quite mysterious in the late night riverside. Originally, blue light was used to attract fry, and white light illuminated fry in order to "catch the net". Their target is the aforementioned "soft gold in the water" - Qiantang River eel fry.
Since it is a closed period, it is of course illegal to catch eel fry on the Qiantang River. But these people do not hesitate to risk being caught, and they take advantage of the early morning tide, because the night tide is relatively large and there are more eel fry rushing up. According to a police officer, some bold people will also run to about 100 meters from the shore to arrest, and if they are not careful, they will lose their lives.
Illegal fishermen venture into the water to catch eel fry
Due to the small size of the eel fry, illegal fishermen use a particularly small mesh net, and the smallest mesh size measured is only 3.8 mm, which is obviously a rhythm to exterminate the eel fry. According to reports, during the fishing ban period, the Hangzhou police have arrested 39 criminal suspects who poached eel seedlings. Why do so many people risk being caught fishing illegally? It turns out that they are tempted by high profits, to what extent?
It turned out that a 5 cm long, 0.1 gram Qiantang River eel seedlings could be sold for 50 yuan this year, and 100 pieces was 5,000 yuan. If you can catch 1 kilogram, you can sell for 500,000 yuan, which is already comparable to the price of gold. So what makes the price of eel seedlings so high? This has to start from the special life of the eel seedlings.
Captured Qiantang River eel fry
Eel fry, as the name suggests, are the fry of an eel. Eels are also known as eels, other names are white eels, white eels, river eels, brook slides, green eels, Japanese eels, etc., is a species of fish in the eel family, eels. Its body is long striped, with no ventral fins and no pectoral fins, and the dorsal fin and tail fin are joined together, so it looks like a snake. Because the tiny scales are buried under the skin and are often covered with thick skin mucus, it seems that there are no scales.
Eels are migratory fish that live in bordering waters of brackish waters. Except for the European eel and the American eel, which are distributed in the Atlantic Ocean, the rest of the species are distributed in the Indian and Pacific Ocean regions, especially in the western Pacific freshwater basin between Hokkaido and the Philippines in Japan, including large and small rivers and streams that flow into the Pacific Ocean such as islands and the Asian continent. In the mainland, it is distributed along the Bohai Sea, the Yellow Sea, the East China Sea, the South China Sea and its rivers, including the Qiantang River.
Adult eels
Eels are carnivorous fish, feeding on snails, clams, crabs, shrimp, copepods and aquatic insects, and are quite fierce. Since its fry are so valuable, you can guess that adult eels have extremely high economic value, weighing up to 300 grams, the longest can reach 1.3 meters, weighing up to 5 kilograms. And its meat is naturally very tasty.
As a high-grade edible fish, eel is a valuable export fish species that is exported to Japan in large quantities. Eels are tender and delicious, and they are rich in protein and fat, and have high nutritional value. Eels can be eaten fresh, smoked, vinegared, canned, and the skin can be made into handicrafts. Coastal folk often use it as a tonic food, which is one of the important objects of freshwater aquaculture.
Grilled eel sushi
In general, the price of what can be farmed will be much lower than that of the wild. Since eels can be farmed, why are they so expensive? The reason is very special: eels can be farmed from fry to adult fish, but its fry must be fished in the wild, and no more mature way to breed eel fry has been found. In other words, only if a wild eel fry weighing 0.1 grams is caught, it is possible to raise a commercial eel of 150 to 200 grams, which directly leads to the eel fry being able to sell for a sky-high price!
Eels can be farmed, but eel fry can only be caught in the wild
Why can't eel seedlings be artificially bred now? This is mainly related to its special reproductive habits and growth history. Eels are migratory fish that spawn in the deep sea and grow into adults in freshwater, as opposed to some other migratory fish. For example, salmon, trout, etc. spawn in fresh water, hatch and then return to the ocean to grow. In addition, eels go through several very different stages from fish eggs to adults.
The question of where eels spawn has been a mystery for a long time. It wasn't until the 1990s that the spawning grounds for Japanese eels were found: thousands of kilometres away, in the deep sea between the Philippines and the Maina Islands, and scientists discovered the spawning grounds mainly because of the many newly hatched hatchlings.
Eel migration route
Adult eels swim from freshwater rivers back to spawning grounds in the deep sea, no longer eating during migration, gradually degenerating their digestive organs and further developing their reproductive glands. A female eel lays about 7-10 million eggs, and the adult dies of exhaustion after spawning.
Eels have oil balls in their fertilized eggs, which float and develop with the currents after they are produced, and can hatch baby eels with a length of about 6 mm in 10 days, and then increase in body length. Eel seedlings of this period are transparent, flattened and shaped like willow leaves, so they are also called willow leaf eels.
Willow leaf eel
The shape of the willow leaf is conducive to drifting with the waves, allowing you to drift long distances with the currents in the sea. When they approach the waters along the land coast after a long drift, the body transforms into a streamlined shape, which reduces resistance in order to escape the strong ocean current, which is now called glass eel. After entering the estuarine waters, the body of the glass eel begins to appear melanin, like a line, so it is called an eel line. Eel lines are eel fry that are heavily caught.
Eel seedlings
At this time, the eel seedlings are about 5 to 6 cm long and weigh about 0.1 g. After that, the eel will grow and develop in fresh water, and the belly of the fish will appear yellow, called yellow eel. When it finally matures, the body color of the fish will change to a silvery white similar to that of deep-sea fish, while the eyes will become larger and the pectoral fin will be widened to adapt to migrating to the deep sea to spawn, at which time the eel is called a silver eel.
Due to the high economic value of eels, long-term fishing has led to sparse and expensive production of wild eels. Moreover, wild eels grow relatively slowly, reaching 150 grams after entering the estuary for four years. So people began artificial breeding, and the farmed eel fry could reach the market size of 150 to 200 grams by the autumn of the following year. But the biggest problem with eel farming is the source of eel fry.
Adult eels
The sex ratio of eels is not determined at birth, but is controlled by the environment and density. When the density of fish is high and there is not enough food, it will become a male fish, and vice versa. And because wild eels spawn in the deep sea, artificial breeding can not simulate the deep sea currents, food and other environments, even if the hatching of willow leaf eels, can not grow further, so that there is no good means of breeding eel fry.
Willow leaf eel
Since it is difficult to artificially breed eel fry, it is only possible to catch wild eel fry. In the face of high profits, every eel fry migration season will encounter large-scale fishing, resources will be seriously damaged, and production will become less and less. According to statistics, only 58.8 tonnes of eel fry were caught in East Asia in 2021, and this year's catch is not as large as last year.
In this case, the price of eel seedlings is becoming more and more expensive. In the face of interests, lawbreakers are desperate to take risks and catch eel fry during the fishing ban period. They use tools such as the "net of extinct households" to catch one and count one, without considering resource protection at all. In such a situation, the eels that have been breeding on the earth for tens of millions of years have really faced the risk of "extinction". In order to protect this precious fish, while continuing to combat illegal fishing, we are constantly exploring ways to artificially breed eel fry.
Artificial propagation of eel seedlings is not yet mature
For example, after decades of research, it has been found that small eels originally liked to eat "sea snow", which is a slime mass formed by the detritus of organic matter in the sea sticking together. To this end, scientists used shark eggs as the main material, combined with various vitamins, to finally feed a batch of willow leaf eels.
"Sea Snow"
However, the cost of this breeding method is too high to be produced on a large scale. Whether the fate of eels can be changed in the future requires further efforts.