Fish that had been eaten for thousands of years were suddenly endangered, and no one knew where they came from

2022-05-01 0 By

When you hear the word “eel,” people probably think of a traditional Japanese rice dish called rice with eel.Eel rice as an island country that depends on the sea to eat the sea, Japan has a lot of fish cuisine. Eel rice has been inherited from the Edo Period more than 400 years ago, and has become known to the world with the circulation of its literary works around the world.Motota Kojima, a member of the supporting teenage detective team, is a fan of eel rice in his famous long-running mystery manga series Detective Conan, which was serialized from the end of the 20th century to today.But eels are not exclusively Japanese.Eel is rich in high-quality protein and all kinds of amino acids and vitamins required by the human body, as well as deep-sea fish oil components known as “brain gold”, the content is higher than many other fish, it becomes a good food on the table without doubt.In fact, human consumption of eels dates back to prehistoric times, and it is this fish, which has been eaten for thousands of years, that has become endangered in recent years.Eels Biologically speaking, all fish belonging to the order anguilla are what we call eels in daily life, long snake-like fish.There are 18 species of eel in the world, mainly distributed in tropical and temperate regions, preferring clean, pollution-free waters. The eels we are talking about today are mainly Japanese eel, American eel and European eel.Japanese eel, also known as wind eel, white eel, green eel, mainly distributed in Vietnam, the Philippines, China, the Korean Peninsula and the Japanese islands, tail with black ring, slender snout tip, black green body gray belly.After a certain period of growth in fresh water, Japanese eels return to the sea to lay eggs. After hatching, the larvae take three months or even half a year to return to fresh water.In 2017, Japanese eel fishing, which had been listed as endangered by the International Union for Conservation of Nature, suffered a shortage of fish, with the total catch less than 1% of the same period last year.American eel, also listed as an endangered species along with the Japanese eel, is found along the Atlantic coast from southwest Greenland to Central America, mainly in the United States and Canada.In terms of price, The Japanese eel is the most expensive and the American eel is the second most expensive. The oil of the Japanese eel is distributed in the meat, and the American eel is concentrated in the liver, so the American eel tastes more like lean meat.Female American eels lay their eggs in salt water and take nine to ten weeks to hatch. Many of these eggs die after being laid, and the successful juveniles travel to North America until they enter freshwater systems.European eels are native to the Atlantic Ocean and are found in the Mediterranean Sea, the Baltic Sea, North Africa, Morocco, Scandinavia and other waters.They cross the Atlantic ocean to spawn in the Sargasso Sea during breeding season, and the hatchlings follow ocean currents to the coasts of Western Europe, where they enter rivers to live.As adults, they swim back to the Sargasso Sea to spawn.The European eel is already listed as critically endangered by the International Union for Conservation of Nature (IUCN) because the Spanish, who feast on eel larvae, have seen their numbers decline by 90 percent in just a few decades.If you type in “eel” in a browser, you’re most likely to find popular or home-cooked eel recipes — studies of eel recipes — but are eels really being eaten to the point of extinction?Eels are endangered, apparently because of how they breed.Eel food consumption as a great ingredient of eel appear in different countries of different nationalities on the dining table, cooking methods are various, eel is still can’t really for artificial breeding, however, the natural growth of eel can’t cover the output of human need, and eel breeding approach means that they will encounter a lot of loss in the process of natural growth.Eels have very special living habits. They grow into adults in fresh water rivers on land, and migrate to the ocean to lay eggs after maturity. This process can be as short as a few months or as long as a few years.A small number of fish eggs hatch successfully in the ocean, and few of them make it back to freshwater systems as they migrate across large areas of the ocean.This migration process is thousands of nautical miles long, which cannot be simulated in artificial environment. Therefore, no matter how advanced the farming technology is, and how high the economic value of eel is, the artificial breeding technology of eel still remains stagnant. This is even known as the Goldebach conjecture of biology.In the 1930s and 1940s, there were studies in France on artificial maturation of European eels, and there were large-scale artificial breeding efforts in Japan, but eels die soon after they hatch.The farmed eels you can eat today were actually wild fry pulled from the sea long ago and raised by farmers.Exactly where and why wild eels originally came from remains a mystery.Domestic eel farming began around 1980, and artificial breeding of eels is still in the laboratory stage.The life of the Eel It wasn’t until the early 20th century that the life of the eel was clearly understood.Eels have six developmental stages from egg to adult. Eels at different stages look like different fish and have different names.In the first stage, the eggs of adult eels migrate to fixed spawning sites to lay their eggs, with Japanese eels in the Mariana Trench, the world’s deepest trench, and European and American eels in the Sargasso Sea.When a newborn eel swims long distances in the ocean with the current, it swims offshore. Its flat, transparent body is as thin as a willow leaf, making it easy to drift with the current.It can take up to six months for an eel to grow from a willow eel to a glass eel when its body is streamlined near shore, reducing drag and allowing it to escape the current.In 2017, an online video went viral, calling glass eels “the most privatefish in the world.”When coastal fishermen have fishing season, will be put out to sea fishing, and have not been fishing into the estuary water area, such as glass eel will start fresh life, glass eel body began to appear melanin, originally be eel line, also called sunspots or black son eel, the period at the mouth of the glass eel or in the sea fishing catch eel line is the source of the eel breeding eel seedling.Eels that grow in fresh water gradually turn yellow from their belly to yellow eels over a period of seven to 50 years.Eels do not return to the depths to spawn until they are mature and turn a silvery white color similar to that of deep-sea fish, known as silver eels. That is, when they become silver eels, the eels begin to differentiate between the sexes.It depends on the environment, with the proportion of females increasing when the shoal is small, and the opposite when the shoal is large.At this time, eels’ eyes widen and their pectoral fins widen in preparation for their upcoming journey through the ocean.There is a market for endangered eels, which are naturally overfished. According to the Food and Agriculture Organization of the United Nations, about 130,000 tons of eels are consumed worldwide each year, about 70 percent of which come from Japan.In Japan, the consumption of river eels reached 120,000 tons, which might not have seemed like much if the Japanese glass eels had caught 140 tons in 1965, but by 2000, they had caught less than 40 tons.By 2013 it had dwindled to just 5 tonnes, and in December 2017 only 184 grams were caught.Eels, which rely on wild fry to breed, depend on the supply of nature, so they remain a wild resource.In 2014, China, Japan and South Korea agreed to limit future catches of eel seedlings to 80% of that year’s total, but the limit was set so high that it would almost have reached the red line if all eel seedlings had been harvested that year.Under these circumstances, various countries are taking measures. In addition to studying the technology of artificial breeding of eels, they are trying to find ways to limit fishing and trade restrictions. In China, fishing eel larvae requires a license to carry out.Each eels into the depths of the sea in the process of almost won’t eat, and died in the spawning grounds, they took to is a slippery slope, and the natural ecological environment in the survival of human activities have been too many changes, every new an endangered species is a reminder again, hope that mankind will find better ways of harmonious coexistence with nature, not to have on the future of no return.