1. The glory of Da's loach
Distributed in the Heilongjiang River, the boundary river between China and Russia, the Dashi fish is a typical freshwater fish species that swims in the river channel all year round, not close to the shallow sea. Dashi loach, fierce in temperament and huge in size, firmly occupies the top position of Heilongjiang's food chain, and is known as the "king of fresh water".
Worryingly, today's population has shrunk so much that it is listed on the IUCN Red List of Threatened Species and rated "critically endangered". In 2019, it was included in the "Directory of Aquatic Wild Animals under National Key Protection for Artificial Breeding" compiled by China's agricultural department, which reflects that the situation of Da's loach is not optimistic.
Compared with the current dismal situation of the Dashi loach, the historical Dashi loach has also been brilliant for a while. The earliest record of Dashi's fish in China can be traced back to the "Book of Poetry Zhou Songqian" written in the pre-Qin period, which wrote that "there are fish and there are fish", and the fish here refers to the Dashi fish.
The later "Mao Shi Grass, Wood, Birds, Animals, Insects, And Fish Thins" further pointed out the wonderful edible value of Dashi's fish, describing it as "steamable and steamed, but also can be fish, and the seed can be sauce". This means that the meat of Dashi's fish can be boiled with the soup and delicious taste, or the fish and rice can be combined, layered in the altar, sealed and marinated, and stored for a long time.
The last caviar can be made into caviar, and today's caviar is sought after by consumers, which has reached the point of no return, and it has joined the ranks of the world's top cuisine, and it is internationally praised as "black gold".
Although the Dashi loach has long been famous in history, but the length of 4-6 meters, the weight of 400-1000 kg of behemoths, ancient fishing nets, boats to catch them is not an easy task, so in the past two thousand years, the number of Dashi loach is extremely stable, carefree swimming in the Heilongjiang River.
The turning point occurred during the Kangxi period of the Qing Dynasty. After the Manchus entered the customs, they continued the yuan dynasty's annual tribute to the Dashi clan. The thornless, white and crisp flesh quickly conquered the taste buds of the court nobles. The Kangxi Emperor praised the Dashi loach and gave it the name "鳇", which is the origin of the name of the Dashi loach.
More than 100 Qing Palace scientific and technological relics in Jinan exhibited Western science and technology in the eyes of the emperor
In order to facilitate the court people to taste the Dashi loach at all times, the Qing Dynasty set up a special department of "fighting the animals and ulla in charge of the Yamen", and the guards were also responsible for fishing the Dashi loach, which was continuously transported to the court throughout the year. Two hundred years of fishing, limited by the backwardness of fishing tools, the population of Da's loach will not be greatly reduced, causing a fundamental impact, but undoubtedly conveys a signal to the outside world, that is, Da's loach is a valuable high-end ingredient, worth eating.
On June 17, experts from the Aquatic Animal Resources Conservation Center of Heilongjiang Province administered medicine to Dashi fish
2. The cause of the endangerment of the Dashi scorpion
The real path to extinction is something that has happened in recent times, and the factors are extremely complex.
The delicious taste and economic value of dakhles are one of the important reasons for the overfishing and decline in population. As mentioned above, in ancient China, there was a tradition of making caviar from Dashi's fish roe, and in the early twentieth century, many countries blew up a boom in eating caviar, and finally even evolved into a high-end social etiquette.
The strong reproductive ability of the Dashi loach was originally the need to adapt to the environment and continue the breeding of the race, but it became the fuse for being rounded up in large numbers. The dalleins mature later, and the females generally wait until the age of 16-20 for the gonads to mature. However, females lay large amounts of eggs, laying between 200,000 and 4 million eggs at a time. Someone once calculated that if these fish eggs were separated one by one, it would be a distance of 130 kilometers. After the eggs are fertilized, it takes only 5 days to hatch the juveniles at a water temperature of 15-18 ° C.
2020.6.20 4.30pm A giant injured squid with a body length of 2 meters and 9 and a weight of about 300 pounds
The price of caviar for darlings in the market remains high, and the price of fresh fish eggs is also rising, with the price of each catty exceeding $300, and it is not too much to describe them as "black gold". The final result is that every spring, when the Dashi fish was breeding, a large number of purse seines and boats were gathered, and dozens, if not hundreds, of modern fishing boats were distributed in the Heilongjiang River. A large number of female burrows with bulging abdomen are caught, followed by caesarean section, and then either immediately produce caviar or refrigerate the roe.
In fact, Russia's fishing for darling should not be underestimated. The opening paragraph mentions that the Dashi is distributed in Heilongjiang, while a considerable part of it is distributed in the middle and lower reaches of the Heilongjiang River, especially near the mouth of the sea, although the Dashi is not exposed to seawater. In 2004, China and Russia formally signed a border agreement, from the confluence point of the north-south source of the Heilongjiang River to the confluence of the Heilongjiang and Ussuri rivers in Khabarovsk, Russia, as the border river between the two countries, since then all the following parts are owned by Russia, including the estuary that finally flows into the Strait of Okhotsk.
Since the end of the Qing Dynasty, after controlling the middle and lower reaches of the Heilongjiang River through unequal treaties signed, Russia has begun to fish wildly for Dashi fish, and a large number of fish eggs have been processed into caviar and introduced to the market for huge profits. What's worse is that Russia has built a large number of hydropower stations and dams in the areas under his control, such as the Jieya River water conservancy hub and the Breya River hydropower station, which undoubtedly hindered the upstream of the Dashi fish. In the long run, it is obvious that it has an adverse impact on the mating and reproduction of species of Dashi.
Heilongjiang source scenery 001
On the other hand, deteriorating water quality and reduced catches are also responsible for the decline in the population of Daspert's fish. Heilongjiang and China's Yangtze River, Yellow River, Pearl River similar, 80 years after a large number of modern chemical plants, smelters, paper mills up, in view of the current situation at that time, many wastewater, sewage, irrigation water almost did not do purification treatment, directly discharged into the water. As water quality deteriorates or populations decrease, so does the survival rate of fish eggs.
Dasper's is a typical predatory fish, feeding on benthic small fish and shrimp, including another rare fish in China, the salmon. Dashi loach swallows dozens of fish at a time, at least dozens of pounds, like 5-10 pounds of salmon, swallowing a piece of cake. The reality is that the catch in Heilongjiang has been greatly reduced, so it is more difficult for Dashi to forage, and occasionally there is a lack of food, which naturally affects their normal reproduction.
It is the combination of these factors that reduces the number of tarragons. In 2016, the Fishery Resources Department conducted a survey on the current situation of Dashi in the Heilongjiang section of China, and the results showed that the number of Dashi's loaches accounted for only 0.15% of the catch, and it was on the verge of extinction.
The Fish Skin Tribe of the Hezhe people of China
3. The current situation and protection measures of Dashi slug
In order to increase the population of Dashi loach, in fact, China began the artificial breeding of Dashi in 1997 at the Heilongjiang Fishery Fish Research Institute, and hatched the dashi seedlings for the first time under artificial intervention in 1999, with a total of 490,000 seedlings released to Heilongjiang.
It should be noted that the Da's fish is not a protected animal in China, but there are cases of fishermen's bycatch. Sometimes higher profits attract, and instead of choosing to release, they sell directly.
In 2014, at the confluence of the Heilongjiang and Songhua rivers, fishermen accidentally caught a 2.5-meter-long and 260-kilogram Dashi loach while carrying out a fishing operation. Fortunately, it was finally bought by an enthusiastic mass of more than 60,000 people and put back in Heilongjiang.
Heilongjiang Fish Exhibition Hall in Fuyuan County, Jiamusi, Heilongjiang
In June 2020, fishermen in Changfa Village, Xingfu Township, Aihui District, Heilongjiang Province, caught a 2.9-meter, 300-pound female Dashi who had been growing for 30 years. Unexpectedly, this female Dashi was already "pregnant with Liujia". The Heilongjiang Fisheries Research Institute immediately sent two experts to "take care" of the to-be-produced Dashi. After more than a month of cultivation, with the help of artificial induction, 90,000 seedlings were successfully hatched and released to Heilongjiang.
It is true that the above practice deserves recognition and praise, but it is undoubtedly a drop in the bucket for the entire population of Dachshund. In addition, in order to accelerate the reproduction of Dashi sturgeon, some experts choose to cross Dashi sturgeon and Shi's sturgeon, which can indeed achieve higher economic benefits overall, but from the perspective of a long span, the genes of Dashi's sturgeon are destroyed, and if they are not careful, they will spread to the entire community, but choose a chronic method of death.
In fact, like salmon, strengthening the protection of Heilongjiang and restoring the ecology is fundamental. At the same time, it is a long-term solution to negotiate unified protection measures with Mongolia in the upper reaches of the Heilongjiang River and Russia in the lower reaches.
Original: Old High