It's the season to eat crayfish again, in the summer, in addition to barbecue, crayfish is almost a must-order dish on the table, and crayfish in our country has as many as dozens of practices, in addition to the common spicy, garlic, thirteen spices, there are egg yolk baked, chilled, salted, pepper and salt, etc., in short, there is always a cooking method to make you fall in love with crayfish, it is precisely because of this that crayfish in our country can create more than 300 billion yuan of output value in a year.
The reason why crayfish is so "hot" in our country is that in addition to its fleshy Q bomb, there is another key factor:It's almost everywhere, especially in most areas south of the Yangtze River, eitherThey can be found in rice paddies, rivers, and even ditches, and usually crayfish once they appear is "".Flooding"of.
You may not have thought of it, thoughOnce upon a time, there was not even a single crayfish in the water body of our country, so how did the crayfish go from nothing to the ditch in my country? Let's find out.
Crayfish, whose scientific name is Crayfish, is a freshwater animal under the family Decapodae, which is not a native species of China, but is native to the freshwater bodies of the southeastern United States, so crayfish is also known as "American crayfish".
We are all familiar with the crayfish, its head is large and small, the head also has a granular protrusion, the body is mainly black and dark red, the body length is usually no more than 12 cm, it originally inhabited streams and swamp areas in the United States, and likes to burrow life, however, the burrow is relatively shallow and simple.
Crayfish in its "hometown" of the United States is also a "hot commodity", in their main distribution area of Louisiana, as early as the 80s of the 20th century, crayfish with its deliciousness conquered the people of the state, elected as the state representative animal, and since then every year to hold the "lobster festival".
However, crayfish has not been "developed" in the United States, because the cooking method in the United States is relatively simple, usually mixed with potatoes and corn, and then with kajan powder (a seasoning made from garlic and a variety of spices), and this method is difficult to completely cover the fishy smell of crayfish, while in our country a random method can make people can't stop.
Although crayfish is not a native species in China, there is a freshwater lobster in China that is very similar to crayfish, it is "cricket", cricket is a specialty of Northeast China, and its scientific name is Northeast black crayfish.
However, although there is a certain similarity between the two, there is a big difference, this is because on the one hand, the yield of Northeast crayfish is relatively low, on the other hand, they are not like crayfish can adapt to any environment, but usually inhabit clean and pollution-free streams and rivers, so its own fishy smell is relatively light, and the meat is more than crayfish.
Because crayfish is not a native species of our country, and now it survives in the wild environment, it is an invasive species for our country, but from the annual consumption of crayfish in our country, its invasion is much more than other invasive species.
The reason why crayfish can enter our country is not directly introduced by the United States, but has a direct relationship with Japan. Japan was one of the first countries in Asia to introduce crayfish from the United States, around 1918, with the intention of breeding them and releasing them into bullfrog farms as food for bullfrogs.
The time when crayfish entered our country was about 1929, and there may be two reasons for entering: Japan and China's introduction, due to the lack of exact records, which reason is not determined, the reason for the introduction may have a lot to do with the crayfish as some animal feed, and there are two theories about Japan's release on the Internet: the first is to dispose of the corpse, and the second is that Japan has put the genetically modified crayfish.
However, these two statements are not very reasonable, because in 1929, the war had not yet broken out, and the genetic modification technology was born in the 70s of the 20th century, and the first genetically modified mouse appeared in the 80s, so the crayfish entered our country in 1929, and it is very likely that it was introduced by the Chinese.
In the 30s of the 20th century, when invasive species were not understood, people did not think about the possible consequences of introducing a species, and this was the case with crayfish. Since the beginning of breeding in Nanjing, people have found that crayfish has a strong tolerance, even if there is a certain amount of polluted water, it can survive, and the most important thing is that the crayfish has a strong reproductive ability, a crayfish can lay about 300 eggs a year, and these eggs can hatch after an average of about 20 days.
Strong reproductive ability coupled with adaptability, so that crayfish has become a commodity with high economic benefits, so crayfish farming began to promote, at first in the south of our country, and later people found that they can adapt to the minimum -14 environment, so the north also joined the breeding team.
Therefore, crayfish are actually from the United States to Japan and then to China, and the method of entry is most likely to be actively introduced.
In fact, in recent years, there may be less, I remember five or six years ago, I went to a friend's house in Anhui, he took me to the rice field to fish for lobsters, fishing for yellow eel, at that time there were many lobsters in it, with a piece of pork liver more than an hour to catch a small bucket, it is really enjoyable, in the ditch near the farmland, pull up the trouser leg and touch it for a while, there will be a lot of harvest.
Crayfish in China has become a ditch and rice field from the original artificial breeding, which has a lot to do with the adaptation and escape ability of crayfish.
First of all, the adaptability of crayfish we have said above, they have a strong tolerance to pollution, and they have a mixed diet, they can not only feed on plants and algae in the water, but also eat some aquatic insects, small fish and shrimp, and even carrion, they can feast on it, this adaptability, so that they can survive and reproduce well in some ditches with slow water flow and low oxygen content.
The second is escape, as crayfish become more and more popular in the country, the crayfish aquaculture industry is also expanding, and its annual output value is also increasing year by year, even in recent years, the annual output value of crayfish is growing at a rate of at least 3.
And the more breeding sites, the more conducive to the wild spread of crayfish, because crayfish migration is no problem at all, although they also use gills to breathe, but as long as the gills are moist can dissolve the oxygen in the air, and they themselves are also very tolerant to low oxygen, so that they can migrate from the breeding pond to nearby ditches, canals, ponds, rivers.
Many people say that crayfish is the most failed invasive species, if purely from the perspective of relying on breeding to meet market demand, the invasion of crayfish is indeed a failure, but in fact, crayfish have succeeded, because they already have a certain number of wild populations in China, and with breeding, there are fewer people to restrain crayfish in the wild, so to this day, they still pose a threat to native crayfish and aquatic life, therefore, it is still a "qualified invasive species".
Comments:
1. Why don't we have a river here?Coordinates: Tangshan - the road is uneven, and a roar kd
2. In the past nine years, we have found this thing in the river here in Qingdao -- Dai Tao 8i
3. None of the food made outside is delicious - riding a donkey and flying a kite.
A year ago, Hubei was not popularized, and the flood washed away some farms, which led to flooding everywhere!--Shut your mouth with a sword.