High temperature hot and thin hairy crabs?How do I hope this is a rumor

West wind sounds, crab feet itch, and it is the season to eat hairy crabs again!

However, it is hard to say if you can see hairy crabs on the table of Mid -Autumn Festival this year. A few days ago, "Yangcheng Lake hairy crabs are absent from the Mid -Autumn Festival" to the hot search. This is not only because the Mid -Autumn Festival this year is relatively advanced. The crabs are not ready, but because the weather is too hot, the crabs are not meaty.

Can we still eat delicious hairy crabs this year? Is it really hungry and thin hairy crabs?

Why is there no meat in hairy crabs

Crab will be thin, it is true!

The most suitable water temperature for crabs is 18 ° C to 25 ° C. By 30 ° C, their appetite will gradually decrease, their physique will decrease, and they will be prone to illness. Under the hot sun this summer, the temperature of the water surface in some areas may reach 40 ° C. Crabs do not think of tea, and naturally cannot increase weight. In addition, crabs are omnivorous animals. The feed often has small miscellaneous fish. During the high temperature, the crab appetite is not good. If you do not eat small fish in time, it will easily become corrupted and deteriorate, which will cause the water quality to deteriorate, which will affect the growth and development of crabs.

The growth of crabs requires 5 molten shells to become crab, which can double after each molting. The fourth molten shell of crabs usually occur in July, and their weight can reach more than 2 or more after the molten shell. However, the time tortured by high temperatures will be delayed by 20 to 30 days this year. There are only less than 1.5 crabs that have not completed the fourth molten shell.

Crab that is working hard to molt the shell

There are many crabs died before the successful molting. Some crabs were forced to run on the shore by high temperatures, and eventually they died of dehydration; there were some crabs died of illness -high temperature caused water plants to rot, the oxygen content in the water decreased, ammonia nitrogen harmful substances increased, bacteria reproduced a large amount, and eventually the immunity decreased. Crabs will be stained with diseases, such as crustal ulcers.

Although the autumn wind has risen, the temperature is not as high as before. The large -scale listing of hairy crabs this year still needs to wait until October. The hairy crabs at the Mid -Autumn Festival energy -saving table are not as strong as in previous years. Everyone has to prepare for psychological preparations. This year's hairy crabs are likely to be smaller than in previous years, and because of the high mortality rate, the total output of hairy crabs will decrease by about 20%. Hairy crabs are inevitable that the price will inevitably rise.

Other seafood is also very hot

High temperatures not only make us torture, but also make hairy crabs thinner, but also affects farming fish and shrimp and shellfish in the coastal areas.

The suitable temperature of the sea bass life is 20 ° C to 28 ° C, and the water temperature in the high temperature of the sea bass farming area in Guangdong can reach 35 ° C. , Easy to get sick. With low temperature and low pressure, the dissolved oxygen content in the water drops rapidly, especially the middle and lower water bodies of sea bass life. Farmers need to be an oxygen in the fish pond to reduce their death.

The problems brought by high temperatures are too high in seawater salinity. When the water body evaporates quickly, the salinity of the water will rise quickly, and once it exceeds the tolerance range of fish and shrimp, it will cause losses. For example, the seawater salinity adapted to the South White Placs is 10 ‰ to 20 ‰, but in the white -pairing shrimp production area of ​​Taizhou this year, the salinity of the water body reached 32 ‰, the immunity of white -to -shrimp decreased, and the pyramid was spread faster. Fortunately, the pathogens of white shrimp will not be transmitted to the fish. The shrimp was finally salvaged and poured into the nearby fish breeding area, becoming a meal for big yellow croakers (shrimp:?).

Can't waste! The end of the South White Plack Shrimp turned out to be like this ... | Skretting.com

High temperature will also cause sea water shellfish to die in large -scale in summer. For example, at a temperature of about 30 ° C, a large number of oyster herpes virus (OSHV-1) spread a large number of oysters to die. The appropriate seawater temperature range of abalone we often eat is 10 ° C to 22 ° C. When the water temperature exceeds 28 ° C, they cannot live normally. In Fujian in their main producing areas, due to the continued high temperature and unstable dissolving oxygen in the summer, the mortality rate of wrinkles disco is as high as 25%to 60%, causing huge losses every year.

Cooked mussels on the beach of Vancouver | Alyssa Gehman

Such things happen not only in our country.

Last year, under the extreme high temperature in summer, tens of thousands of mussels, clams, starfish and rattan pots on Vancouver, Canada were lived alive, and even split the meat inside. The taste is like a huge "open -air barbecue". Scientists estimate that 1 billion shellfish creatures have died in this high temperature. The ability of shellfish filtering is very strong, and it is very important in the ecosystem. Their death will trigger a chain reaction, allowing more creatures to face the disaster.

Strive for summer heat

In order to make the fat hairy crabs smoothly on the dining table, crab farmers also adjust the breeding method based on their living habits.

A comfortable aquatic environment can reduce the impact of high temperature. As the temperature rises, the crab farmers will gradually increase the water level of the crab pond, and add water and change water in time. Under extreme high temperatures, they even have to add ice to the water. In order to avoid hypoxia, oxygen -aged machines are also set in the crab pond to increase the amount of soluble oxygen in the water.

The aquatic plants in the crab pond are also very useful. Water plants can help purify the water quality, and can also provide crabs with a place for cooling. They are rotten and make crabs have sufficient living space. As the saying goes, "crab size, look at waterweed", water plants in the crab pond are essential to the health of crabs

In addition to the environment, food is also very important. Crab feed must pay attention to the combination of vegetables. At the high temperature stage, crab farmers will slightly reduce the proportion of food, add more green feed, and also feed a small amount to avoid animal feed rotten and deteriorate water. When the temperature is reduced, when the fattening is yellow, they will increase the food to the crabs and increase their weight. In addition to these staple foods, crab farmers will also add minerals and vitamins to the water. Some crab farmers will also add garlic and sugar to the feed (the seasoning is added), hoping to help them shed smoothly.

However, these methods can only reduce the impact of high temperature on crab output to a certain extent. The temperature rises for many years, not just hairy crabs and other aquatic products, many delicious people are in danger. From kiwi, citrus to coffee beans, even the production of peppers will be greatly reduced at high temperature -protecting the environment and slowing climate changes is that we are facing facing The biggest challenge.

references

[1] Unveiled books should be. Yangcheng Lake hairy crabs may be absent from the Mid-Autumn Festival table [n]. First Financial Daily, 2022-09-05 (A10).

[2] Ding Weiwen. How to save the current "crab disaster"? Is the price of crabs expensive after autumn? How to raise crabs in the future? [N]. Xinhua Daily, 2022-09-05 (008).

[3] Wu Zhengbing. Management during the high temperature period of crab breeding [J]. Farmer staff, 2018 (23): 117.

[4] Lin Peng. Common problems and management points of crab breeding in high temperature season [J]. Modern Animal Husbandry Technology, 2016 (10): 44.DOI: 10.19369/J.CNKI.2095-9737.2016.033.

[5] Wu Qiong. Discovery of Danshui Crab Breeding Technology [J]. Heilongjiang Aquatic Products, 2018 (05): 24-26.

[6] Wang Shanwu, Wang Xiao. Talk about the analysis of the technical analysis of freshwater crab breeding [J]. Modern agricultural research, 2020,26 (10): 89-90.doi: 10.19704/j.cnki.xdnyyj.2020.10.041.

[7] Zhou Xiaowei, Lu Changmei. Talking about the method of crab breeding and water quality management [J]. China Agricultural Information, 2014 (01): 149.

[8] m.cnhubei.com/content/2022-08/08/content_14964663.html

[9] Hu Geng, Liu Debin, Wang Jiawei. The current status and high temperature breeding management measures in abalone breeding in my country [J]. China Aquatic Products, 2015 (05): 76-77.

[10] Lin Siheng. Wrinkle Plate Bao Du Xia's death and high temperature coercion response Study [D]. The Graduate School of the Chinese Academy of Sciences (Institute of Ocean), 2016.

[11] https://www.washingtonpost.com/world/2021/07/08/canada--creatures-boiling--deth//

[12] www.davidpublisher.com/index.php/home/article/index?id=25946.html

Author: Cat

Edit: Turn over

- END -