The truth about the nutritional value of the 'monster' crayfish

According to experts, crayfish are not as nutritious and delicious as advertised by sellers. Crayfish are an alien species that destroys the native ecosystem and are therefore banned from being traded and bred.

Crayfish "invades" online market

In recent days, many people have been selling live crayfish in large quantities on online seafood markets. This type of lobster is as small as whiteleg shrimp in our country, and has very little meat. However, when cooked, they are advertised by traders as having an extremely attractive red color, firm and sweet meat. Customers can buy them to make lobster with garlic butter sauce, tamarind sauce, or spicy stir-fry.

Currently, the common price advertised by dealers is from 360,000-400,000 VND/kg. Compared to the same period last year, the price of crayfish has decreased by about 30-40%, but is still more expensive than Vietnamese whiteleg shrimp sold in the market. May-July is the season of crayfish in China. This year, the supply is abundant, goods are pouring into the market in large quantities, so the selling price has also decreased sharply compared to previous years.

Crayfish are not very nutritious and have very little meat.

Ms. Le Thu Thao, a crayfish seller on Facebook, shared that this type of crayfish is very healthy and is bought by many customers, so importers like her really like it. Crayfish can live healthily all day without water. If you import a large quantity, you just need to put it in a water tank and it will stay healthy all week, there is no phenomenon of weak or dead shrimp, so the loss rate is very low.

Ms. Thao shared that shrimps are arriving in large quantities this time, and customers who order will receive delivery on the same day. The public selling price is only 370,000 VND/kg, a sharp decrease compared to the same period last year. "The crayfish arriving at the market are 35 pieces/kg, very healthy. This type of shrimp is packed in mesh bags weighing 1 kg/bag and then transported to the market," she said. Every day, she imports shrimps from large suppliers depending on the number of customers ordering. Some days it is only 30-40 kg, other days it is up to 100 kg.

Mr. Nguyen Van Long, Director of the Department of Animal Health (Ministry of Agriculture and Rural Development) said that crayfish (also known as freshwater crayfish) has the scientific name Procambarus clarki. This type of crayfish is listed in Appendix 2 of Invasive Alien Species issued with the circular of the Minister of Natural Resources and Environment issued in 2018.

Live crayfish are also not listed in Appendix VIII of the List of aquatic species permitted for trade in Vietnam - issued together with Decree No. 26/2019 of the Government detailing a number of articles and measures to implement the Law on Fisheries.

According to aquatic experts, crayfish can become a disaster for the agricultural industry. Because of their habit of living on the bottom, like to dig holes, like the dark, and are active at night. They can dig holes 100-200cm deep, live both underwater and on land and withstand temperatures of 0-37 degrees Celsius. The main food of this type of shrimp is organic debris, cereals, dried beans, vegetables, young grass, water grass, algae, insects, small benthic organisms, animal carcasses, processed food.

Crayfish is mainly shell, the meat is not as delicious as advertised.

Dr. Nguyen Quang Huy, Research Institute for Aquaculture I, said that Vietnam imported crayfish from China and tested them in Phu Tho, Ninh Binh and Ha Nam provinces in 2006. The results showed that this species lives hidden in the roots of trees along rivers and lakes, even crawls up to land to breathe oxygen, often digs burrows 1-2 meters deep, so they can destroy agricultural irrigation systems. They are also hosts that transmit and spread many types of diseases into the environment, compete for food, and destroy native shrimp and fish species.

 Crayfish are hosts that transmit and spread many types of diseases into the environment where they live.

Dr. Nguyen Quang Huy said that introducing this species to Vietnam for farming may bring some immediate benefits, but the damage it causes to agriculture is terrible and long-lasting. They crawl quickly, spread widely, and are harder to destroy than golden apple snails. If red-claw crayfish are not banned but allowed to be farmed, biodiversity, ecological environment, aquaculture, and rice production are at high risk of suffering huge losses, with long-term consequences.

According to experts, crayfish are hosts that transmit and spread many types of diseases into the environment where they live and reside. Many countries prohibit crayfish farming, some countries allow farming in certain areas but strictly control it. In countries that allow farming, most of them have unfavorable natural conditions, they are forced to allow farming of this shrimp breed for economic benefits but with strict control measures.

Regarding the information that crayfish is a species that produces meat more delicious than tiger prawns, Dr. Nguyen Quang Huy said that red-claw crayfish only has 30% meat and 70% shell , the meat and nutritional content is not higher or more delicious than tiger prawns and white-leg shrimps currently available in Vietnam. Crayfish do not have high economic value.

Their meat is very little, a kilo costs about 400,000 VND but only has 300 grams of meat, the rest is just shell. Compared to native shrimp species such as tiger prawns, whiteleg shrimp, and green-legged shrimp, they are not as delicious. Many people eat red-legged shrimp because it tastes strange, and over time they get bored. "We have many better shrimp varieties to choose from, so why should we allow red-legged shrimp farming with so many potential disasters?" , experts asked.

According to Dr. Nguyen Quang Huy, if these species are not banned but allowed to be raised, then biodiversity, ecological environment, aquaculture and rice production industries are at high risk of suffering huge losses, with long-term consequences.

No one is allowed to buy or sell it for food, no matter how delicious or cheap it is, we absolutely must not use it because of the importance of protecting native biodiversity , the sustainability of agricultural ecology and the food safety of a country that grows rice on a large and fragmented scale like ours .

At one point, the Ministry of Agriculture and Rural Development had to issue an urgent dispatch requesting provinces, cities and authorities to intervene to prevent and hunt down crayfish. If discovered, they must be destroyed immediately and trading activities must be strictly punished to avoid spreading this alien species into the environment.