Last update 3/7/2012 9:53:38 AM (GMT+7)

Scientists warn Mekong Delta may have poor shrimp crop

VietNamNet Bridge – Shrimp have been dieing in masses in many localities in the Mekong Delta, due to the seriously polluted environment. Scientists have warned that the Mekong Delta provinces may witness the failure of crop this year, while seafood processing workshops may be thirst for materials.

Shrimp dead, worries raised

Local departments for agriculture and rural development have reported that shrimp have been dying in masses right at the beginning of the shrimp crop.

Nguyen Van Khoi, Deputy Director of the Soc Trang Department for Agriculture and Rural Development, said that farmers in the province have cultured white leg shrimp on 1200 hectares of ponds, while shrimp death has been seen on 500 hectares. For black tiger shrimp culture, 30 percent of total area, or 3000 hectares has suffered.

“The damages of this year’s shrimp crop may be as serious as in 2011,” Khoi said.

In Tra Vinh province, 400 million shrimp breeders have been bred on the area of 6000 hectares. Meanwhile, shrimps have been dead in masses on 600 hectares, due to the epidemics.

The same thing is occurring in Ca Mau province. Meanwhile, epidemics have brought damages to 20 percent of the total areas. Especially, the death percentage is up to 50 percent in some localities, including Phu Tan, Dam Doi.

The Ministry of Agriculture and Rural Development (MARD) has warned that more shrimp would die in the upcoming months when the official industrial crops begin, because the water resources are getting seriously polluted with high pesticide residues.

The analysis of 8 water and 13 mud samples taken from two provinces of Soc Trang and Bac Lieu, which suffered most serious damages in 2011, showed that 100 percent of the water samples got infected with Cypermethrin residues (the concentration is 3-6 times higher than the allowed level).

Tran Quoc Viet from the Agricultural Environment Institute said that Cypermethrin is extremely toxic to crustaceans, and the concentration of 0.005 ppb would be enough to kill shrimp.

“The lowest Cypermethrin pollution level of the samples was the one taken from the river mouth, near the sea. The pollution level was higher in inner areas. This explains why local farmers say they do not use any kind of plant protection substance, but shrimp still die of diseases.

Besides Cypermethrin, the water samples have also been found as infected with other plant protection substances such as Permethrin, Chlorpyrifos and Fipronit, which were all toxic to aquatic animals. Meanwhile, the pH concentration figures in water needed for shrimp to grow in 19/21 samples were lower than the necessary levels of 7.8-8.2.

Deputy Minister of Agriculture and Rural Development Nguyen Thi Xuan Thu on also warned at a conference on February 24, 2011, in HCM City that it is high possible to see the lean shrimp crop this year due to the bad water quality.

Thu said that MARD would instruct to test the water samples in other coastal areas of Mekong Delta, following the information that shrimp ponds in Kien Giang, Ben Tre and Tra Vinh provinces have also suffered from Cypermethrin

The massive shrimp death once occurred in the first months of 2011 in Mekong Delta provinces. Shrimps died right at the beginning of the crop. Farmers tried again after 15 days, but the shrimp died again. A lot of households reportedly incurred the loss of hundreds of millions of dong because of the diseases.

Everyone understands that shrimp need a clean environment. However, local authorities still cannot do anything to help improve the living environment for aquatic animals.

Source: Dan Viet