The Phu Thanh Ltd Co has imported 504 red-swamp crawfish (procambarus clarkii) from the US to test-breed in Soc Trang Province, but has not received a licence to do so.
Tran Hoang Dung, deputy head of the Tran De District's Centre of Agriculture and Rural Development, said local farmers had informed the centre about the matter.
When asked to prove the origin of the crayfish, Phu Thanh could only present a certificate for entering Viet Nam via Tan Son Nhat International Airport in HCM City.
The company could not show a licence permitting them to import or breed red swamp crayfish.
According to company reports, 10.9kg of the crawfish was imported to Soc Trang Province on July 18. They are being bred in basins in Tran De District in Soc Trang Province.
As of last Saturday, at least 472 crawfish had died. There are now 22 males and 11 females. Those still living have been inoculated by the regional animal health centre.
Authorities are currently determining if they can be bred in a natural environment.
A representative of Tran De District's Centre of Agriculture and Rural Development said residents and the agriculture industry were concerned that the shrimp would attack and wipe out indigenous shrimp.
"This kind of crawfish has claws as big as a sea-crab. They are gluttonous and very fierce when hunting," Dung said.
"Red-swamp crawfish prefer marshes, swamps and slow-moving streams, and they reproduce similar to anabas. If they are bred in natural conditions, they will reproduce quickly and be ready to attack the native shrimp," he added.
The flesh of the crawfish is only 15 per cent of its weight, and the rest is shell.
Nguyen Van Khoi, deputy director of the Soc Trang Province's Department of Agriculture and Rural Development, said the company did not have a licence to import and test-breed this kind of freshwater crawfish.
"The company kept delaying when asked to show its import licence. On July 27, its director Ha Van Tam sent a proposal to test-breed 1,000kg of crawfish on 10ha, but again it could not present a quarantine certificate to the Department of Animal Health," Khoi said.
According to Dr Ly Thi Thanh Loan, director of the Southern Monitoring Centre For Aquaculture Environment and Epidemics under the Research Institute for Aquaculture No 2, the crawfish, if bred on a large scale in the Mekong Delta, poses a danger to irrigation works and competition for food with indigenous shrimp.
Phu Thanh Company plans to import another 1,000kg of crawfish, but the Ministry of Agriculture and Rural Development has not yet commented on the matter.
Environment activists and residents of the Mekong Delta are concerned that the crawfish could become invasive and damage other species or the environment, as did the fast-reproducing yellow edible snail, which destroyed harvests by eating leaves, the suckermouth catfish that attacked tra fish and basa fish, and the Mai Duong (mimosa pigra) tree which spread quickly over land and roads. (VNS)