VietNamNet Bridge – Sucker-mouth fish, an invasive species of South American origin, have appeared in large quantities in the Cuu Long (Mekong) Delta, threatening the lives of indigenous aquatic species.

In Kien Giang Province, the fish, which was first imported into Viet Nam as an ornamental species, has appeared in many rivers, canals and ponds.

Many farmers said that 10 per cent of the total amount of fish harvested from their ponds was sucker-mouth fish.

In recent years, sucker-mouth fish have reproduced rapidly and competed for food with other indigenous species, said farmers.

The fish have also dug holes in river banks and rivers, causing land erosion, they said.

Sucker-mouth fish have been released into the natural environment by people who raise ornamental fish, according to farmers.

The Kien Giang Department of Agriculture and Rural Development has petitioned the Directorate of Fisheries to support measures to control the fish and restrict the damage of this invasive species.

In Bac Lieu Province, sucker-mouth fish have reproduced in large quantities in canals and fish ponds.

Ma Hoang Vu from Vinh Loi District's Long Thanh Commune said last year he put 20kg of several kinds of small fish, including tilapia, carp and snakehead fish, to raise in his house's nearby pond.

Vu said he had harvested only 3kg of tilapia and snakehead fish, but about 50kg of sucker-mouth fish of various sizes.

Sucker-mouth fish have no economic value, and after caught, people often return it to the environment, leaving the fish to develop rapidly, according to the Bac Lieu Sub-department of Aquatic Resource Exploitation and Protection.

In a pond, sucker-mouth fish eat algae, seaweed, other food and eggs of indigenous fish species and reproduce rapidly.

To control the fish, experts have advised farmers to use the fish as animal feed.

Source: VNS