Invasive sucker fish threatens native fish in Shitalakshya

KALIGANJ, GAZIPUR, July 24: An invasive species of suckermouth catfish is rapidly spreading in the Shitalakshya River in Kaliganj, replacing native fish in fishermen's nets and raising concerns over the river's declining biodiversity.

Local fishermen say they are catching increasing numbers of the armoured fish�"commonly known as the suckermouth catfish or "sucker fish"�"instead of native species such as rohu, catla and tengra.

The fish, which has a hard, spiny body, is often caught in large numbers. Its sharp fins have also injured fishermen while handling their nets. Although some try to sell the fish along the riverbank, there are few buyers.

Liton Mia, who fishes regularly in the Shitalakshya, blamed industrial pollution for the decline of native fish population.

"The river water has been polluted by industrial waste. Fish are no longer as abundant as they once were. For the past week, I have been catching between 5kg and 20kg of suckermouth catfish every day, but nobody wants to buy them," he said.

Saifur Rahman, a resident of Bhadartti Dakshinpara Village, said the fish feeds on small native fish and their eggs, posing a serious threat to the river's ecosystem.

"This is truly a destructive fish. Fishermen should be encouraged to catch more of them," he said.

Another resident, Al Amin Sarkar Sumon, said the species had become a growing menace.

"The fish looks frightening, and its impact is even worse. Small native fish have almost disappeared from the Shitalakshya," he said.

Monir Hossain echoed the concern, saying pollution had already reduced fish stocks in the river, while the invasive species was further accelerating the decline.

"If immediate action is not taken, native fish in the Shitalakshya may one day exist only in stories," he said.
Kaliganj Upazila Fisheries Officer Abu Sama said the suckermouth catfish is an invasive foreign species that is not considered suitable for consumption.

"It feeds on aquatic organisms, fish eggs and food sources of native fish, causing severe damage to aquatic biodiversity," he said.

Although the Fisheries Department has taken various initiatives to control the species, it has not yet been able to contain its spread effectively, he added.

Local residents and fishermen urged the authorities to take effective measures to control the invasive fish, reduce river pollution and protect the Shitalakshya's native fish species before the ecological damage becomes irreversible.