Halda River, the only natural fishery in the subcontinent and home to the Bangabandhu Fisheries Heritage has become a death trap for aquatic animals.
The administration is shaken by the deaths of six fish and two dolphins within a week in June. Researchers working in Halda, including employees and officers of the Directorate of Environment and Directorate of Fisheries, are worried because of the sudden deaths of mothers and fish during the egg-laying season. Two probe bodies were formed to investigate the reasons behind the deaths of five brood fishes and one dolphin in the Halda River.
Halda Research and Laboratory of Chittagong University estimates that at least forty-three dolphins and twenty-five to thirty-five large fishes have died in the Halda River for the past five and a half years.
The primary hypothesis of the ichthyologist is that the fish died due to poisoning. Residents claimed that the fish in the Halda River were killed by poison.
“The postmortem of a dead fish is being done at Halda River Research Laboratory in Chittagong University. We can get a clear idea from this postmortem. I will be able to identify the reason for the deaths of fish and dolphins. Steps must be taken to protect Halda,” said Manjurul Kibria, chairman of the Chittagong University Zoology Department and coordinator of Halda Laboratory, Chittagong University.
"The Forest Department was given the task of protecting the dolphins in Halda. But we do not see any activity from the forest department. Even if we call them, they do not respond via telephone. Many industries were closed after the declaration of Bangabandhu Heritage. Several steps were taken by the administration. As a result, the pollution in Halda stopped for a few years, but the pollution started again recently. Halda was severely damaged. Fish and dolphins are dying," he added.
"Fish have been killed with poison. It is a grave injustice. Those who did this should be severely punished. There will be no more fish here if fish die like this every day. It will affect our livelihood,” said Moti Mia, a fisherman in the area.
The International Union for Conservation of Nature (IUCN) has listed the Gangetic dolphin as endangered. This species is protected under provision 1 of the Bangladesh Wildlife (Conservation and Security) Act of 2012.
According to experts, 1,100 endangered dolphin species are estimated in different rivers across the world. Of them, 170 were in Halda. A total of 39 dolphins died between 2017 and 2022. There are 147 dolphins on Halda, according to the 2022 census. No dolphins perished in Halda in 2022. The Halda River has seen the deaths of 41 dolphins and hundreds of dead fish of various types. However, this is the first time that six fish have died in a week.
Chittagong District Fisheries Officer Shrivas Chandra Chand made some recommendations to change this situation. “It is important to educate local fishermen and residents on the ecological significance and requirements of dolphins. Organic fertilizer use should be promoted, and excessive chemical fertilizer use on agricultural land should be avoided,” he suggested.
"All forms of illegal net fishing in the river should be outlawed. The branch canals and silt-filled regions of Halda must be cleared for sufficient water flow. It is also necessary to regularly examine the water quality in Halda and its branch canals," Shrivas Chandra Chand continued.
The fish eggs of Halda were shipped to Myanmar and other regions of India during the British-India era. Two-thirds of Bangladesh's ponds used Halda spawn in the 1960s and 1970s. Halda needs aquatic animal-friendly measures to retain its golden heritage as soon as possible.
