The Halda river is an important habitat of the endangered freshwater Ganges river dolphins. The dolphins are an integral part of the area’s ecosystem to the point that their conservation can benefit a wider range of threatened aquatic species, including turtles, gharials and fishes. But the dolphins are dying in the river at a alarming rate over the last few years. Experts say the reasons are entirely man-made, with a majority of the blame going to fishing practices in the river. Researchers recently conducted the first autopsy of one such dolphin carcass in February 2018. It was found that the cause of death was an injury caused by a sharp propeller.
The authorities recently adopted major recommendations suggested by experts that significantly reduces the numbers of deaths. A total of 18 dolphins were killed in the five months between September 2017 and February 2018. Compared to this, a total of 28 dolphins were killed in the three years between February 2018 and December 2020, while this year has seen the deaths of three more. With a lifespan of 25 years on an average, a dolphin takes nine to 10 years to mature, and it takes around two years for an adult dolphin to give birth to a calf. This means a dolphin can give birth to a maximum of five calves during its reproductive years. The rate at which dolphins are dying in the river is way faster than their reproduction rate. If proper steps are not taken in time, they could become extinct in the near future.
Conserving dolphins is important for the Halda River’s ecosystem. The Halda again is the last remaining river in Bangladesh where local carps breed naturally. We get an idea of the river’s health from the presence of dolphins. According to experts, the Ganges river dolphin was first discovered in 1801. It is an aquatic mammal found only in the Indian subcontinent. Protection and maintenance of the species will in turn help ensure better health of the rivers, which will ultimately benefit millions of members of local communities who survive on aquatic resources.
