More than 100 river dolphins were found dead in the Sundarbans, the world's largest mangrove forest, in the last 12 years.
According to these statistics, on an average nine dolphins are killed every year.
Wildlife Conservation Society Bangladesh (WCS Bangladesh) reports that one third of the dolphins are killed as they get tangled in the net and die of asphyxiation.
On Jul 31, a river dolphin — locally known as shushuk, which weighed more than 120kgs and was eight feet long, was found dead in Durgapur upazila in Rampal, Bagerhat after it got tangled in a fishing net.
The report also confirmed that from 2007 to 2019, a total of 108 dolphins died. Of these, 80 were shushuk, 24 were Irrawaddy dolphins and four were wingless porpoise dolphins. Some died after getting tangled in the current net that is normally used to catch ilish fish, while others died by being hit by boats.
Madinul Ahsan, the divisional forest officer of Wildlife Management and Nature Conservation Division, has said that 14 dolphins and shushuk have been killed in the Sundarbans, over the last six years.
He said a shushuk was found floating dead on Mongla River on Jul 31. The dead dolphin had its teeth tangled in the fishing net. An autopsy was conducted to find out the cause of death.
According to the Wildlife Conservation Act, 2002, killing dolphins that lives in rivers is a punishable offense.
It is reported that shushuk and irrawaddy dolphin (Orcaella brevirostris) dolphin often get trapped in fishing nets in the Sundarbans region and adjoining rivers.
The dolphins can sometimes be seen floating around the rivers or seas to breathe, and getting trapped in the net creates issues as they cannot breathe while entangled in the fishermen's nets.
Most of the time, it is seen that teeth of the shushuk and fins of irrawaddy dolphins get tangled in the net, which in turn kills the dolphins.
Current conditions of dolphins
“Identifying Dolphin Hotspots in South Eastern Bangladesh,” a report titled by WCS Bangladesh, said 225 shushuk are found in less saline water in Sundarbans.
According to the survey conducted in January 2018, there are 159 shushuks.
In another survey conducted in 2006, there were 451 Irrawaddy dolphins but the number decreased to 198 when the survey was again conducted from January to April 2019.
Nadim Parvez, WCS Bangladesh's Education and Livelihood Coordinator, said that killing, hunting, eating, or selling dolphins of any species is a criminal offence.
“Dolphins help keep rivers and seas healthy. Moreover, reducing the number of dolphins means there is a decrease in the amount of fish; their disappearance will have a negative impact on our lives. Therefore, protecting these dolphins is everyone's duty,” he said.
He added: “Untangling a shushuk or dolphin from a fisherman’s net is an easy task. WCS, local fishermen, and the Citizen Science Fisherman Safety Network are now working together to protect dolphins and turtles once they get trapped in the fishing net.”
Furthermore, WCS is collecting information about dolphins dying in the Sundarbans and surrounding areas through the help of the Dolphin Mortality Monitoring Network, Nadim said. Through the help of the findings and contributions from the WCS study, the government of Bangladesh created three sanctuaries for dolphins in the Sundarbans.
“WCS believes that through the collaboration and joint effort of the government, fisheries and locals, the Sundarbans can be safe for dolphins,” he expressed hope.