MANDALAY — Researchers say the depletion of fish stocks in Burma’s largest river is threatening a vital source of food for the Irrawaddy dolphin, an endangered species whose population is estimated to number less than 100.
Environmental degradation along the Irrawaddy River is to blame for declining fisheries, as are fishermen who use electrical shockers to boost their catches, affecting the river’s small Irrawaddy dolphin population in ways both direct and indirect.
“Fishermen nowadays use high-voltage electrical shockers to get more fish, and this is how some dolphins get directly shocked and die. For some, they are only slightly shocked, but later die [as a result],” said Kyaw Hla Thein from the Wildlife Conservation Society’s Burma program, who is involved in Irrawaddy dolphin conservation efforts on the river.
According to the New York-based Wildlife Conservation Society (WCS), which is working jointly with Burma’s Department of Livestock, Fisheries and Rural Development for the preservation of Irrawaddy dolphins, the population of a designated protection zone in the upper region of the Irrawaddy River is in decline.
In early 2012, WCS said the total population stood at around 86 dolphins, but by January of this year it had fallen to an estimated 63.
The area, between the riverside towns of Kyauk Myaung and Mingun in Sagaing Division, spans about 230 miles (370 km) of freshwater in which Irrawaddy dolphins can be found, and was established as a protection zone in 2005.
Measures to protect Irrawaddy dolphins include the prohibition of mercury use in gold mining operations, and a ban on catching or killing of the dolphins, or trading in their meat. Electro-fishing is also forbidden, as is the use of gillnets more than 300 feet (91 meters) long, or spaced less than 600 feet (180 meters) apart. The release of dolphins entangled in fishing nets is mandatory.
Despite these efforts, environmental destruction, deforestation and a growing number of mining operations continue to negatively impact on the river’s ecosystem. Mercury contamination from gold mining is said to be a leading cause of the waterway’s declining fish stocks.
“In 2012, fishermen using normal methods caught more than 25 kilograms of fish, which provided enough for a day’s earnings. But nowadays they can catch only 2 to 5 kilograms of fish, so they are forced to use electricity and gillnets,” Kyaw Hla Thein explained.
“Even though the Department of Fisheries, in collaboration with us, has caught and fined the fishermen, use of prohibited methods to fish is still happening. We can’t blame them alone, as we’ve witness the scarcity of fish stocks. If we can’t control the environmental destruction, the situation will worsen,” he added.
Dwindling fisheries are not only affecting the livelihoods of Irrawaddy dolphins and fishermen. A centuries-old tradition of man-porpoise cooperation is also under threat. Conservationists say the number of locals who practice a form of symbiotic fishing with the dolphins is falling.
“Fishing with the Irrawaddy dolphins is now just for show to foreigners, and you will sadly witness only a few fish caught this way,” said Su Hlaing Myint, an independent researcher on Irrawaddy dolphins, who works in collaboration with the Mandalay-based NGO Green Activities.
“This lovely tradition is dramatically fading away and we fear for its extinction, together with the Irrawaddy dolphins. … To save the Irrawaddy River and Irrawaddy dolphins, urgent attention is needed,” she added.