Human-dolphin Partnership Inspires Government Protection
The small, gray, beakless Irrawaddy dolphins have a knack for herding fish into nets, explaining their usefulness to fishermen, according to the organization.
The government decreed protection for some 70 kilometers of Myanmar’s Ayeyarwady River to safeguard a zone for cooperative fishing. The area supports one third of the river’s population of Irrawaddy dolphins, according to the group, a species threatened throughout much of its range.
“This is a big step forward toward saving this cetacean in the Ayeyarwady River and the fishery that benefits both humans and dolphins,” said the society’s Brian D. Smith, who has researched the dolphins for several years.
Fishermen summon the mammals to voluntarily herd schools of fish toward the boats and awaiting nets. With the dolphins’ help the fishermen can increase their hauls threefold, according to Smith; the dolphins seem to benefit by easily catching cornered fish in nets and on the muddy riverbanks.
The dolphin grows to some 2 to 2.5 meters in length (6.5 to 8 feet) and frequents the coasts, estuaries, and freshwater lagoons of Southeast Asia, according to Smith. It’s threatened throughout its range by incidental catches and in several areas by habitat degradation.
The Ayeyarwady River population is one of the most threatened, according to the society: electrocution from illegal electric fishing and entanglement in gill nets, mercury poisoning and habitat loss from gold mining have devastated the animals.
Recent surveys found that the species range had declined by some 60 percent, according to the group. That prompted the World Conservation Union to designate the river population “critically endangered.”
A recent ban on gold mining in the Ayeyarwady has successfully eliminated that threat at least, according to the Wildlife Conservation Society. The protection decree will enforce the prohibition of electric fishing, gold mining and other threats, the group added, as well as initiate systematic monitoring for the species and raise awareness.
If the protected area proves successful, “it could be used as a model for extending similar protection to other river segments,” said U Mya Than Tun, senior scientist with the Myanmar Department of Fisheries.
- Courtesy Wildlife Conservation Society
and World Science staff