Swimming for Irrawaddy dolphins in the Mekong River

By Brian Smith, Frances Gulland and Jason Allen

Since 2009, the IUCN Cetacean Specialist Group has provided technical support for conserving a Critically Endangered population of Irrawaddy dolphins in the Mekong River (see more information on the CSG Focal Taxa page: here). Despite research and conservation efforts carried out by WWF Cambodia and the Cambodian Fisheries Administration, the population continues to be threatened by entanglement in gillnets. One of the most effective approaches to reduce this threat has been patrols conducted by river guards, comprised of fishery and police officers, and community members, who enforce the ban on gillnets in core habitat of the dolphins. However, funding constraints have limited the effectiveness of the river guard program and entanglement in gillnets remains the most immediate threat to the survival of the dolphin population.

The swim was launched with an official ceremony bringing together government and NGO stakeholders.

To raise the profile of dolphin protection efforts and funds to support the river guard program, during 17-20 March 2025, a small team of scientists, representing the IUCN SSC Cetacean Specialist Group and Wildlife Health Specialist Group and Brookfield Zoo Chicago’s Sarasota Dolphin Research Program, as well as conservation supporters, swam downstream along 120 kilometers of the current range of Irrawaddy dolphins in the Mekong River. Along the way, they stopped in villages and towns to participate in awareness raising activities organized by WWF Cambodia, the Ministry of Agriculture, Forestry and Fisheries, and Provincial Governors. The experience of swimming in the river, navigating its strong currents, and occasionally dodging gillnets in the deep pools where the dolphins occur, gave the team a much greater appreciation of the survival challenges faced by the population. Visiting villages that depend on riverine fisheries also gave them an appreciation of the need for alternative livelihoods in fishing communities affected by the ban on gillnets. The enthusiasm of local communities for the swim and participation of high-level government officials in awareness raising events gave the team hope for the success of efforts to protect the dolphin population from extinction.

For more information see this WWF Press Release or watch this inspiring video.

Irrawaddy dolphin surfacing behind the support boat.

A swimmer with the support kayak and a typical Cambodian temple in the background.

Swimmers with school children in one of the villages along the swim route.