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.

Gephyreus Project Launches Website on Lahille’s Bottlenose Dolphins

Pedro Fruet

In January 2025, the Gephyreus Project reached a significant milestone with the launch of its dedicated website, www.gephyreus.org /en, a platform designed to advance the conservation of Lahille’s bottlenose dolphins (Tursiops truncatus gephyreus). This vulnerable subspecies is endemic to the coastal waters of Brazil, Uruguay, and Argentina, and its small, isolated populations face severe threats from human activities. Fishery bycatch and habitat degradation are increasing throughout the dolphins’ range, underscoring the urgent need for regional and international collaboration in research and conservation action.

Lahille’s bottlenose dolphin in the Patos Lagoon. Photo Credit: Pedro Fruet

The new website is meant to serve as an informative and interactive hub for both the scientific community and the general public. It provides insights on the subspecies ecology, behavior, and distribution as well as information on conservation challenges and ongoing  research and conservation efforts. As part of the scientific content available in the library, the website features the 5-year Action Plan and the Conservation Management Plan (CMP) for Lahille’s bottlenose dolphins. This CMP, which was developed as an initiative of the International Whaling Commission (IWC), provides a structured framework for international cooperation in mitigating threats and coordinating research.

The website encourages active engagement with the Gephyreus network. Visitors can subscribe to the newsletter for updates on findings and conservation actions, donate to support research, or participate in programs such as Adopt-a-Lahille Dolphin, which allows supporters to track key life events of individual dolphins and contribute directly to their protection.

Lahille’s bottlenose dolphins in their typical nearshore habitat, which brings them into contact with a range of human activities. Photo Credit: Pedro Fruet

The survival of Lahille’s bottlenose dolphins depends on coordinated efforts across nations, disciplines, and communities. By launching this new digital platform, the project aims to strengthen connections among researchers, conservationists, policymakers, and ocean advocates. CSG members (and others who view this website) are invited to explore the website and engage with its available resources.

Lahille’s bottlenose dolphin mothers and calves in shallow  coastal waters in Argentina. Photo Credit: Sebastian Leal

ACTIONS TAKEN BY GOVERNMENT OF MEXICO REMAIN INSUFFICIENT TO SAVE THE VAQUITA

By: Lorenzo Rojas-Bracho and Barbara Taylor

On 3–8 February 2o25 the 78^th meeting of the CITES Standing Committee will consider Mexico’s September 2024 Progress and Results Report on its Compliance Action Plan to Prevent Fishing for and Illegal Trade in Totoaba, their Parts and/or Derivatives, to Protect the Vaquita (E-SC78-12-01-A8). In both 2023 and 2025 the CITES Secretariat gave high marks to Mexico (SC78 Doc. 33.12.1 Annex 9) for its implementation of many of the actions described in the CAP. However, a detailed analysis in 2023 by Rojas-Bracho and Taylor found that Mexico’s Progress and Results Report could mislead CITES Standing Committee members (and others) about the extent and effectiveness of conservation actions.

The new administration in Mexico has just begun its term and, unlike previous administrations, has already engaged on vaquita issues.  The updated report by the past administration which will be considered at this year’s CITES meeting raises concerns similar to those noted two years ago.

• • Gillnets continue to be used for fishing throughout the Upper Gulf, except within the Zero Tolerance Area (ZTA, including the so-called Extension Area).  For an analysis of fishing in the Vaquita Refuge that disputes what is reported by the Mexican Government’s Report to CITES in 2025 see: https://cetact.org/library/Mexico%20has%20under-reported%20gillnetting%20in%20the%20Vaquita%20Refuge.pdf
  • No significant progress has been made in transitioning fishing communities to alternative, vaquita-safe gear.

• • Without alternative gear, fishers feel compelled to continue using gillnets. Concentrating effort and resources on enforcement rather than on enabling fishers to transition to alternative methods will perpetuate a cycle where illegal fishing with entangling gear is nearly impossible to eliminate.
  • Devoting all compliance and enforcement effort solely to the ZTA will not enable the vaquita population recover or ensure that the totoaba fishery is sustainable.

Expansion of compliance and enforcement beyond the ZTA has taken on new importance because fewer vaquitas were observed within the ZTA in the 2024 survey (read the full report here in English and here in Spanish plus the Appendices here in English only) while acoustic monitoring outside the ZTA (acoustic report here in English and here in Spanish) detected vaquitas in areas that, although within the Vaquita Refuge, are not yet protected by concrete blocks with hooks to prevent the setting of gillnets.

Two recent publications urge that more funding be devoted to research on the ecological aspects of vaquita habitat on the premise that species recovery may not be possible even if the gillnets that kill vaquitas are removed. Rodríguez-Pérez et al. (2024) and Arreguín-Sánchez et al. (2025) argue that habitat changes in the Upper Gulf of California resulting from the damming of the Colorado River have sealed the fate of the vaquita.  Because these papers could influence the thinking of CITES Standing Committee members, we prepared a document to set the record straight: there is no evidence that vaquitas are nutritionally stressed.

In 2023, the Cetacean Specialist Group sent a letter to the CITES Secretariat expressing concern and supporting the analysis by Rojas-Bracho and Taylor of Mexico’s implementation of its Compliance Action Plan. That letter and analysis are available here. A new letter sent to the Secretariat is available here.

REFERENCES

Arreguín-Sánchez F, Zetina-Rejo n MJ, Vergara-Solana FJ, Del Monte-Luna P, Rodríguez-Fuentes M, Arreguín-Rodríguez GJ, Medina-Contreras D and Sánchez-Velasco L, (2025) State of knowledge of the population of the vaquita (Phocoena sinus) from the Upper Gulf of California: a bibliometric analysis. Front. Conserv. Sci. 5:1480035. doi: 10.3389/fcosc.2024.1480035

Rodríguez-Pérez M-Y, Sánchez-Velasco L, Rosas-Hernández M-P, Hernández-Camacho CJ, Cervantes FA, Gallo-Reynoso JP, Arreguín-Sánchez F and Godínez VM. 2024. Stable isotopes of carbon (d13C) and oxygen (d18O) from vaquita (Phocoena sinus) bones as indicators of habitat use in the Upper Gulf of California. Front. Conserv. Sci. 5:1490262. doi: 10.3389/fcosc.2024.1490262