IUCN – SSC Cetacean Specialist Group

The Cetacean Specialist Group promotes and facilitates
The Cetacean Specialist Group promotes and facilitates
The Cetacean Specialist Group promotes and facilitate
The Cetacean Specialist Group promotes and facilitates
The Cetacean Specialist Group promotes and facilitates

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

2

 

By: Lorenzo Rojas-Bracho and Barbara Taylor

 

On 3–8 February 2o25 the 78th 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

New Findings Reveal Vaquitas Outside Protected Areas Following May 2024 Survey

9

Barbara Taylor and Lorenzo Rojas-Bracho

 

Given the 45% annual decline estimated in 2018, most people expected Mexico’s vaquita porpoise to be extinct by now. As vaquita numbers declined, the distribution of vaquita acoustic activity in the Vaquita Refuge shrank to the area currently known as Zero Tolerance Area (ZTA) (Jaramillo-Legorreta et. al. 2019). Between August 2022 and September 2024 the Mexican Navy deployed more than 400 concrete blocks with 3m high metal hooks designed to entangle gillnets within the ZTA and an extension area adjacent to the ZTA. Since then, the Navy and Sea Shepherd Conservation Society (SSCS) have collaborated to monitor fishing activity. Deployment of the gillnet-entanglement devices, which resulted in a 90% decrease in gillnetting within the ZTA, is probably the most significant recent step toward buying precious time for the new Government to take additional vaquita-protection actions.

 

In May 2023 scientists saw about the same number of vaquitas they had seen in 2019 and 2021 in the ZTA (read the full report here in English and here in Spanish plus the Appendices in English only). The May 2023 vaquita survey observed gillnets just outside the ZTA boundary, including in an area where a mother and calf were seen. This prompted the government to designate an Extension Area (EA) that was later seeded with more concrete blocks.

 

Figure 1. The Seahorse with crew on the bow and observation team on the bridge deck in the foreground and the Sirena de la Noche with the observation team on the bow in the background.

 

The May surveys in 2023 and 2024 were designed to be comparable using the same 2 ships, the Seahorse and the Sirena de la Noche (Figure 1), the same observers and the same methods (both surveys funded by CONANP and SSCS). Weather was also comparable with a bit more coverage in good sea states in 2024 than in 2023. In May 2024, there were 9 sightings of vaquitas within the ZTA and the Extension Area (read the full report here in English and here in Spanish plus the Appendices here in English only) (Figure 2) compared to 16 sightings in 2023. Results from Expert Elicitation of the 2024 survey data indicated that it was highly likely that no calves were seen, one yearling was seen and there was a 75% probability that the total number of vaquitas seen was between 6 and 8 individuals. 6-8 is considered a minimum estimate of the number of vaquitas left. The 2024 estimate is less than the 10-13 that were seen in 2023 within a similar area. All the animals looked healthy and they were apparently feeding.

 

Figure 2. Summary of vaquita acoustic and visual detections during the May survey. The ZTA is within the yellow corner dots. Corners of the Extension Area (EA) are indicated by red dots. Black dots are positions for survey navigation some of which correspond to locations of acoustic detectors. Sites with acoustic detections are green dots. Sightings (purple dots) 3, 4, 5 and 7 were in the EA and sighting 6 was along the boundary of the ZTA. Tracklines of the Seahorse are in red and the Sirena de la Noche in blue. San Felipe harbor is the small square at the bottom of the figure.

 

The authors of the 2024 Report cautioned that the reduced number of vaquitas detected within the ZTA plus EA doesn’t necessarily represent a further decline since the surveyed area represents only 12% of the species’ range in 2015 (Rojas-Bracho et al. 2024). Following recommendations within the survey report, acoustic research outside the ZTA was conducted (acoustic report here in English and here in Spanish). In late August and early September passive acoustic detectors had vaquita detections both within the ZTA and in areas within the Vaquita Refuge that were previous high vaquita use areas. Finding that vaquitas are using their former range gives hope that the reduced numbers seen in the May 2024 survey may not represent reduced numbers of vaquitas remaining. However, given that there is no evidence of reduced levels of gillnetting except within the ZTA and part of the Extension Area, additional protective measures will be needed for vaquitas found outside these areas in the Vaquita Refuge.

 

Citations:

Rojas-Bracho et al. 2024. Mexico must save the vaquita from gill nets. Science Vol 385, Issue 6708, p 504. DOI: 10.1126/science.adp5382.

 

Jaramillo-Legorreta, A.M., G. Cardenas-Hinojosa, E. Nieto-Garcia, L. Rojas-Bracho, L. Thomas, J.M. Ver Hoef, J. Moore, B. Taylor, J. Barlow, N. Tregenza. 2019. Decline towards extinction of Mexico’s vaquita porpoise (Phocoena sinus). R. Soc. Open sci. 6: 190598.

Scientists galvanise to conserve Endangered Indian Ocean humpback dolphins

2

Like these in Dubai, UAE, humpback dolphins live very close to shore, often close to cities (Photographer: Ada Natoli).

Indian Ocean humpback dolphins (Sousa plumbea) are assessed as Endangered on the IUCN Red List, meaning they are among the species of greatest conservation concern globally.  The species range spans from the southern tip of Africa to the southern tip of India, including the Red Sea, Arabian/Persian Gulf and some islands, such as Madagascar, Sri Lanka, Zanzibar, Socotra and Mayotte. Many of the 23 range countries are low-income states.

These dolphins occur mainly in shallow water less than 25m deep, and they favour estuaries, coral reef and rocky shore habitats, lagoons, and shallow sheltered bays.  In most places where data are available, populations are small and declining because of their proximity to highly populated coastlines and exposure to numerous threats.  Significant gaps exist in knowledge, capacity and resources.

To galvanise conservation action, in early 2024, researchers and conservationists working on the species formed the Indian Ocean Humpback Dolphin Conservation Network (HuDoNet). In total, 72 scientists from 17 countries in the western Indian Ocean and Arabian Sea are now working together under HuDoNet’s umbrella.

The aim of HuDoNet is to foster and facilitate collaborative research and management efforts by sharing expertise and working together across the species range, attracting resources to support local initiatives. By unifying and amplifying the voices of individual researchers the hope is to draw attention to the needs of humpback dolphins.  The network created a logo (see below) and website: hudonet.org.

The main immediate task of the group is to set short- and medium-term targets for action in the form of a Network Action Plan. To do this, HuDoNet has established five working groups:

Indian Ocean Humpback dolphins in Tanzania (Photographer: Gill Braulik)

  • Biological Research;
  • Threats and Solutions;
  • Policy;
  • People; and
  • Network Success.

 

Each working group is undertaking the process of:
1) collating and synthesising available data to highlight gaps and opportunities for action;
2) identifying leverage points and weighing up the costs, benefits and feasibility of potential interventions, and
3) specifying the resources and capacity required for prioritised actions.

Working group meetings have been convened throughout October and November and connections are being made within this large, culturally diverse, widely dispersed group of people – a crucial step towards achieving HuDoNet’s mission of ensuring a future for Indian Ocean humpback dolphins throughout their range.  To learn more or to provide assistance or support please explore the website: www.hudonet.org.

Shipping and associated infrastructure are among the many threats to the Endangered Indian Ocean humpback dolphins (Photographer: Brett Atkins)

 

Subscribe

[mc4wp_form id="348682"]

IUCN – SSC Cetacean Specialist Group

The Cetacean Specialist Group promotes and facilitates the conservation of cetaceans worldwide. It functions as a catalyst, clearing house, and facilitator for cetacean-related research and conservation action.

LATEST UPDATES FROM BLUESKY

@iucn-cetaceansg.bsky.social 1/3
The IUCN published Red List update 2025-2 on October 10th, coinciding with the 2025 World Conservation Congress.
Nov 28, 2025
Follow

Latest Post

logo COPYRIGHT IUCN -CSG. DEVELOPED BY SIMPLY IT LIMITED 2019