Escalating Threat to Marine Wildlife from Trade Demand for Croaker Fish Swim Bladders

Vaquita and tototaba on a totoabera net. Photo: O. Vidal


The CSG has a long history of engaging in efforts to save the vaquita porpoise from extinction due to bycatch in gillnets targeting the totoaba croaker for its swim bladder or maw. Earlier this month, a letter was sent to the CITES Standing Committee expressing our concern about Mexico’s compliance with its “Action Plan to Prevent Fishing for and Illegal Trade in Totoaba, their Parts and/or Derivatives, to Protect the Vaquita”. Also this month, Brian Smith, Cetacean Specialist Group Asia Co-coordinator and Director of the Wildlife Conservation Society’s (WCS) Marine Wildlife Bycatch Reduction Initiative, together with co-authors from Bangladesh, published a journal article pointing out that the heightened value of croaker swim bladders is contributing to the endangerment of numerous other marine species, including globally threatened dolphins, porpoises, sharks, rays, marine turtles, and other croakers with valuable maws. One of the co-authors, Elisabeth Fahrni Mansur, is Regional Vice-Chair for the Indian Ocean of the IUCN Shark Specialist Group.

Irrawaddy dolphins are frequently bycaught in coastal gillnet fisheries in Bangladesh that also catch Black-spotted croakers with maws selling to international traders for up to several thousand USD each. Photo credit: WCS Bangladesh


Gillnet fisheries and other coastal fisheries that catch croakers with high-value maws are intensifying in several areas, driven by the enormous demand, primarily in China, for croaker maws as a luxury or status food and a profitable financial investment. This is exacerbating a conservation crisis already facing cetaceans and other marine wildlife due to fishery bycatch. An IUCN motion on monitoring and controlling trade in croaker swim bladders was approved at the 2021 IUCN World Conservation Congress. This motion called on member nations to support the establishment of trade regulations on croaker fish maws through national laws and CITES regulations.

To further investigate the link between the trade demand for croaker maws and fisheries that bycatch threatened marine wildlife, including cetaceans, an online survey will soon be circulated to the CSG and members of other relevant IUCN specialist groups. Information from this survey will enable the CSG and others to address this rapidly growing threat more effectively.


Smith, B.D., Mansur, E.F., Shamsuddoha, M. & Billah, G.M.M. (2023). Is the demand for fish swim bladders driving the extinction of globally endangered marine wildlife? Aquatic Conservation: Marine and Freshwater Ecosystems, 1–6.

Actions taken by Government of Mexico are insufficient to save the vaquita


On 6-10 November the CITES Standing Committee will consider Mexico’s August 2023 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 (No. 2023/112 Mexico Compliance Action Plan, CAP). The CITES Secretariat gave high marks to Mexico for its implementation of many of the actions described in the CAP. However, a detailed analysis by CSG members Lorenzo Rojas-Bracho and Barbara Taylor found that the CAP will mislead CITES Standing Committee members (and others) about the extent and effectiveness of conservation actions.


The main concerns are:

  • gillnets continue to be used, wantonly and extensively, for catching fish and shrimp except within the (very small) Zero Tolerance Area (“ZTA”);
  • no significant progress has been made toward transitioning communities to alternative fishing gear;
  • focusing compliance and enforcement effort solely on the ZTA will not result in vaquita recovery or in sustainable management of totoaba; and
  • monitoring of vaquitas (acoustically and visually) continues to be impeded by fishing activity.


The Cetacean Specialist Group has written a letter to the CITES Secretariat expressing concern and supporting the analysis by Lorenzo Rojas-Bracho and Barbara Taylor of Mexico’s implementation of its Compliance Action Plan. The letter and analysis are available here.

Red List Status and Extinction Risk of the World’s Whales, Dolphins and Porpoises – New Infographic


From 2017 to 2021, the CSG reassessed nearly all currently recognized species of cetaceans (90 of 92 at that time) for the IUCN Red List. Regular updates regarding progress on this task, which involved many CSG members, have been provided on this website (see 2022, 2021, and 2020 updates on red listing progress). With the task close to completion, the information contained in the newly updated Red List assessments was collated to provide an overview of the global Red List status, which was published in Conservation Biology earlier this year in a paper with the title Red List Status and Extinction Risk of the World’s Whales, Dolphins and Porpoises.


The key findings of the paper are shown in the bullet points below. To aid in communication of the findings and to highlight important issues to decision makers and the public the infographic below was also developed. This infographic is available for download and we encourage everyone to use it.


Key Findings

    • One in 4 cetacean species (26% of 92) were assessed as being threatened with extinction (i.e., Critically Endangered (CR), Endangered (EN), or Vulnerable (VU)) and 11% as Near Threatened (NT).
    • Ten percent of cetacean species were assessed as Data Deficient, and it was predicted that 2–3 of these species may prove to be threatened.
    • The proportion of threatened cetaceans has increased: 15% in 1991, 19% in 2008 and 26% in 2021.
    • The assessed conservation status of 20% of species has worsened from 2008 to 2021, and only 3 moved into categories of lesser threat.
    • Cetacean species with small geographic ranges were more likely to be listed as threatened than those with large ranges.
    • Cetacean that occur in freshwater (100% of species) and coastal (60% of species) habitats were under the greatest threat.
    • Analysis of odontocete species distributions revealed a global hotspot of threatened small cetaceans in Southeast Asia, in an area encompassing the Coral Triangle and extending through nearshore waters of the Bay of Bengal, northern Australia and Papua New Guinea and into the coastal waters of China.