morphological and molecular identification of benthic Prorocentrum and cyanobacteria with measurements of dissolved inorganic nutrients, dissolved and particulate organic carbon, phycotoxins, microbial community composition, sediment resuspension, and water-exchange and salinity dynamics. Acknowledgements We would like to express our gratitude to Jairo Humberto Medina-Calderon, director of the San Andrés Botanical Garden, for his support during the sampling, to Jhon Anderson Aragon from the SEM laboratory of the Faculty of SciencesUNAL, to Juan Carlos Mejía for the observation of satellite images from March, April, and May 2026, which helped detection of the reddish discol- oration of the Old Point lagoon, and to Taiara Aguiar Caires from Universidade Federal da Bahia, Brazil, for the provisional identification of the cyanobacterium. This work was conducted as part of the project Valuation of the ecosystem services of biodiversity, climate regulation, and coastal erosion control in coastal wetlands of the oceanic and continental Caribbean of Colombia (Hermes Code 51856). References 1. Youssef NH et al. 2012. Appl Environ Microbiol 78(5):13321344. https://doi. org/10.1128/AEM.07420-11 2. Hoppenrath M et al. 2013. Harmful Algae 27:128. https://doi.org/10.1016/j. hal.2013.03.006 3. Tarazona-Janampa UI et al. 2020. Front Mar Sci 7:569. https://doi.org/10.3389/ fmars.2020.00569 4. Camacho-Muñoz D et al. 2021. Front Mar Sci 8:638739. https://doi.org/10.3389/ fmars.2021.638739 5. Nascimento SM et al. 2016. Harmful Algae 57:3948. https://doi.org/10.1016/j. hal.2016.05.006 Authors José Ernesto Mancera Pineda, Brigitte Gavio, Dannys Alejandra Herrera, Wilson Alejandro Pacheco & Luisa F. Dueñas. Department of Biology, Universidad Nacional de Colombia. Corresponding author: jemancerap@unal.edu.co https://doi.org/10.5281/zenodo.22814511 Remembering Dr Shelly-Ann Cox Dr Shelly-Ann Cox, Chief Fisheries Officer of Barbados and an esteemed fisheries scientist, passed away unexpectedly on 13 June 2026 at the age of 37. Dr Cox lived and worked to improve the lives of all those who made their living from the sea. An academic of the highest order, her true greatness laid in her compassion, humility, and fierce commitment to ordinary fishers. Whether dealing with the deep ocean or the challenges faced along the shore, she defended the dignity, livelihoods, and futures of real families and communities. Dr Cox made a foundational contribution to the Sargassum community. She was the leading author of the landmark 2021 white paper Turning the Crisis into an Opportunity, presented at the Ninth Meeting of the Scientific and Technical Advisory Committee (STAC) to the Protocol Concerning Specially Protected Areas and Wildlife (SPAW) in the Wider Caribbean Region in Kingston, Jamaica. She was also a lead author of the 2024 IOC UNESCO white paper Addressing the influxes of the holopelagic Sargassum spp. in the Equatorial and HARMFUL ALGAE NEWS NO. 84 / 2026 Subtropical Atlantic: recent scientific insights in their dynamics. From early stages of her career, she understood the vital importance of mobilizing decision-makers. She had a remarkable ability to explain the complexities of valorization while clearly articulating the immense opportunities that this crisis could represent. As Chief Fisheries Officer of Barbadosone of the countries hardest hit by massive Sargassum influxes and beach accumulationsshe occupied a uniquely important position at the intersection of science and decision-making. She was uniquely capable of understanding the needs of local communities, the science behind the challenges facing our oceans, and the opportunities that lay ahead. Our deepest sympathies go out to her son, her family, her friends, mentors and colleagues as well as to the wider Barbados community and the hardworking people she passionately supported. Henrik Enevoldsen 13 Harmful Algae News An IOC Newsletter on Toxic Algae and Algal Blooms No. 84 September 2026 https://hab.ioc-unesco.org/ Unveiling biotic controls of Alexandrium minutum in the Ría de Vigo (NW Spain) Understanding biotic interactions that regulate the dynamics of harmful algal bloom (HAB) species r Fig. 2. The study area in the Ría de Vigo (NW Spain). The red dots indicate the locations where the A. minutum strains were isolated. [1]. We propose that such stable abiotic conditions may facilitate the establishment and persistence of key biotic interactions between the microalgae and their micr Fig. 4. Abundance of Alexandrium minutum (Am) (A) and bacteria (B) in quasi-axenic monocultures (blue lines) or co-cultures with Alteromonas sp. (Alt) (red lines) with B-vitamins (w B-vit, solid lines) or without B-vitamins (wo B-vit, dashed lines). (C) Taxonomic composition of the bacterial microbi Fig. 5. Box and whisker plot showing the response ratios (RR) of Alexandrium minutum growth to the addition of different Zostera marina exudates at low (200300 μM DOC) and high (500600 μM DOC) concentrations. A total of 14 and 10 response ratios were included for the low and high concentration treat dinoflagellates. It has been suggested that phenolic compounds produced by marine angiosperms, e.g. [25], may play a significant role in the negative interaction between these plants and dinoflagellate growth [56, 21]. However, this hypothesis has not yet been experimentally tested. Acknowledgement Intense algal bloom during the austral summer in Inglesa and Calderilla Bays (Atacama, Chile): phytoplankton monitoring, environmental observations and implications for coastal aquaculture Fig. 1. Seawater discoloration in Inglesa Bay sector, Caldera during the first week of February 2026. (A) and Fig. 3. Dominant dinoflagellate species in the algal bloom. (A) Akashiwo sanguinea and (B) Tripos cf. furca. radically (2005, 2009, 2014, and 2016), including blooms of the toxic dinoflagellate species such as Protoceratium reticulatum, which produces yessotoxins (YTX) and has been detected along t Fig. 5. Abundance of other microplankton groups in February 2026 at the five sampling stations in the Caldera Bay System. 2. Rodríguez L 1978. Noticiario Mensual del Museo de Historia Natural de Chile 22(266):69 3. Rodríguez L 1985. Rev Biol Mar 21:173197. https://hdl.handle. net/20.500.14330/PER01 An overview of the 20182025 monitoring, detection, and control programme for Alexandrium catenella in Southern Chile The frequency, persistence, and geographical extent of harmful algal blooms (HABs) caused by the dinoflagellate Alexandrium catenella have increased in southern Chile over recent deca 3. 4. 5. 6. 7. 8. Fig. 2. Annual number of analysed samples and positive detections between 2018 and 2025. Bars represent the total number of samples collected each year. The red area indicates positive results (number shown at the base of each bar), whereas the blue area corresponds to negative res A mixed bloom of Prorocentrum lima species complex and Aphanocapsa sp. under hypersaline conditions in a mangrove lagoon of the Seaflower Biosphere Reserve, Colombian Caribbean Fig. 1. Old Point Regional Park, San Andrés Island, Seaflower Biosphere Reserve, showing the small mangrove lagoon where t Table 1. Measurements of physicochemical characteristics recorded during the mixed bloom of the Prorocentrum lima species complex and Aphanocapsa sp. Old Point, Colombia Lago delle Nazioni, Italy Paracas Bay, Peru 14 April 2026 December 2019 January 2020 2729 August 2017 4.5 106 4.7 107 2 morphological and molecular identification of benthic Prorocentrum and cyanobacteria with measurements of dissolved inorganic nutrients, dissolved and particulate organic carbon, phycotoxins, microbial community composition, sediment resuspension, and water-exchange and salinity dynamics. Acknowled Forthcoming IOC-FAO IPHAB The Eighteenth Session of the IOC-FAO Intergovernmental Panel on Harmful Algal Blooms (IPHAB-XVIII) will meet on 16-18 March 2027 at FAO Headquarters in Rome. The establishment of an intergovernmental panel on HABs in 1991 was a response to the need to improve the manageria The second International Conference on Ostreopsis Development ICOD 2, French Basque Country, June 1011, 2027 Over the last decades increasing attention has been paid to benthic dinoflagellates belonging to the genus Ostreopsis. The presence of these microalgae has been reported in many temperate re NEW! IOC Toxins database The IOC Toxins database is now on-line. It contains reference information about toxins, some of which are associated with Harmful Algal Events. The IOC Toxin Reference List is work in progress. Some sections are complete, some are partly complete and some are empty. The Lis