Fig. 4. Example from a weekly HAB bulletin reporting HAB events along the Irish coast (courtesy of Dave Clarke) harvested along the coast. Analysis of seawater and oyster samples confirmed high levels of PSP toxins (Margarita Fernández-Tejedor). The design, implementation, and contents of HAB bulletins and early warning systems, including best practices guidelines on the development of weekly reports and forecasts, were reported for Scotland (Callum Whyte) and Ireland (Dave Clarke) (Fig. 4). Opportunities for improved forecasts of Dinophysis blooms in the Gulf of Mexico were shown with modelling approaches using temperature and prey size (James Fiorendino). More dedicated discussions took place in the special session on HAB Early Warning Systems chaired by Aurelia Tubaro and, Marie-Yasmine Dechraoui-Bottein. Satellite surveillance of algal blooms in lakes and coastal waters was shown to have great potential for HAB monitoring. Particularly during COVID when human activity in the field was restricted, a new satellite Copernicus Sentinel-2 with a pixel size of only 20 m, compared 8 to 200 m in previously used satellites, increased the number of lakes that could be monitored for algal blooms many-fold (Michelle Tomlinson). For the assessment of the economic threat of diarrhetic shellfish poisoning (DSP), a financial-DSP-shellfish production model was developed for Scottish shellfish production. This model facilitated the investigation of the effect of DSP levels on shellfisheries closures and associated reductions in shellfish production in money equivalents. The model showed that a 1% increase in DSP toxin levels over the regulatory threshold reduced production by 1,080 tons, 15% of Scottish shellfish production (Keith Davidson). A number of presentations showed that multi-sensor observations provide insights into bloom dynamics and raise new questions, especially about decoupling between cells, toxins, and shellfish. This was also highlighted in the special session on the national HAB sensor network of the United States (Michael Brosnahan). New develop- ments were presented for the Imaging FlowCytobot, which showed continued operation for 6 months, handling over 60 samples a day covering size ranges of 5-150 μm (Gregory Doucette). Results from the Environmental Sample Processor (ESP) showed its applicability for high frequency sampling, with over 60 samples analyzed per deployment, with near real time monitoring of species and toxins using specific nucleic acid markers (Nicolaus Adams). Nanotube based electrochemical sensors were presented for rapid, sensitive and low cost analysis of HABs and their toxins (Mònica Campàs). Improved RNA detection of toxic species using magnetic microbeads and amperometric detection at screenprinted carbon electrodes were able to detect as low as five cells per liter for some species. This fast, simple, and cheap methodology can be integrated in easy-to-use portable systems (Linda Medlin). Various mitigation strategies for harmful cyanobacterial blooms were presented. This included the payment HARMFUL ALGAE NEWS NO. 69 / 20221 Harmful Algae News An IOC Newsletter on Toxic Algae and Algal Blooms No. 69 - February 2022 https://hab.ioc-unesco.org/ The 19th (1st Virtual) International Conference on Harmful Algae hosted from Mexico The 19th International Conference on Harmful Algae (19 ICHA), was held in a virtual format for Lobby of the virtual ICHA 2021 costs to attend the meeting. The Conference started with two pre-conference sessions of the Young Investigator Networking Session coordinated by Lorena Durán, Carlos Rodríguez, Philipp Hess, and Harry Nelson. Previously, Lorena Durán and Carlos Rodríguez interviewed o The Mexican scientists comprising the Local Organizing Committee special sessions held live on Zoom that covered breakthrough topics on harmful algae from marine and freshwater environments: HAB Early Warning Systems Session, Impacts of HABs on fish farms: Addressing industry and global insurance n Scientific Highlights of the 19th International Conference on Harmful Algae Summarizing all of the science from a conference is a huge and perhaps impossible task, but once done, it can serve as a reference for the future. We had five exciting and intensive virtual conference days where all the late predatorial protists, viruses, and bacteria (Alexandra Worden). Several plenary talks highlighted insights on HAB management, including emergent management strategies for monitoring, biotoxin detection, and human health risks associated with Ciguatera Poisoning (Marie-Yasmine Dechraoui Bottein); com Fig. 2. Long-term history of HABs off Eastern Tasmania, Australia, using sedimentary DNA (courtesy of Linda Armbrecht) French Mediterranean and a French Atlantic K. veneficum strain induced over 50% loss of cell viability. A high level of intra-specific variability of ichthyotoxic activity was obse pacificum and Durusdinium trenchii) to be successfully frozen and revived with high viability (Joseph Kihika). This highlights the potential to have a microalgae diversity bank in the future. Several presentations were focused on the intimate association between hosts and their microbiomes (Chri Fig. 4. Example from a weekly HAB bulletin reporting HAB events along the Irish coast (courtesy of Dave Clarke) harvested along the coast. Analysis of seawater and oyster samples confirmed high levels of PSP toxins (Margarita Fernández-Tejedor). The design, implementation, and contents of HAB bulle for lake ecosystem services and selection of environmental measures together with local farmers, which may reduce overall costs (Claudia Wiegand). A special session on the new WHO book Toxic cyanobacteria in water provided advice and guidelines for the management of freshwater cyanobacterial blooms, ISSHA's Corner The International Society for the Study of Harmful Algae (ISSHA) convened the 19th (1st Digital) International Conference on Harmful Algae (19 ICHA), held in La Paz, México, from 10th to 15th October 2021. The ISSHA Council had monthly meetings on-line between May and October to plan molecular probes targeting HAB species (including their different life cycle stages), difficult to identify with conventional microscopy methods. More information about Lindas biography and publications can be found here. Nomination letter of Linda Medlin to the ISSHA Council There are many, many re waters of the South China Sea, a marginal sea of the Western Pacific (Teng et al. 2013, 2014). Sing Tung Teng has demonstrated his training and dissemination skills by introducing a taxonomic grouping of Pseudo-nitzschia based on frustule morphology, which eventually developed into an interactive ke from some species of Rhodophyta to the cultures significantly enhanced the growth of the two Gambierdiscus species that occur in Japan. He is now starting an investigation to clarify the effect of bacteria on Gambierdiscus growth in an attempt to elucidate the growth characteristics of Gambierdiscus ISSHA President goodbye Dear ISSHA members: As many of you know, at the general glection held prior to the International Conference on Harmful Algae (ICHA2021) from 11-15 October 2021 (La Paz, Mexico), I stepped down as the president of the International Society for the Study of Harmful Algae (ISSHA UNESCO Taxonomic Reference List of Harmful Micro Algae Editors Workshop 2021 On November 18-19th 2021, the nine thematic editors responsible for the UNESCO Taxonomic Reference List of Harmful Micro Algae and Henrik Enevoldsen from IOC-UNESCO gathered together in a hybrid format workshop, to discuss Book Review: A Catalogue of Phytoplankton from the Mexican CentralPacific (in Spanish) Authors: Hernández-Becerril, D.U., Barón-Campis, S.A., Ceballos-Corona, J.G.A., Alonso-Rodríguez, R., RinconesReyes, K.M., Becerra-Reynoso, R.T. & Arce-Rocha, G. 2021. Catálogo de fitoplancton del Pacífico central Forthcoming Events 2022 UN Ocean Conference GLOBAL ONLINE STAKEHOLDER CONSULTATION Inputs to concept papers of interactive dialogues Contribute your inputs to the concept papers of the interactive dialogues for the 2022 UN Ocean Conference! (see back page) Deadline: 21 February 2022 Contribute your GlobalHAB symposium on automated in situ observations of plankton Aims and background Harmful Algal Blooms (HABs) are affecting aquatic ecosystems and human societies. Biotoxin-producing HABs species and species causing fish mortalities are problems for aquaculture, fisheries and also for tourism. H www.neiwpcc.org/events/ushab11 #USHAB2022 For logo contest rules, please visit our conference website. We are pleased to announce that the 11th U.S. Symposium on Harmful Algae will be held on October 23-28, 2022 in Albany, New York, at the Hilton Albany. Local coordination is being led by NEIWPCC, Eds-in-chief Beatriz Reguera, IEO (CSIC), Vigo, Spain Eileen Bresnan, Marine Scotland, UK Regional Editors Caribbean: Ernesto Mancera jemancerap@unal.edu.co Atlantic Europe: Maud Lemoine Maud.Lemoine@ifremer.fr Mediterranean Sea: Adriana Zingone zingone@szn.it India: K.B. Padmakumar kbpadmakumar