Remote sensing of recurrent cyano HABs in Patos Lagoon, Brazil Fig. 1. Map of Patos Lagoon (southernmost part of Brazil) taken from [7]. Black circles indicate the four sites chosen forNDCI values retrieval [4]. Every austral summer, dense surface growth and accumulations of cyanobacteria threaten public health and local economic and leisure activities in the Patos Lagoon system (PL) in the southernmost part of Brazil (Fig. 1) [1]. Microcystis and Dolichospermum species can be the main components of these cyanobacterial harmful blooms (cyanoHABs). Microcystis species produce microcystins and Dolichospermum species, saxitoxins [2,3]. Due to the great spatial coverage of PL by these blooms, in situ studies and monitoring programs for cyanoHABs are major tasks that require resources that are not always available. We are conducting studies using relatively new tools, remote sensing and modeling, that can jointly address two important questions: 1) To what extent can the spatial and temporal distribution pattern of cyanoHABs be better un- Fig. 2. Bloom on the Tavares margin, on December 30th 2019 (Source: a local, anonymous inhabitant). 14 derstood? 2) Are distribution patterns being modulated by climate change? We used an index of phytoplankton biomass derived from Sentinel-2 images, i.e., the Normalized Difference Chl-a Index (NDCI) [4], for the central part of PL spanning July 2019 to June 2020 (Fig. 1; see all four sites chosen for retrieving NDCI and water temperature values). NDCI, where values greater than 0 imply bloom occurrence, is based on the use of the 708 nm and 655 nm bands combined to evaluate bloom status in the water. We observed two cyanoHAB events during the summer of 2019 2020: one on the east (Tavares town) on December 30th 2019 (Fig. 2) and the other on the west margin (Arambaré town) on January 10th 2020 (Fig. 3). To correlate meteorological data with the NDCI index, two meteorological stations were considered: Mostardas for the Ta- vares and Camaquãfor the Arambaré bloom events, both for the same time period. In addition, a 30-year meteorological time series of data assembled from the literature was retrieved with a closer grid point for the two locations [5]. The available information included rainfall (19802015), air temperature (19802013) as well as wind speed and direction for the summer 20192020. This approach helped us to classify the years 2019 and 2020 within a changing climate scenario. Lastly, water temperature values for 2019-2020 were obtained using MODIS (Moderate Resolution Imaging Spectroradiometer)-Terra imagery. Preliminary findings showed strong winds (>6 ms-1) were recorded before the observed blooms, followed by relatively weak winds (<<6 ms-1) during the bloom days. Thus, calm winds would have allowed the growth and surface accumulation of phytoplankton cells (Fig. 4). NDCI peaks coincided with the highest water temperature values, confirming an expected correlation between high temperatures and exponential cyanobacterial growth, especially near the margin of Tavares town (Fig. 5) [3,6]. We concluded that in a climate change context, summer 20192020 was drier in comparison to the historical mean, in particular during November-December 2019 and February 2020. Meanwhile, Tavares region showed a negative (-100-mm) anomaly in cumulative rainfall during the summer. Currently we can state that relatively weak winds and low rainfall, especially in Tavares (highest NDCI values) contribute to bloom formation. This is possibly due to the increase of water residence time within PL, a situ- Fig. 3. Sentinel-2 image on January 10th 2020 depicting NDCI features across the central part of the PL system, particularly near the west margin, including Arambaré town (see Fig. 1). Unfortunately, there was no image available for December 30th 2019. HARMFUL ALGAE NEWS NO. 67 / 2021 Harmful Algae News An IOC Newsletter on Toxic Algae and Algal Blooms No. 67 - April 2021 www.ioc-unesco.org/hab SHIOHIGARI and PSP toxins in Japan: Initiatives to save traditional recreatio nal clam picking Shiohigari has been enjoyed by people in Japan for centuries, as depicted in the Japanese a Fig. 2 Clamming parks in Osaka Prefecture (Modified from a digital map of The Geospatial Information Authority of Japan) ingly, they had developed the exchange system to secure viability of their operations before 2002 when PST exceeding the regulatory limit were first detected in clams from seas a Fig. 4 System of exchanging clams which secure food safety at Tannowa clamming park (Modified from [3} of visitors to clamming parks has now recovered. This is a success story of how to mitigate socio-economic impact on recreational clamming in Osaka prefecture due to PST. Thanks to the initiatives HABs and the Mixoplankton Paradigm Mixotrophs are defined as organisms that are able to use photo-autotrophy and phagotrophy or osmotrophy to obtain organic nutrients [1]. It is notable that all phototrophic protists are potentially mixotrophic if only through expression of osmotrophy enabled by the Fig. 2. Indication of proportion of IOC-UNESCO HAB species [6] assigned to each of the HAB plankton functional groups according to key in Fig.1 compiled by cross-reference to a database on mixoplankton species. CM, constitutive mixoplankton; pSNCM, plastidic specialist non-constitutive mixoplankton; Fig. 3. Schematics and model simulation outputs run under the traditional paradigm (left) versus the mixoplankton paradigm (right). See text for explanation. B bacteria; Phyto phytoplankton (non-phagotrophic phototroph); μZ protozooplankton; CM constitutive mixoplankton (photophago-trophic); DIM Tiny cells with a big impact: An unexpected bloom in the mid-Atlantic Fig. 1. a) Bongo nets fouled with the brown mucilaginous plankton. b) Dark and gelatinous content of the plankton nets scraped into a sample tray. Since 1992, the US NOAA Ecosystem Monitoring (EcoMon) cruises survey the Northeas Fig. 3. Scanning electron micrographs of frustules in valve view of Thalassiosira mala. Note the single eccentric strutted process (black arrow), the ring of marginal strutted processes (arrowheads) and the single labiate process (white arrow) located within the ring of marginal strutted processes s Acknowledgements We are grateful to Kyle Turner for helpful discussions regarding the fall 2018 EcoMon cruise and to Dr. Irene Andreu for SEM assistance. Dr. Paul E. Hargraves provided some insights on diatom taxonomy. We acknowledge the dedication of the crew of the R/V Sharp during a particularly First report of an Ansanella granifera bloom in Cuban waters, Caribbean region Fig. 1. Map of the study area showing the location where the dinoflagellate bloom o ccurred in southeastern Cuba. Harmful Algal Blooms (HABs) have been associated with fish and shellfish kills, ecosystem damage, human Fig. 3. Light microscopy images of fixed cells of Ansanella granifera. 4). Ansanella granifera is a dinoflagellate belonging to the family Suessiaceae (order Suessiales) that was recently described from Korea [5]. To our knowledge, the occurrence in waters from southeastern Cuba represents the firs Dolichospermum spiroides blooms in a man-made lake in Sarawak, Borneo pond in Serian, Sarawak, and co-existed with a Microcystis bloom. However, the species and cell density for both genera were not recorded [3]. This is the first documented report of D. spiroides in Sarawak waters. The occurrence An online platform (GEE App) for Trophic State Index monitoring of inland waters in Latin America Fig. 1. a) The dark gray region shows the Paraná River Basin in Brazil; b) Water masses within Paraná River Basin palette according to the Chl-a concentration average for 2020. The red rectangle indica Remote sensing of recurrent cyano HABs in Patos Lagoon, Brazil Fig. 1. Map of Patos Lagoon (southernmost part of Brazil) taken from [7]. Black circles indicate the four sites chosen forNDCI values retrieval [4]. Every austral summer, dense surface growth and accumulations of cyanobacteria threaten ation promoting the prevalence and duration of cyanoHABs. More detailed information will be published soon adding modeling tools to locate dominant cyanoHAB accumulation sites within the PL, and their potential exportation to the ocean. Future studies are needed to discriminate between local effects Blooms of Akashiwo sanguinea (Dinophyceae) in a tropical estuary in northeastern Brazil We report an inter-annual bloom of the unarmored dinoflagellate Akashiwo sanguinea in a pristine estuary (Figure 1F) in Brazil. The estuarine section of the Serinhaém River, Camamu Bay is a species-rich ecosystem can affect the entire structure of a community due to changes in composition due to outcomes of biotic interactions with one species being benefited while another one is harmed. The spatial location of SE10 within an area of potential disturbance driven by urban tributaries alters ecological stoichi Can artisan fishermen help to prevent HABs intoxication? A science communi cation project in Rio de Janeiro, Brazil Fig. 1. Geographic distribution of the main harmful microalgae genera in Brazilian coastal waters. These genera may induce different poisoning syndromes: amnesic shellfish poisoning ( Authors Raquel AF Neves, Júlia Torres, Nathália Rodrigues & Clarissa Naveira, Graduate Program in Neotropical Biodiversity (PPGBIO), Research Group in Experimental and Applied Aquatic Ecology, Federal University of the State of Rio de Janeiro (UNIRIO), Avenida Pasteur 458-307 Rio de Janeiro- RJ, CEP The VIII Workshop the Group HarmAlfonso Vidal (Colombia). Their of dediconsider it urgent to finalize The VIIIofWorkshop of the Group Harmful Algal Blooms the Caribbean (ANCA) of a regional ful AlgalIOCARIBE Blooms of (Intergovernmental the Caribbean catedOceanographic work contributedCommission sig Aotearoa/New Zealand Japan collaboration strengthened through HAB research at Cawthron Institute the 16th Young Researchers Award from the Japanese Society of Phycology for his research on harmful algae in Japan. Acknowledgements The collaboration between New Zealand and Japan has been continued ANNOUNCEMENT: The International Phytoplankton Intercalibration The International Phytoplankton Intercalibration (IPI) Proficiency Testing scheme in abundance and composition of marine microalgae programme 2021 is now open for registration for 2021 through www.iphyi.org. The schedule for 2021 and all The 19th International Conference on Harmful Algae 2021 (ICHA2021) is going virtual! We appreciate the responses that many of you provided in the recent survey which indicated that 85% of respondents will participate in a virtual meeting. The abstract submission deadline is 9 April 2021. Details on In memoriam Maria Esther Angélica Meave del Castillo (1960-2020) María Esther Meave (who also received the nickname Teté or Tey by many of her friends) was born in Mexico city, Mexico (September 5th, 1960) and passed away on December 6th, 2020, after contracting COVID-19. She earned her Master and Leif Bolding, graphic designer and webmaster at the Department of Biology, University of Copenhagen, Denmark, has been an unsung hero of Harmful Algae News. Working behind the scenes since 2000 as responsible for the layout of each issue. Leif retires at the end of April 2021. He will have plenty of