Mass mortality of marine invertebrates associated with the presence of yessotoxins in northern Chile Fig. 1. Map of the study area showing A) Chilean coast; B) Pabellón de Pica, Tarapacá Region C) Bahía Inglesa, Atacama Region; D) Puerto Aldea, Coquimbo Region During the austral summer of 2019, mass mortalities of marine invertebrates were detected at different locations throughout an extensive geographic area (up to 1000 km coastline) along the northern Chilean coast (Fig. 1). On January 24th, massive strandings of starfish (Stichaster striatus), red sea urchins (Loxechinus albus), and clams (Ameghinomya antiqua) were detected in Pabellón de Pica, Tarapacá Region (Fig. 2A, B). Unfortunately, accurate in- formation about the total stranded biomass of each species was not obtained. The estimated density of sea urchins was between 15 and 20 individuals m2. Toxin analyses of digestive tissue samples of the stranded specimens carried out by Liquid Chromatography- High Resolution Mass Spectrometry (LCHRMS) revealed the presence of yessotoxins (YTX) with concentrations ranging between 0.1 and 0.4 mg YTX kg-1 (Table 1). Two weeks later, on February 1011th, a mass mortality of Humboldt squid (Dosidicus gigas) was detected in Bahía Inglesa, Atacama Region (Fig. 2C, D). During this episode, thousands of dying or dead squid were washed ashore or appeared floating near the shore of one of the most visited beaches in northern Chile. At the end of this event, the density of beached squid on the sand was estimated to be between 45 and 50 individual m-2 (approximately 15 tons). The health risk posed by the contaminated dead animals led the Ministry of Health to carry out a social media campaign to prevent their consumption. In addition, the City Council organized the beaches to be cleaned, to mitigate the negative impact on tourism caused by the decaying animals. LC-HRMS analyses of pooled samples of the viscera from individuals collected on February 11th revealed the presence of YTX with a concentration of 0.42 mg YTX kg-1. By the end of summer, on March 31th, a new mass mortality event of squid D. gigas was detected at the artisanal fishing harbor of Puerto Aldea, Coquimbo (Fig. 2E, F). During this event which took place during the night and early morning, thousands of individuals were found dead or dying, mainly lying on the surface of harbor facilities and, to a lesser extent, on nearby beaches. A total of 130 tons of stranded biomass was quickly collected and sold by fishermen to fish processing plants and the local market. However, in order to guarantee seafood safety the health authorities demanded an analysis of the squid in all of the fishing plants involved and withdrawal of the squid being sold in the local market. LC-HRMS analyses of the viscera from pooled samples revealed the presence of YTX with a concentration of 0.12 mg YTX kg-1. Table 1. Concentration of yessotoxin detected in different marine invertebrate species during the mass mortality events detected along the northern Chilean coast. Date Species ͲͳȀʹͶȀͳͻ Stichasterstriatus ͲͳȀʹͶȀͳͻ Loxechinus albus ͲͳȀʹͶȀͳͻ Ameghinomya antiqua ͲʹȀͳͳȀͳͻ Dosidicus gigas 6 ͳȀͲȀͳͻ Dosidicus gigas Location Type of sample mg YTX kg -1 ͲǤͳͲ ͲǤͶͷ À ͲǤͳͳ ͲǤͶʹ ͲǤͳʹ HARMFUL ALGAE NEWS NO. 64 / 2020 Harmful Algae News An IOC Newsletter on Toxic Algae and Algal Blooms No. 64 - June 2020 www.ioc-unesco.org/hab The IOC Taxonomic Reference List of Harmful Microalgae The creation of the IOC Taxonomic Reference List of Harmful Microalgae was first discussed 23 years ago at the Fourth Session of the ever the information presented in publications is not always easy to interpret. Toxic blooms often contain several species and studies on individual species are therefore required to determine the species responsible for the toxin production. In addition, species are sometimes difficult to identify considered this to be identical to the previously described P. mexicanum [9]. This statement makes little sense, and Loeblich et al in fact do not mention P. mexicanum in their article. Faust [8] illustrated material which resembled P. rhathymum using the radical arrangement of some of the trichocys Massive salmon mortalities during a Chrysochromulina leadbeateri bloom in Northern Norway From mid May to mid June 2019, fish farmers along the coast of Nordland and Troms, northern Norway, experienced sudden mortalities of caged salmon [1] (Fig. 1). These mortalities were assumed to be due to a blo Fish kill in numbers [2] 13 000 ton fish 7.5 mill salmon 80 mill EUR 14 companies Fig. 2. Map of Norway showing the area where the Chrysochromulina leadbeateri bloom occurred causing massive fish kills in May-June 2019 References 1. Fiskeridirektoratet 2019. https:// www.fiskeridir.no/Akvakult Mass mortality of marine invertebrates associated with the presence of yessotoxins in northern Chile Fig. 1. Map of the study area showing A) Chilean coast; B) Pabellón de Pica, Tarapacá Region C) Bahía Inglesa, Atacama Region; D) Puerto Aldea, Coquimbo Region During the austral summer of 2019, ma research is needed to determine the mechanism of action and the toxin effects on tissues and cells of the main affected species. Finally, there is a need to establish an educational plan to protect the public and avoid the consumption and commercialization of potentially toxic marine invertebrates. First Report of Heterocapsa minima (Dinophyceae) from Aotearoa/ New Zealand Small planktonic armoured dinoflagellates within the genus Heterocapsa are currently represented by 20 species with some having a world-wide distribution [1-2]. Blooms of some Heterocapsa species have been associated with fi Fig. 2. Maximum likelihood (ML) molecular phylogenetic tree of Heterocapsa minima and H. steinii strains isolated from coastal areas of New Zealand based on the LSU rDNA D1/ D2 sequences (20 sequences, 700 positions). The alignment site corresponded to the 69768 bp site of a sequence from H. steinii Yellow-green tides could become a recurrent event along the Ligurian coast (Italy) Fig. 1. A) Sestri Levante and Baia del Silenzio bay, characterized by shallow water and mixed rocky-sandy seabed containing the macrophyte, Posidonia oceanica (dark grey) and carpet-like matte (light grey) habitat. B First report of a high biomass bloom of Peridinium quadridentatum (F. Stein) Gert Hansen from the tropical Cochin estuary SW coast of India Fig. 1. Map showing the area of P. quadridentatum bloom in Cochin estuary, southwest coast of India Peridinium quadridentatum (F. Stein) Gert Hansen is a cos Table 1. Physico-chemical parameters of P. quadridentatum bloom area in Cochin Estuary Parameters Water Temperature (oC) Salinity (psu) Dissolved Oxygen (ml L-1) Nitrate (μmol L-1) Silicate (μmol L-1) Phosphate (μmol L-1) Chlorophyll a (mg m-3) 28 20 2.01 10.6 23.3 1.3 27.5 higher turbidity, lowe Are mesophotic seamounts reservoirs for potentially toxic dinoflagellates associated with Ciguatera poisoning? A case study from the SW Indian ocean (expédition La Pérouse, 2019) Fig. 1. Location map of La Pérouse seamount off La Réunion. In the western Indian Ocean, a Ciguatera Fish Poisoning (CF Using Machine Learning to Observe Abundance Patterns of the Dino flagellate Noctiluca scintillans in the Western English Channel Noctiluca scintillans is a Harmful Algal Bloom (HAB) species with a wide geographic distribution. It frequently blooms and causes negative impacts on marine ecosystems [1] References 1. Sarma VVSS et al 2019. Mar Pollut Bull 138: 428-436 2. Faust MA & RA Gulledge 2002. Contributions for the US National Herbarium 42: 1-144 3. Graham MD et al 2018. Limnol Oceanogr-Meth 16: 669-679 Author Christian Bamber, The Marine Biological Association, Citadel Hill, Plymouth PL1 2PB International validation and recognition of method for paralytic shellfish toxins in bivalve molluscs Food safety scientists from Cefas (UK) and Cawthron Institute (New Zealand) have led an international study over the past four years to gain international recognition for a new method to quantify pa Aotearoa/New Zealands nationally significant Cawthron Institute Culture Collection of Microalgae (CICCM) The CICCM is critical to international research projects and the 500 isolates of microalgae and cyanobacteria in the collection have been sourced from oceans, lakes and rivers in New Zealand, the The 11th EASTHAB Symposium and 4th Philippine HAB Conference The 11th EASTHAB Symposium and 4th Philippine HAB Conference were held back-to-back from December 11 13, 2019 at the Microtel Hotel, Puerto Princesa, Palawan, the Philippines. The theme was Advances in Harmful Algal Bloom Research, Monito Fig. 1. Participants in the 11th EASTHAB Symposium/4th Philippine HAB Conference Fig. 2. Department of Science and Technology secretary Fortunato dela Peña with the keynote, plenary speakers and local organizing committee leads. Left to right: Dr. Ichiro Imai, representative of the Vice Mayor of Pu The ICES-IOC Working Group on Harmful Algal Bloom Dynamics 2020 Meeting The International Council for the Exploration of the Sea (ICES) and the Intergovernmental Oceanographic Commission of UNESCO (IOC) have collaborated closely for 26 years, stimulating research on HAB population dynamics and monit Fig. 2. Shared day between ICES-IOC WGHABD, ICES-IOC WGBOSV and ICES WGITMO ences using molecular methods as well as results from studies in Arctic areas. These studies presented data on HAB and invasive non-native species present in Arctic waters. A USA study focused on the distribution, community Typical benthic habitat with macroalgae and limestone rubble observed at ~ 60m depth on La Pérouse seamount, Indian Ocean (Photo courtesy of L. Ballesta). Eds-in-chief Beatriz Reguera, IEO, Vigo, Spain Eilen Bresnan, Marine Scotland, UK Regional Editors Caribbean: Ernesto Mancera jemancerap@unal.e