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 bloom of the haptophyte Chrysochromulina leadbeateri. Fish death was relatively sudden with gill damage frequently observed. Little or no changes were seen in the pathology of the internal organs. Around seven and a half million farmed salmon died valued at 800 million Norwegian kroner NOK (80 million €). This is the most extensive fish mortality event associated with a HAB recorded in Norway to date. The first reports of fish mortalities came from Astafjorden in Troms and Ofotfjorden in Nordland. The C. leadbeateri bloom then moved further north to Vestfjorden and Troms during the following weeks (Fig. 2). A maximum cell density of 45 x 106 cells L-1 was recorded. Chyrsochromulina leadbeateri, was reported to have caused fish-kills in the same area before. In the second half of May 1991, C. leadbeateri bloomed in Vestfjorden and surrounding areas [3,4]. The total loss then was 742 tons of salmon with an estimated value of 22.5 million NOK (3.5 mill US dollars), a substantial loss considering the size of the fish farming industry at the time. A smaller bloom of C. leadbeateri caused fish-kills in the same area in 2008. One of the first extensive fish kill events in Norway was caused by a bloom of Chrysochromulina polylepis (now Prymnesium polylepis) in 1988. That bloom occurred in Skagerrak and Kattegat along the coast of Norway, Sweden and Denmark in May and June. Both farmed and wild fish were killed as well as a wide range of benthic fauna. Since then more than 30 different species of Chrysochromulina have been recorded in Norwegian coastal waters, some new to science. A result of these events was the formation of the Norwegian algal monitoring program (www. imr.algeinfo.no). Questions remain as to why this alga bloomed again in this area, and why it became so toxic. It is still unknown which toxins are produced by C. leadbeateri and the conditions which promote toxicity. However, previous research on Prymnesium polylepis indicates that the toxicity increases during nitrogen-sufficient but phosphorus- limiting conditions. The toxicity may reduce grazing by protozoans and zooplankton, allowing rapid growth and bloom formation of these potentially toxic haptophytes [4]. To fully understand what caused these blooms and promoted toxicity of C. leadbeateri in 2019 more research is needed. Monoalgal strains of C. leadbeateri have been established at the University of Oslo from the blooms in 1991 and in 2019 and are currently being used in experiments to improve our knowledge on bloom drivers to implement mitigation practises for fish kills in the future [5] (Fig. 3). Fig. 1. Boxes of dead salmon are transported to the company Northern Lights Salmon land base in Sør-Troms. Photo Northern Light Salmon. 4 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