day, we still do not know if there are other factors at work perhaps a density-dependent or quorum-sensing type of response, or even a response to the presence of grazers or parasites. Exploration of this response has long been limited by the constraints associated with laboratory cultures, but now we are fortunate to be entering a new era of in situ investigations thanks to biosensors like the Imaging FlowCytobot (IFCB), that allow us to observe the encystment process underwater in the field with exFig. 3. Karen Steidinger, Penrose Conference on Fossil and Modern traordinary resoluDinoflagellates, 1978 tion. Among many rameters on the formation, deposition, other recent findings, IFCB observaand germination of cysts. One of several tions by Mike Brosnahan [11,12] have challenges at the time was that we were documented mass gametogenesis (75 unable to produce true hypnozygotic 90% of all cells) at the end of A. catenelresting cysts in our cultures. There was la blooms under conditions that do not good reason to believe that sexual- appear to be nutrient-limited. I believe ity was involved, so compatible mating that the tools are now in hand to retypes needed to be combined. Further, solve the longstanding mystery of what nutrient limitation seemed to be a trig- induces cyst formation in the field and ger to initiate the process. We quickly suspect that the final story will be much learned that dinoflagellate species var- more complicated than simple nutrient ied considerably in the ease with which limitation. they could be induced to form cysts in Not long after our early successes cultures. Species like Scrippsiella tro- with sexual induction and cultures, choidea produced prolific numbers my attention shifted to studies of cyst of cysts without special precautions, distribution and dynamics in the field. whereas our Alexandrium cultures were We were documenting the abundance far more recalcitrant. Eventually, with and dynamics of vegetative cells in the deliberate modifications to the content plankton during blooms, so I wanted to of the culture medium as well as the quantitatively link those observations manner in which it was prepared (i.e., to cyst abundance and distribution in minimizing contaminants and precipi- the sediments before and after those tates) we were finally able to produce blooms. At the time, however, studies cysts in Alexandrium cultures [10], of dinoflagellate cysts were still heavily opening yet another door to new stud- influenced by geologists working with ies and discoveries. sediment cores. Typically, those invesIt is clear that nutrient limitation tigations enumerate cysts at different can induce sexuality and cyst forma- depths in cores, expressing results in tion in cultures of A. catenella and terms of cysts per gram of dry sediment. other dinoflagellate species, but to this Although this approach is appropri6 ate when one is studying vertical profiles of dead, empty, or fossilized cysts in sediments dating back hundreds or thousands of years, this type of parameterization is not useful for biological studies in which one wants to map out the distribution and abundance of cysts and estimate the number of germinated cells inoculating the overlying water column. To address the latter topic, we needed to know how many cysts were present per square meter of sediment, so we started doing experiments to see how reproducibly we could quantify cysts per cubic centimeter or ml of sediment. Our results were consistent and scientifically appealing so we published the method [13] and began to use it in the salt ponds and other nearshore locations. This approach was not well received, however, as I was repeatedly criticized at conferences when these results were presented. Geologists argued that the water content and lithology of surface sediments differs sufficiently from site to site, or from layer to layer, and that normalization of cyst abundance to a volume of sediment introduces substantial errors compared to the dry weight approach. I remember being told at an international conference that my results and the population dynamics models based on them were essentially meaningless! This disagreement went even further, as one publication [14] recommended that future studies use standardized methods based on measurements of cyst concentrations per gram of dry sediment. This recommendation was repeated in training manuals for those working with living dinoflagellate cysts [15]. Despite this strong and vocal opposition, I was still firmly convinced that cysts could be quantified per unit volume of sediment, and so I initiated a study over multiple years in which we quantified cysts both ways (i.e., cysts per gram dry weight and cysts per ml). We did this in the Gulf of Maine across a wide range of sediment types and cyst concentrations, and found a strong and statistically significant relationship between the two parameters, for the top cm of sediment (Fig. 5). The relationship for the top three cm of sediment is even stronger. This of course does not mean that this relationship will apply in every location, but it does show that the hypothetical concerns raised about this HARMFUL ALGAE NEWS NO. 59 / 2018 Harmful Algae News An IOC Newsletter on Toxic Algae and Algal Blooms No. 59 - February 2018 www.ioc-unesco.org/hab Content 25 years of HAN and IPHAB...... 1 25 YEARS Harmful Algae News was first published in early 1992 in response to requests from the participants at a number of IOC meetings and pacted by harmful algal events. Since Harmful Algae News turned 20 years old in 2012, it has been a web based e-newsletter which meant longer issues were possible and back issues easily accessible. We are currently working on a searchable index for all Harmful Algae News issues. The start of Harmful Intergovernmental Panel on Harmful Algal Blooms also turned 25! During 1992, the same Year as the IOC published the first issue of Harmful Algal News, it also established an Intergovernmental Panel on Harmful Algal Blooms (IPHAB) which has met every second year since it was formed. The Panel is com A retrospective look at the early days of HAB cyst research, and a look to the future On this occasion of the 25th anniversary of the publication of Harmful Algae News, several of us were asked to look backwards in time to some of the earlier days of HAB science. One area of study that has been a ma dormant stages and that these stages might be associated with certain bottom sediments. This then brings up the question, if benthic resting stages of certain dinoflagellates actually seed coastal red tides, are there localized areas of accumulation, or what we could call seedbeds?..........The poss day, we still do not know if there are other factors at work perhaps a density-dependent or quorum-sensing type of response, or even a response to the presence of grazers or parasites. Exploration of this response has long been limited by the constraints associated with laboratory cultures, but now approach did not stand up to data at my study locations. I raise this issue in this narrative because I want to correct what I feel are unjustified recommendations that may prevent those working on cysts from obtaining the type of biological data that can advance our understanding of certain types o number of cysts in subsurface layers unable to germinate or emerge, presumably due to lack of oxygen or to the tortuous pathway posed by sediment grains and detritus. Many might think that major storms and waves can erode significant layers of sediment and transport cysts long distances, but here ag How do algal blooms kill finfish and how can we mitigate their impacts? Algal blooms, water discolorations and their association with fish kills have been recorded since historic times, such as the description in the Bible (1000 years BC) all the waters that were in the river were turned to blood. A Table. 1. Economic losses from algal blooms for finfish aquaculture in different parts of the world HAB species Chattonella Heterosigma Cochlodinium polykrikoides Heterosigma Chaetoceros Heterosigma Karenia digitata Karenia mikimotoi Country Financial Losses Japan Korea, China Canada British Col emergency harvest operations. To prevent the buildup of histamines, fish should be kept alive as long as possible during harvesting. This can be achieved by diluting algal concentrations via airlift upwelling, or by targeted in-pen emergency application of clays [23] that mop up ichthyotoxins at cla As part of the 25th anniversary issue of Harmful Algal News I am providing an overview of the IOC-UNESCO Taxonomic Reference List of Harmful Algae (www. marinespecies.org/hab/) and will highlight some of the problems which have faced or are facing the Intergovernmental Panel on Harmful Algal Blooms Dinophyceae the authors intended the new genus to be described according to the botanical nomenclature. The lack of a Latin diagnosis therefore made it invalid. The confusion has actually still not been resolved, and the problem needs to be discussed and decided upon by the International Nomenclatur geographically widespread species being able to form fertile offspring, while other populations of the same species are not. Molecular techniques have contributed very significantly to solving many taxonomic problems, but they have not resulted in the emergence of a finite species concept. We have t Algal toxin discovery, management and regulation over the last 25 years Algal toxins in the dark ages (pre-1992) From a historic perspective, knowledge about algal toxins can be divided into truly prehistoric occurrences such as known from paleontological studies [1-2] and more recent historic recor lar rapid increase in known analogues has been observed for the azaspiracid (AZA) group, with the first analogue described in 1998 [64] and a review in 2014 reporting 30 analogues [65]. Only three years later, over 50 analogues are known for this group, including novel phosphate derivatives [66-71]. Butterflies in Brazil Abstracts are not always reliable guides to authors intentions. They are not expected to reveal a great deal about the evidence to be deployed in support of the science, evidence that may not even exist before deadlines for writing abstracts! Nevertheless, as examples of a mino on a decadal time scale, and identified palaeoclimatic oscillations are not necessarily a useful guide to its interpretation. An obvious obstacle to detecting climate signals in HAB data is posed by anthropogenic eutrophication. Another obstacle is the fact that phytoplankton respond directly to the trends, Karenia brevis might appear more often in the South Atlantic Bight of the US and Gymnodinium catenatum bloom more often in northwestern Iberian waters. There was also a warning by Barrie Dale germane to such speculations, that large scale climate models cannot predict local changes. Little m Red tides in Kamchatka coastal waters (Bering Sea, Russia) are a barrier for the salmon fishery and Pacific salmon Fig. 1. Map of Olyutorskiy Bay (Kamchatka, Bering Sea) where a red tide, reported by fishermen, occurred in July 2017. The stars denote fishery sites: red, affected by the bloom; green Fig. 2. Red tide in Olyutorskiy Bay on 15th July 2017 grounds of the Olyutorskiy Bay river basin performed during the second half of August showed an atypical distribution in the rivers. Maximal escapes were recorded in river basins located in the western and eastern parts of the Olyutorskiy Bay ar First report of Gambierdiscus in the Western Mediterranean Sea (Balearic Islands) Gambierdiscus (Dinophyceae) species are benthic dinoflagellates living in marine littoral zones of circumtropical areas and have recently been described in temperate waters [1]. Some species are producers of potent neu the SEASENSING (BIO2014-56024C2-2-R) project and the CERCA Programme/Generalitat de Catalunya. A. Tudó and A. Toldrà acknowledge IRTAURV-Banco Santander for their respective PhD grants (2016 PMF-PIPF-74 and 2015PMF-PIPF-67). The authors are grateful to Vanessa Castan and José Luis Costa for sampling Comparison by light microscopy and qPCR of potentially ichthyotoxic microalgae in Danish on-shore lagoons producing European flounder (Platichthys flesus): Pros and cons of microscopical and molecular methods Fig. 1. Lagoon used for production of European flounder at Fishlab, Denmark. Evaluation o Fig. 2. Comparison of phytoplankton species identification and cell densities (cells L-1) by qPCR (A and C) and light microscopy (target species and groups which potentially could comprise ichthyotoxic organisms) (B and D) in lagoon 1 (A and B) and lagoon 6 (C and D), respectively. The right Y-axis present in a sample then qPCR would miss those probably due to lack of a developed assay. However, LM does require high levels of taxonomic skills and the precision in identification is only as accurate as the taxonomist allows. Different taxonomists trained in different ways using different identif As qPCR measures genetic material rather than viable cells an over estimation of cell numbers can occur due to the inclusion of dead or dying cells. Problems may also occur when targeting multiple copy genes where the organism carries different numbers of the target depending on nutritional status, The Cawthron Institute Culture Collection of Micro-algae (CICCM) The CICCM is designated as a nationally significant database by the New Zealand government and so receives partial funding for its continued existence. Isolates from 13 classes of micro-algae are maintained either as live cultures or c The XVIII International Conference on Harmful Algae is approaching! It is time for nominations for achievement awards (Yasumoto Life Time and Patrick Gentien Young Scientist), registration to the conference as a student if you wish to participate in the Maureen Keller Award competition and fundraisi Forthcoming Events First announcement of the 11th International Conference on Toxic Cyanobacteria (ICTC) We are pleased to disseminate the first announcement of the 11th International Conference on Toxic Cyanobacteria (ICTC) that will be held in Krakow, Poland from May 5 10, 2019. The ICTC is a per International Coordination of Research on Harmful Algal Blooms From GEOHAB to GlobalHAB International cooperation is fundamental to advance understanding of HAB dynamics and to improve our ability to predict them. Fostering this international cooperation was the mission of GEOHAB (Global Ecology and 18th International Conference on Harmful Algae www.icha2018.com IMPORTANT DEADLINES Abstract submission deadline: 15 April 2018 Early bird registration: 15 July 2018 Get the 17 ICHA Proceedings at www.issha.org Eds-in-chief Beatriz Reguera, IEO, Vigo, Spain Eilen Bresnan, MARLAB, Scotland, UK Regi