Search

15th International Congress of Protistology, International Society of Preotistologists (ISOP), 30 July - 4 August 2017 , Prague, Czech Republic, The oceans are populated by a multitude of microbes, both eukaryotes and prokaryotes, but our knowledge of their ecological interactions is still limited. To help shed light on important long-term interactions we have constructed microbial association networks from marine plankton samples taken every month for 10-years in the North-Western Mediterranean (Blanes Bay Microbial Observatory). From the 120 samples we sequenced 18S and 16S rDNA amplicons from two different size fractions (pico-plankton [0.2-3mm] and nano-plankton [3-20mm]) and recorded 18 environmental variables. We calculated positive and negative correlations between Operational Taxonomic Units (OTUs) from the amplicons with eLSA (extended Local Similarity Analysis). The association network from OTUs present in at least 10% of the samples (2826 eukaryotes and 2856 bacteria) was highly connected with 2 947 606 significant edges (p

15th Symposium on Aquatic Microbial Ecology (SAME15), 3-8 September 2017, Zagreb, Croatia, Protists are recognized as fundamental components of marine ecosystems, contributing to phytoplankton biomass, primary production and food-web interactions. However, their long-term dynamics are poorly understood and, in particular, we know little on how predictable is the assembly and disassembly of their communities in temperate zones featuring annual climate cycles. Here, we analysed a long-term time-series in order to determine the patterns of community dynamics in a model protist assemblage. We carried out a monthly sampling of the picoplankton (0.2-3 µm) and nanoplankton (3-20 µm) during 10 years in the Blanes Bay Microbial Observatory (coastal North Western Mediterranean). The taxonomic composition of both assemblages was determined by Illumina sequencing the V4 region of the 18S rDNA gene. We found that the community showed two recurrent states, corresponding to summer and winter months, and two transition states corresponding to spring and autumn, being the winter communities more similar through the different years. Furthermore, we designed a `Seasonality Index¿ that allowed us to identify the seasonal taxa and quantify the strength of their seasonality. We identified that 13.2% of the OTUs (39.3% abundance) and 20.6% of the taxonomic Classes (35.2% abundance) showed seasonality and among them we could differentiate two clear behaviors (wave or pulse). Finally, we also identified seasonality in permanently rare taxa. In summary, the analysed protist community showed a recurrent annual pattern generated by their seasonal abundant members. Furthermore we identified multiple behaviors (common-rare, seasonal-no seasonal, wave-pulse) within the assemblage

Association for the Sciences of Limnology and Oceanography (ASLO) Aquatic Sciences Meeting, Mountains of the Sea, 26 February - 3 March 2017, Honolulu, Hawai`i, Nearshore shallow waters (i.e. < 2 km from the coast and < 20 m depth) represent a transitional area between land and open ocean where key marine ecological processes occur. During summer, when oligotrophic conditions prevail offshore in the Mediterranean Sea, an alongshore zone with enhanced phytoplankton biomass is often evidenced in these waters. Here, using continuous underway measurements as well as discrete samples, we describe the cross-shore environmental typology and the associated microbial planktonic communities of these waters. Cross-shore temperature, salinity and fluorescence transects obtained from coast to offshore reveal widespread presence of modified water bands generated by nearshore temperature warming and diffuse groundwater discharges in the Mediterranean Sea. Intense phytoplankton biomass buildup was associated with these modified waters (up to 50 fold offshore chlorophyll). We show that the physical and chemical characteristics of this nearshore stripe dramatically vary at scales of hours following a diurnal cycle that is regulated by heating and wind forcing. Plankton communities characterized by increased microplankton and bacterioplankton populations are able to actively exploit these nearshore conditions, constituting an independent and distinct assemblage from that prevailing further offshore. Our study argues the relevance of the formation of a nearshore niche and its temporal stability for the development of a distinct microbial community which could eventually favor the emergence of harmful algal blooms

17th International Conference on Harmful Algae (ICHA), 9-14 October 2016, Florianópolis, Santa Catarina, Brazil.-- 1 page, The genus Parvilucifera (Perkinsozoa, Alveolata) comprises parasitoid species that infect dinoflagellates. However, they are scarcely reported and little is known about their diversity, distribution, habitat and host range. Such aspects have been explored in this study either at the regional scale of Spain and at global scale. At regional scale, we commonly reported them during harmful algal bloom events, infecting toxic or bloom-forming dinoflagellates like Alexandrium minutum, Dinophysis sacculus, Barrufeta bravensis, Prorocentrum micans or Durinskia baltica. These parasitoids seem to be well-adapted to the ecology of their blooming hosts given that the high reproduction rate of Parvilucifera and their density-dependent transmission allow a rapid increase of the parasitoid population during the outbreaks of its hosts. Several species of Parvilucifera were recurrently detected, sometimes coexisting at the same location, and clearly some of them represent new diversity yet to be described. At global scale, most of the diversity of Perkinsozoa in marine waters worldwide is only represented by unidentified environmental sequences. During recent years, extensive studies have been conducted to explore the diversity of marine protists using high-throughput sequencing techniques, including circumnavigation cruises (BioMarks, Ocean Sampling Day, Malaspina, Tara). We have used some available datasets to study the presence of the different species of Parvilucifera. The results obtained suggest a global distribution of Parvilucifera and its preference for coastal and shallow environments, in agreement with its infection strategy

Sampedro, Nagore ... et al.-- 17th International Conference on Harmful Algae (ICHA), 9-14 October 2016, Florianópolis, Santa Catarina, Brazil.-- 1 page, There are evidences that HABs are increasing worldwide due to human causes, such as eutrophication and an increase in confined waters. In addition, it is also likely that climate variations can affect HABs dynamics. To understand future perspectives of coastal harmful events, we need to identify the underlying factors contributing to the current variations. Using a phytoplankton time series collected at 16 confined NW Mediterranean Sea locations, we investigated the long-term trends of two local PSP-toxin-producing species, Alexandrium minutum and A. pacificum, and their responses to different environmental drivers. These two species responded differently to the same environmental conditions along the Catalan coast (NE Spain). From 2000 to 2012, blooms of A. minutum in Catalan harbors doubled in their frequency whereas those of A. pacificum decreased slightly. In the 1990s, the first detection of the toxic bloom-forming A. pacificum in several localities of the NW Mediterranean coast suggested the expansion of this species. Our results show that, after the initial period of expansion, the abundance of A. pacificum declined such that by 2008 the species was no longer found in most sampling locations. The potential contributions of regional and local factors in this decrease in A. pacificum abundance are considered. For example, the colder water temperatures in 2004¿2005 coincided with a reduction in A. pacificum abundances in most of the monitored stations. The possible link between these two events is assessed by analyzing data from a wider geographic area, including other NW Mediterranean locations in Sardinia and southern France

DEVOTES Final Conference : Marine Biodiversity, the key to healthy and productive seas, 17-19 October 2016, Brussels

2nd Plankton Chytridiomycosis Workshop, 15-17 September 2016, Skagaströnd, Iceland

IX Congreso Ibérico sobre Gestión y Planificación del Agua, Agua, ciudad y salud de los ecosistemas: Integrando perspectivas, proponiendo soluciones, celebrado del 7 al 9 de septiembre 2016 en Valencia.-- 1 page, Los océanos tienen un ciclo de fertilidad propio alimentado por el ascenso de las aguas profundas ricas en nutrientes. En las zonas costeras hay además procesos de fertilización alimentados por los aportes continentales. Sin ambos procesos la vida en los mares seria escasa. Los flujos de aguas continentales enriquecen las aguas litorales y les conÞ eren una dinámica propia distinta del resto del océano. Las comunidades vivientes costeras, situadas en la frontera entre un continente que aporta y un mar que diluye, responden estructural y funcionalmente al balance de flujos. El hombre modiÞ ca profundamente los flujos continente-océano y en consecuencia las comunidades vivien-tes litorales. Este proceso empezó con la historia de la humanidad, se intensiÞ có con el incremento de la agricultura y la ganadería, cambió de escala con la industrialización y se convirtió en dominante y universal a lo largo del siglo XX. Hacer un balance de la situación actual, tomando la costa Mediterránea como ejemplo, nos ayuda a ver quién o qué gobierna el estado de las aguas costeras y en qué medida participa el hombre. Nos lleva también a reflexionar sobre el concepto de buen estado ambiental, su percepción social y su deÞ nición legal a través de las directivas ambientales europeas

European Molecular Biology Organization (EMBO) Symposia, A New Age of Discovery for Aquatic Microeukaryotes, 6-29 January 2016, Heidelberg, Germany

V Simposio Internacional de Ciencias del Mar, 20-22 July 2016, Alicante.-- 2 pages, During summer, when oligotrophic conditions prevail offshore in the Mediterranean Seea, an alongshore zone with enhanced phytoplankton biomass is ofteen evidenced in these waters. Here, using high continuous measurements of temperature, salinity and fluorrescence as well as discrete samples and primary production experiments, we examine the cross-shore typology and the associated chemical and biological characteristics of these waters. Data from three coastal regions in the NW Mediterranean revealed widespread presence of lower water density bands in the proximity of the shoreline generated by increased warming and groundwater seeps through the coastal sediments. Most often, enhanced phytoplankton biomass (max=9.6 mg Chla m3; up to 16 fold offshore chlorophyll) was associated with these modified waters and exponentially decayed in the offshore direction. Gradient characteristics are highly variable but the main onshore-offshore features, determined by terrestrial loads and hydrodynamics are locally consistent. Important variations were observed in the structure of the communities among nearshore sites which were attributed to variations in the geochemical conditions. Our study argues the relevance of the formation of a groundwater-sustained nearshore niche and its temporal stability for the development of a distinct community which could eventually favor the emergence of harmful algal blooms, This work was financed by the MINECO grant GRADIENTS (CTM2012-39476--C02)

Workshop Plankton Resting Stages: ecological, evolutionary and geological perspectives, 5-8 October 2015, Hanko Peninsula, Finland, Planktonic microalgae inhabit freshwater, brackish water and seawater environments and play a key role as phototrophs in the aquatic systems. The life cycles of most microalgal species are complex, with stages characterized by radically different morphologies and highly diverse environmental interactions. The two most common life stages are planktonic vegetative cells and benthic resting forms such as cysts or spores. During the planktonic stage, growth typically occurs in the water column, but for many species this is an ephemeral one. By contrast, resting stages remain dormant in sediments, where they are able to withstand adverse conditions until internal biological requirements and environmental conditions favour re-establishment of the vegetative form. However, despite the well-appreciated relevance of the different life-cycle strategies of microalgae with respect to their population dynamics, the full life cycle has been determined in only a few cases and for most species little is known about benthic resting forms and their interactions with the environment. Likewise, the factors that trigger transitions between the different life stages have yet to be identified. Here, we review current knowledge on the life-cycle strategies of major groups of microalgae and present an overview of the significance of life-cycle characteristics for algal bloom dynamics

VII European Congress of Protistology (ECP) in partnership with The International Society of Protistologists (ISOP), 5-10 September 2015, Sevilla, Spain

55 Conference Estuarine Coastal Sciences Association (ECSA 55), Unbounded boundaries and shifting baselines: Estuaries and coastal seas in a rapidly changing world, 6-9 September 2015, London, The DPSIR (drivers-pressures-state-impact-responses) framework is used to analyze the causal relationships between environmental and human systems and to report on environmental issues. The effective use of the DPSIR approach requires the accurate assessment of pressures. For coastal waters, although several methods have been evaluated, most of them are complicated or require large amounts of data. Here we present a novel method, the Land Uses Simplified Index (LUSI). The rationale of LUSI is based on the following assumptions: 1) Coastal waters receive pressures mainly from continental fluxes. 2) Coastal land uses determine the amount and nutrient richness of continental fluxes. 3) An area of riverine input into coastal waters is influenced by the complete range of uses of the respective watershed. 4) Coastal morphology has an effect on coastal water confinement and thus on received pressures. The LUSI algorithm combines categorized information on land uses (urban, industrial, agricultural, and riverine) that influence coastal waters and on the morphology of that land in terms of its ability to enhance or diminish these influences. A low LUSI value indicates that the coastal water area is not or only slightly influenced by continental pressures whereas a high LUSI value indicates a strong influence of continental pressures. Among the many advantages of LUSI are that it is easy to use, fast, cost-effective, repeatable, and yields comparable results among coastal areas. These characteristics recommend the use of LUSI within the DPSIR framework and in the implementation of environmental policies at the European level. For example, in accordance with the Water Framework Directive (2000/60/EC), LUSI (calculated using CORINE land cover) was able to demonstrate pressure-impact relationship for phytoplankton in Catalan coastal waters, NW Mediterranean (chlorophyll-atransformed=0.109*LUSI+0.208; R2=0.608; p=8.18e-05). These aspects of LUSI as well as the challenges in designing methodologies that balance simplicity with accuracy are discussed herein

1st Plankton Chytridiomycosis Workshop, 19-24 July 2015, Berlin

Aquatic Sciences Meeting, Aquatic Sciences: Global And Regional Perspectives - North Meets South, 22-27 February 2015, Granada, Spain, Here, we explore the usefulness of high-throughput sequencing technologies (HTS) as a tool for marine biodiversity monitoring and assessment of ecosystem health status. Whereas 454-pyrosequencing of 16S and 18S rRNA gene amplicons (454tags) has widely been used, only few studies have used Illumina (itags) and HTS cross-platform studies are rare. We have performed a comparison of the performance of 454tags and itags on a set of samples collected in the NW Mediterranean to determine bacterio- and picoplankton biodiversity. Preliminary results show that, due to the increase in the length of sequence reads, itags offer similar classification efficiencies than 454tags at a much lower cost, being therefore a cost efficient approach for marine biodiversity monitoring. We have also explored the concept of ‘indicator species’ and tested it in our samples, which include data from highly human-impacted beach areas to the open ocean. Our results show that certain taxa (i.e. some Gammaproteobacteria or the SAR11 clade) as well as the ratio between some phylogenetic groups (i.e. Gammaproteobacteria/Alphaproteobacteria) may be good indicators of ecosystem health status

Barattini, Paolo ... et .al.-- 6th International Workshop on Marine Technology - MARTECH 2015, 15-17 September 2015, Cartagena (Spain).-- 4 pages, 2 figures, The MARIABOX “MARIne environmental in situ Assessment and monitoring tool Box” is an autonomous marine monitoring device for man made and natural pollutants under development in the frame of a project funded by the European Commission (Contract 614088). The device it is conceived for installation on free floating devices, buoys, ships, or to be used as a portable instrument. It will work fully autonomously, collecting the marine water sample, analysing it, storing the data and transmitting them via satellite link. The main, high-level user requirements for the MARIABOX system are for analytical sensitivity below the thresholds for pollutants set by the European Commission, so to enable early warning, to be portable and capable of repeating measurements over at least six months without any servicing so to diminish the costs of logistics when deployed at sea

VII European Congress of Protistology (ECP) in partnership with The International Society of Protistologists (ISOP), 5-10 September 2015, Sevilla, Spain

55 Conference Estuarine Coastal Sciences Association (ECSA 55), Unbounded boundaries and shifting baselines: Estuaries and coastal seas in a rapidly changing world, 6-9 September 2015, London, The innershelf is a transitional, highly variable and productive area being also relevant for the physical, chemical, and biological processes and the transport of nutrients, plankton, and sediment offshore. This region contains well differentiated ecosystems spatially structured as cross-shore gradients. In low energy environments such as many Mediterranean coastal areas, phytoplankton biomass is frequently enhanced in nearshore waters, occasionally giving rise to intense blooms. Here, we characterize the fine scale variability of different nearshore coastal areas in the NW Mediterranean Sea during the stratified season. Data from 54 continuous high resolution cross-shore transects extending up to 3 km form the shoreline was used to investigate changes in biomass trends and its variability. Most of the sampled profiles displayed a differentiated nearshore environment consisting on changes on T, S and fluorescence as well as in their spatial scales of variation. These changes are accompanied by marked cross-shore differences in the composition of plankton communities (from micro to picoplankton). Variations in the nearshore gradients often respond to changes in the natural and anthropogenic forcings that regulate the ecosystem at each time and to the structure of the plankton assemblage. The heterogeneous nature of this nearshore ecosystem has profound repercussion on coastal ecosystem assessment and management

Aquatic Sciences Meeting, Aquatic Sciences: Global And Regional Perspectives - North Meets South, 22-27 February 2015, Granada, Spain, Even though much progress has been made recently in modeling planktonic communities, uncertainties remain large due to the countless types of planktonic species and the many interacting processes at work. Model formulations, including competition within and among trophic compartments, are often based on empirical relationships, which imply an excessive degree of parameterization and restrictive assumptions. We introduce adaptive modeling as an extension of data assimilation to the selection of model structures. Based on misfits between model predictions and observed data, adaptive modeling identifies model structures that need to be improved, estimates those improvements, and corrects the model accordingly. The model changes and learns from data providing more realistic predictions and selecting the most adequate model formulations that describe the system. We present an application of this new methodology aimed to identify the inter- and intra-specific competition processes that determine the population dynamics of a phytoplankton species (Alexandrium minutum) in a semi-enclosed site and the effects on bloom development

Teixeira, Heliana ... et. al.-- International Council for the Exploration of the Sea (ICES) Annual Science Conference, 21-25 September 2015, Copenhagen, Denmark.-- 2 pages, 1 figure, A Catalogue of Biodiversity Indicators useful for the implementation of the Marine Strategy Framework Directive (MSFD) was developed by the DEVOTES FP7 Project with the aim of providing the basis for assessing the environmental status of European seas. It is available online through the DEVOTool 0.64 software application that allows navigating a database of indicators related to the following MSFD descriptors: biological biodiversity, non-indigenous species, food webs, and seafloor integrity. The catalogue (v.6) contains over 500 indicators used by different initiatives, in national and international contexts. A comprehensive overview of these indicators is given: descriptions, data requirements, developmental status, geographical coverage and applicable habitats, biodiversity components and descriptors targeted, and related human pressures. The DEVOTool provides a query and analysis function for browsing the metadata, extracting and ranking lists of indicators best fulfilling pre-set criteria; enabling users to search, for example, for indicators suitable to fill in an identified gap or address a particular pressure in a marine area. The major strengths and gaps of the indicator set (at EU level) allow to focus the development of new indicators where it is most urgently needed, and to foster transfer of know-how across marine regions.

Aquatic Sciences Meeting, Aquatic Sciences: Global And Regional Perspectives - North Meets South, 22-27 February 2015, Granada, Spain, In marine food webs, microbial interactions involving eukaryotes and their parasites play an important role in controlling population dynamics. These interactions may alter the growth and mortality rates of a particular host and thus of its parasites, with consequences for the microbial community composition. Host-parasite interaction has been explored in Parvilucifera sinerae, which infects a wide range of dinoflagellates, including toxic-bloom-forming species. To define the biological parameters of one P. sinerae strain infecting Alexandrium minutum, A. catenella, Scrippsiella trochoidea, Protoceratium reticulatum, Heterocapsa niei and Gymnodinium catenatum, we examined (i) the influence of inoculum size on parasite prevalence,(ii) parasite generation time and (iii) parasite host preference in a mixed culture containing the above-mentioned species. In the artificial community, P. sinerae showed a clear preference to infect A. minutum and S. trochoidea, which is supported by the high prevalence of P. sinerae in these species, in comparison to those showed in G. catenatum and H. niei. Thus, although P. sinerae is considered to be a generalist parasite, our results are the first to show its preferential infection of certain dinoflagellate host species

55 Conference Estuarine Coastal Sciences Association (ECSA 55), Unbounded boundaries and shifting baselines: Estuaries and coastal seas in a rapidly changing world, 6-9 September 2015, London, In what degree nearshore plankton communities constitute an independent and distinct assemblage from shelf assemblages is a challenging question. Obvious physical and chemical differences exist among both systems but, also, important exchange and interdependencies are depicted by physical forcing. Clues to answer this question can be inferred by analyzing the degree of similarity between both systems and their respective biological communities. We analyze similarities between samples collected in nearshore and shelf waters in Palma Bay during a sampling period extending from April to September 2014. Strong differences between plankton structure at both sites are interpreted on the basis of physical and chemical variations at each site and on the degree of exchange induced by coastal currents and thermocline erosion

Póster presentado en la 16th International Conference on Harmful Algae ICHA, celebrada del 27 al 31 de octubre de 2014 en Wellington (Nueva Zelanda), Blooms of the toxic dinoflagellate Alexandrium catenella (temperate Asian clade) develop every year in two coastal environments in the NW Mediterranean Sea: Tarragona harbour and Thau lagoon. Using an 11-year data series (2000¿2010) from these localities, we studied the annual pattern, seasonal variability and trends in A. catenella cell abundance. Samples from Thau (2000¿2010) were re-examined with the calcofluor technique, revealing that A. catenella, not A. tamerense, is the species that produce annual recurrent blooms in Thau. We also studied the seasonal variability in relationship with biological, physico-chemical and meteorological variables occurring during the bloom events at the two sites. The occurrence of rhythms in the two A. catenella time series was investigated by Fourier spectral analyses, which showed two different frequency patterns. In addition to the annual periodicity, the spectrogram showed a periodicity of 4 months in Tarragona, and 6 months in Thau. None of the frequency patterns at either site showed periods longer than 1 year. There were no relevant trends in A. catenella cell abundances in both stations. The seasonality of A. catenella differed at the two sites, although both were subject to two temporally distinct blooming periods per year. Inorganic nutrients at both sites were clearly different, suggesting that blooms are not related to conventional nutrients. A common feature is the need of periods of calm wind required for bloom development at both sites. Wind stress previous to bloom developement is not required in Tarragona harbour in contrast to Thau lagoon. All together indicates that local factors are the main drivers of the different A. catenella seasonality at both locations

The 16th International Conference on Harmful Algae (ICHA 2014 New Zealand), Advancement Through Shared Science, 27-31 October 2014, Wellington, New Zealand.-- 1 page, Parvilucifera sinerae is a parasitoid that infects dinoflagellates, including harmful algal bloom (HAB) species. Here we describe the P. sinerae life cycle, in which a free-living zoospore penetrates a host cell and then develops a trophocyte while destroying the host cytoplasm. The trophocyte undergoes schizogony to form hundreds of new zoospores inside a sporangium. This sporangium remains dormant until, in response to an activation signal, the zoospores are released into the marine environment, where they are able to infect a new host. We identified dimethylsulfide (DMS) as the chemical signal involved in zoospore activation. Since many marine microalgal species are DMS producers, P. sinerae may be activated by many species. This fact is consistent with the results obtained in a previous study, where we found that P. sinerae is a generalist parasitoid, based on its broad host range among dinoflagellate species. Laboratory experiments demonstrated a prevalence of P. sinerae over 80% of the dinoflagellate population, causing the complete extermination of the host population after two parasitoid generations. The exploitation of dinoflagellate parasites in HAB mitigation has been proposed by several authors. However, as in many parasitic systems, the dynamics of P. sinerae infection are host-density-dependent, such that laboratory experiments poorly reproduce host-parasite interactions in nature, and field studies are lacking. In this work, we also present preliminary results of the prevalence of P. sinerae during a winter bloom of A. minutum in Arenys de Mar harbor (NW Mediterranean Sea) and discuss the parasite's potential contribution to bloom termination

Nagai, Satoshi ... et. al.-- The 16th International Conference on Harmful Algae (ICHA 2014 New Zealand), Advancement Through Shared Science, 27-31 October 2014, Wellington, New Zealand.-- 1 page, The distribution of Alexandrium catenella has been increasingly documented worldwide during the last decades. To examine the genetic relatedness of global populations, we conducted a genetic study using 2 haplotype markers and 7 microsatellite markers. Seawaters or sediment samples were collected from 11 different localities (17 samples) along 10 Japanese, 3 Chinese, 2 Mediterranean Sea, 2 New Zealand coastal waters and 839 clonal strains (temperate Asian clade) were analysed. One of the two haplotype markers showed high resolution to discriminate the difference of the geological origin in the populations. We could obtain the sequences from 673 clonal isolates. Two haplotypes were predominant of 85 haplotypes. The first one “Haplo01” (n = 316 isolates) and the second one “Haplo02” (n = 122) were predominated by Japanese isolates and Chinese isolates, respectively. Some Japanese isolates also belonged to haplo2. Interestingly, the Sea of Japan population had unique and highly diversified haplotypes derived from haplo2. New Zealand populations were mainly divided into three groups, i.e. the first one belonged to Haplo2, the second one derived from Haplo1, and the third one positioned in the middle of Haplo1 and Haplo2 groups. The half of Mediterranean Sea isolates belonged to Haplo1 and other half isolates had unique haplotypes derived from Haplo2. Microsatellite analysis data showed the significant population differentiation among most of the pairwise populations except for several Japanese pairwise populations. Results of the haplotype analysis well supported those at microsatellites analyses

Global Ecology and Oceanography of Harmful Algal Blooms (GEOHAB) Synthesis Open Science Meeting, 24-26 April 2013, Paris, France, Since the establishment of GEOHAB, our knowledge of harmful algal blooms has evolved. However, while general concepts and paradigms continue to guide our investigations they often fail to consider the multifaceted aspects of blooms and the producing organisms, especially the complexities of the biological traits of several congeneric species. Precise characterizations and more focused research efforts are needed to close the remaining gaps in our understanding of species. Here, we summarize the lessons learned from species-specific studies, carried out by our group over the last several decades, of near-shore microalgal blooms. Data acquired from research and monitoring programs greatly enhanced our knowledge of species composition, the conditions that trigger bloom events and those that determine both their recurrence and their intensity. Our own efforts consisted of: i) descriptions of new species; ii) first-time detections in the investigated areas; iii) blooms of rare species; iv) the identification of introduced species; and v) insights into species dispersal mechanisms. Most importantly, our studies opened up novel areas of research, focusing on previously unrecognized life-cycle pathways and the reversibility of the sexual stage in dinoflagellates. Thus, new paradigms of bloom dynamics are conceivable, e.g., the formation and maintenance of small-scale coastal blooms despite physical constrains. Accordingly, interpretations of bloom dynamics, persistence, and recurrence require a renewed examination of the biological behaviors of organisms and their environmental interactions, based on detailed taxonomy and appropriately scaled studies of growth rates, life cycles, and adaptive strategies, in an approach that distinguishes between broad concepts and species-specific characteristics

Anderson, Donald M. ... et. al.-- Global Ecology and Oceanography of Harmful Algal Blooms (GEOHAB) Synthesis Open Science Meeting, 24-26 April 2013, Paris, France.-- 2 pages, Many harmful algal bloom (HAB) species produce dormant cysts or resting spores during their life histories. Some also produce temporary or “pellicle” cysts that are less resistant, but which still provide a refuge during difficult conditions. Hereafter, for convenience, these will all be included under the umbrella term “resting stage.” The resulting alternation between a dormant, resting stage and a vegetative existence in the plankton is critically important in many aspects of bloom dynamics. Resting stage germination provides the inoculum for blooms, and the transformation back to the resting state can remove substantial numbers of vegetative cells from the population and act as a major factor in bloom decline, while also providing the inoculum for future blooms. [...]

1th Med-GIG WG CW Phytoplankton Meeting 3rd I.C. Phase, 3-4 March 2014, Barcelona