Description: © The Author(s), 2017. This is the author's version of the work. It is posted here under a nonexclusive, irrevocable, paid-up, worldwide license granted to WHOI. It is made available for personal use, not for redistribution. The definitive version was published in Harmful Algae 63 (2017): 32-44, doi:10.1016/j.hal.2017.01.008.

Description: Photosynthetic species of the dinoflagellate genus Cochlodinium such as C. polykrikoides, one of the most harmful bloom-forming dinoflagellates, have been extensively investigated. Little is known about the heterotrophic forms of Cochlodinium, such as its type species, Cochlodinium strangulatum. This is an uncommon, large (~200 μm long), solitary, and phagotrophic species, with numerous refractile bodies, a central nucleus enclosed in a distinct perinuclear capsule, and a cell surface with fine longitudinal striae and a circular apical groove. The morphology of C. polykrikoides and allied species is different from the generic type. It is a bloom-forming species with single, two or four-celled chains, small cell size (25–40 μm long) with elongated chloroplasts arranged longitudinally and in parallel, anterior nucleus, eye-spot in the anterior dorsal side, and a cell surface smooth with U-shaped apical groove. Phylogenetic analysis based on LSU rDNA sequences revealed that C. strangulatum and C. polykrikoides/C. fulvescens formed two distally related, independent lineages. Based on morphological and phylogenetic analyses, the diagnosis of Cochlodinium is emended and C. miniatum is proposed as synonym of C. strangulatum. The new genus Margalefidinium gen. nov., and new combinations for C. catenatum, C. citron, C. flavum, C. fulvescens and C. polykrikoides are proposed.

Description: F.G. was supported by the Brazilian Conselho Nacional de Desenvolvimento Científico e Tecnológico [grant number BJT 370646/2013–14]. Support for M.L.R. and D.M.A. was provided through the Woods Hole Center for Oceans and Human Health, National Science Foundation [grant number OCE–1314642] and National Institute of Environmental Health Sciences [grant number 1–P01–ES021923–01].

Description: On May 8 and 9, 1989, a consultation of experts was convened at the Woods Hole Oceanographic Institution to discuss the possible link between natural biotoxins and recent mass mortalities of humpback whales and bottlenose dolphins along the eastern coast of the United States. The focus was on the possible role of dinoflagellate toxins in these events. The objectives of the meeting were to review and assess the existing evidence and to recommend research priorities and needs.

Description: Funding was provided by NOAA, National Marine Fisheries Service, Woods Hole Oceanographic Institution Coastal Research Center through a grant from the Andrew W. Mellon Foundation and the Woods Hole Oceanographic Institution Sea Grant Program under Grant NA86-D-SW90 (Project R/B - 92 and M/O-2).

Description: Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part I: Oceanographic Research Papers 58 (2011): 1130-1146, doi:10.1016/j.dsr.2011.08.009.

Description: Observations and numerical modeling indicate that a mesoscale anti-cyclonic eddy formed south of Cape Ann at the northern entrance of Massachusetts Bay (MB) during May 2005, when large river discharges in the western Gulf of Maine and two strong Nor’easters passing through the regions led to an unprecedented toxic Alexandrium fundyense bloom (red tide). Both model results and field measurements suggest that the western Maine coastal current separated from Cape Ann around May 7-8, and the eddy formed on around May 10. The eddy was trapped at the formation location for about a week before detaching from the coastline and moving slowly southward on May 17. Both model results and theoretical analysis suggest that the separation of the coastal current from the coast and subsequent eddy formation were initiated at the subsurface by an adverse pressure gradient between Cape Ann and MB due to the higher sea level set up by onshore Ekman transport and higher density in downstream MB. After the formation, the eddy was maintained by the input of vorticity transported by the coastal current from the north, and local vorticity generation around the cape by the horizontal gradients of wind-driven currents, bottom stress, and water density induced by the Merrimack River plume. Observations and model results indicate that the anti-cyclonic eddy significantly changed the pathway of nutrient and biota transport into the coastal areas and enhanced phytoplankton including Alexandrium abundances around the perimeter of the eddy and in the western coast of MB.

Description: MJ was partially supported by the MWRA for this work. Support for DMA and many of the cruise observations was provided by the GOMTOX project through NOAA Grant NA06NOS4780245. Additional cruise support came from NSF grant OCE-0430724, DMS-0417769 and NIEHS grant 1P50-ES01274201 (Woods Hole Center for Oceans and Human Health) and through NOAA ECOHAB Grant NA09NOS4780193.

Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Anderson, D. M., Fensin, E., Gobler, C. J., Hoeglund, A. E., Hubbard, K. A., Kulis, D. M., Landsberg, J. H., Lefebvre, K. A., Provoost, P., Richlen, M. L., Smith, J. L., Solow, A. R., & Trainer, V. L. Marine harmful algal blooms (HABs) in the united states: history, current status and future trends. Harmful Algae, 102, (2021): 101975, https://doi.org/10.1016/j.hal.2021.101975.

Description: Harmful algal blooms (HABs) are diverse phenomena involving multiple. species and classes of algae that occupy a broad range of habitats from lakes to oceans and produce a multiplicity of toxins or bioactive compounds that impact many different resources. Here, a review of the status of this complex array of marine HAB problems in the U.S. is presented, providing historical information and trends as well as future perspectives. The study relies on thirty years (1990–2019) of data in HAEDAT - the IOC-ICES-PICES Harmful Algal Event database, but also includes many other reports. At a qualitative level, the U.S. national HAB problem is far more extensive than was the case decades ago, with more toxic species and toxins to monitor, as well as a larger range of impacted resources and areas affected. Quantitatively, no significant trend is seen for paralytic shellfish toxin (PST) events over the study interval, though there is clear evidence of the expansion of the problem into new regions and the emergence of a species that produces PSTs in Florida – Pyrodinium bahamense. Amnesic shellfish toxin (AST) events have significantly increased in the U.S., with an overall pattern of frequent outbreaks on the West Coast, emerging, recurring outbreaks on the East Coast, and sporadic incidents in the Gulf of Mexico. Despite the long historical record of neurotoxic shellfish toxin (NST) events, no significant trend is observed over the past 30 years. The recent emergence of diarrhetic shellfish toxins (DSTs) in the U.S. began along the Gulf Coast in 2008 and expanded to the West and East Coasts, though no significant trend through time is seen since then. Ciguatoxin (CTX) events caused by Gambierdiscus dinoflagellates have long impacted tropical and subtropical locations in the U.S., but due to a lack of monitoring programs as well as under-reporting of illnesses, data on these events are not available for time series analysis. Geographic expansion of Gambierdiscus into temperate and non-endemic areas (e.g., northern Gulf of Mexico) is apparent, and fostered by ocean warming. HAB-related marine wildlife morbidity and mortality events appear to be increasing, with statistically significant increasing trends observed in marine mammal poisonings caused by ASTs along the coast of California and NSTs in Florida. Since their first occurrence in 1985 in New York, brown tides resulting from high-density blooms of Aureococcus have spread south to Delaware, Maryland, and Virginia, while those caused by Aureoumbra have spread from the Gulf Coast to the east coast of Florida. Blooms of Margalefidinium polykrikoides occurred in four locations in the U.S. from 1921–2001 but have appeared in more than 15  U.S. estuaries since then, with ocean warming implicated as a causative factor. Numerous blooms of toxic cyanobacteria have been documented in all 50  U.S. states and the transport of cyanotoxins from freshwater systems into marine coastal waters is a recently identified and potentially significant threat to public and ecosystem health. Taken together, there is a significant increasing trend in all HAB events in HAEDAT over the 30-year study interval. Part of this observed HAB expansion simply reflects a better realization of the true or historic scale of the problem, long obscured by inadequate monitoring. Other contributing factors include the dispersion of species to new areas, the discovery of new HAB poisoning syndromes or impacts, and the stimulatory effects of human activities like nutrient pollution, aquaculture expansion, and ocean warming, among others. One result of this multifaceted expansion is that many regions of the U.S. now face a daunting diversity of species and toxins, representing a significant and growing challenge to resource managers and public health officials in terms of toxins, regions, and time intervals to monitor, and necessitating new approaches to monitoring and management. Mobilization of funding and resources for research, monitoring and management of HABs requires accurate information on the scale and nature of the national problem. HAEDAT and other databases can be of great value in this regard but efforts are needed to expand and sustain the collection of data regionally and nationally.

Description: Support for DMA, MLR, and DMK was provided through the Woods Hole Center for Oceans and Human Health (National Science Foundation grant OCE-1840381 and National Institutes of Health grants NIEHS‐1P01-ES028938–01) and the U.S. National Office for Harmful Algal Blooms with funding from NOAA's National Centers for Coastal Ocean Science (NCCOS) through the Cooperative Institute for the North Atlantic Region (CINAR) (NA14OAR4320158, NA19OAR4320074). Funding for KAL and DMA was provided by the National Oceanic and Atmospheric Administration National Centers for Coastal Ocean Science Competitive Research Program under award NA20NOS4780195 to the Woods Hole Oceanographic Institution and NOAA's Northwest Fisheries Science Center. We also acknowledge support for A.H. from the National Oceanic and Atmospheric Administration [NOAA] Office of Ocean and Coastal Resource Management Award NA19NOS4780183, C.J.G from NOAA-MERHAB (NA19NOS4780186) and (NA16NOS4780189) for VLT Support was also received for JLS, CJG, and VLT from NOAA-NCCOS-ECOHAB under awards NA17NOS4780184 and NA19NOS4780182. This is ECOHAB publication number ECO972.

Description: Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Desalination 293 (2012): 1-6, doi:10.1016/j.desal.2012.02.014.

Description: Over the last several decades, countries throughout the world have experienced an escalating and worrisome trend in the incidence of harmful algal blooms (HABs). A concern is that highly potent algal toxins might be retained in the treated water, posing a threat to human health. Seawater contaminated with saxitoxins, domoic acid, okadaic acid, and brevetoxins was desalinated using small (〈100 mL capacity) reverse osmosis and distillation equipment. Analyses of desalinated water samples indicated efficient removal of the four toxins to greater than 99%, except brevetoxins for which some carryover was observed during distillation. Hypochlorite concentrations of 4 ppm or higher were sufficient to react with all of the saxitoxins, domoic acid and okadaic acid in the samples that contained initial toxin concentrations up to 1,250 ng.mL-1 . Brevetoxins appeared to be unaffected in experiments in which the toxins were exposed to up to 30 ppm hypochlorite in seawater at 35 °C for 60 min. These results and their implications in terms of desalination plant design and operation are discussed.

Description: This work was also supported in part by the Woods Hole Center for Oceans and Human Health (NSF Grants OCE-0430724 and OCE-0911031; NIEHS Grant P50ES012742-01) and Effects of Inhaled Florida Red Tide Brevetoxins (NIH Grant P01 ES010594-09).

Description: Author Posting. © The Author(s), 2013. This is the author's version of the work. It is posted here by permission of Elsevier for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part II: Topical Studies in Oceanography 103 (2014): 6-26, doi:10.1016/j.dsr2.2013.10.002.

Description: Here we document Alexandrium fundyense cyst abundance and distribution patterns over nine years (1997 and 2004-2011) in the coastal waters of the Gulf of Maine (GOM) and identify linkages between those patterns and several metrics of the severity or magnitude of blooms occurring before and after each autumn cyst survey. We also explore the relative utility of two measures of cyst abundance and demonstrate that GOM cyst counts can be normalized to sediment volume, revealing meaningful patterns equivalent to those determined with dry weight normalization.Cyst concentrations were highly variable spatially. Two distinct 1 seedbeds (defined here as accumulation zones with 〉 300 cysts cm-3) are evident, one in the Bay of Fundy (BOF) and one in mid-coast Maine. Overall, seedbed locations remained relatively constant through time, but their area varied 3-4 fold, and total cyst abundance more than 10 fold among years. A major expansion of the mid-coast Maine seedbed occurred in 2009 following an unusually intense A. fundyense bloom with visible red-water conditions, but that feature disappeared by late 2010. The regional system thus has only two seedbeds with the bathymetry, sediment characteristics, currents, biology, and environmental conditions necessary to persist for decades or longer. Strong positive correlations were confirmed between the abundance of cysts in both the 0-1 and the 0-3 cm layers of sediments in autumn and geographic measures of the extent of the bloom that occurred the next year (i.e., cysts → blooms), such as the length of coastline closed due to shellfish toxicity or the southernmost latitude of shellfish closures. In general, these metrics of bloom geographic extent did not correlate with the number of cysts in sediments following the blooms (blooms → cysts). There are, however, significant positive correlations between 0-3 cm cyst abundances and metrics of the preceding bloom that are indicative of bloom intensity or vegetative cell abundance (e.g., cumulative shellfish toxicity, duration of detectable toxicity in shellfish, and bloom termination date). These data suggest that it may be possible to use cyst abundance to empirically forecast the geographic extent of the forthcoming bloom and, conversely, to use other metrics from bloom and toxicity events to forecast the size of the subsequent cyst population as the inoculum for the next year’s bloom. This is an important step towards understanding the excystment/encystment cycle in A. fundyense bloom dynamics while also augmenting our predictive capability for this HAB-forming species in the GOM.

Description: Research support provided by the ECOHAB Grant program through NOAA Grants NA06NOS4780245 and NA09NOS4780193, and through the Woods Hole Center for Oceans and Human Health, National 1 Science Foundation (NSF) Grants OCE-0430724, OCE-0911031, and OCE-1314642; and National Institute of Environmental Health Sciences (NIEHS) Grants 1-P50-ES012742-01 and 1-P01-ES021923-01, and funding through the states of ME, NH, and MA. We are also grateful for event response funding provided for many of the cruises. Funding for J.L. Martin was provided by Fisheries and Oceans Canada.

Description: Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Annual Reviews for personal use, not for redistribution. The definitive version was published in Annual Review of Marine Science 4 (2012): 143-176, doi:10.1146/annurev-marine-120308-081121.

Description: The public health, tourism, fisheries and ecosystem impacts from harmful algal blooms (HABs) have all increased over the last few decades. This has led to heightened scientific and regulatory attention, and the development of many new technologies and approaches for research and management. This in turn, is leading to significant paradigm shifts with regard to, e.g., our interpretation of the phytoplankton species concept (strain variation), the dogma of their apparent cosmopolitanism, the role of bacteria and zooplankton grazing in HABs, and our approaches to investigating the ecological and genetic basis for the production of toxins and allelochemicals. Increasingly, eutrophication and climate change are viewed and managed as multifactorial environmental stressors that will further challenge managers of coastal resources and those responsible for protecting human health. Here we review HAB science with an eye towards new concepts and approaches, emphasizing, where possible, the unexpected yet promising new directions that research has taken in this diverse field.

Description: Support to DMA was provided by the National Institute of Environmental Health Sciences (1-P50-ES012742) and the National Science Foundation through the Woods Hole Center for Oceans and Human Health (OCE-0430724), and by NOAA Grants NA09NOS4260212 and NA09OAR4320129.

Description: Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Elsevier for personal use, not for redistribution. The definitive version was published in Ocean & Coastal Management 52 (2009): 342-347, doi:10.1016/j.ocecoaman.2009.04.006.

Description: Virtually every coastal country in the world is affected by harmful algal blooms (HABs, commonly called “red tides”). These phenomena are caused by blooms of microscopic algae. Some of these algae are toxic, and can lead to illness and death in humans, fish, seabirds, marine mammals, and other oceanic life, typically as a result of the transfer of toxins through the food web. Sometimes the direct release of toxic compounds can be lethal to marine animals. Non-toxic HABs cause damage to ecosystems, fisheries resources, and recreational facilities, often due to the sheer biomass of the accumulated algae. The term “HAB” also applies to non-toxic blooms of macroalgae (seaweeds), which can cause major ecological impacts such as the displacement of indigenous species, habitat alteration and oxygen depletion in bottom waters. Globally, the nature of the HAB problem has changed considerably over the last several decades. The number of toxic blooms, the resulting economic losses, the types of resources affected, and the number of toxins and toxic species have all increased dramatically. Some of this expansion has been attributed to storms, currents and other natural phenomena, but human activities are also frequently implicated. Humans have contributed by transporting toxic species in ballast water, and by adding massive and increasing quantities of industrial, agricultural and sewage effluents to coastal waters. In many urbanized coastal regions, these inputs have altered the size and composition of the nutrient pool which has, in turn, created a more favorable nutrient environment for certain HAB species. The steady expansion in the use of fertilizers for agricultural production represents a large and worrisome source of nutrients in coastal waters that promote some HABs. The diversity in HAB species and their impacts presents a significant challenge to those responsible for the management of coastal resources. Furthermore, HABs are complex oceanographic phenomena that require multidisciplinary study ranging from molecular and cell biology to large-scale field surveys, numerical modelling, and remote sensing from space. Our understanding of these phenomena is increasing dramatically, and with this understanding come technologies and management tools that can reduce HAB incidence and impact. Here I summarize the global HAB problem, its trends and causes, and new technologies and approaches to monitoring, control and management, highlighting molecular probes for cell detection, rapid and sensitive toxin assays, remote sensing detection and tracking of blooms, bloom control and mitigation strategies, and the use of large-scale physical/biological models to analyze past blooms and forecast future ones.

Description: : NOAA Cooperative Agreement NA17RJ1223; NIEHS Grant 1 P50 ES012742 and NSF Grant OCE-0430724 through the Woods Hole Center for Oceans and Human Health; NSF Grant OCE-0402707 and NOAA Grant NA05NOS4191149 through the NOAA/UNH Cooperative Institute for Coastal and Estuarine Environmental Technology.