WWW.WAS.ORG • WORLD AQUACULTURE • MARCH 2018 61 limited by gas diffusion. Increased temperature is expected in many regions, resulting in invasion of more tropical species poleward and increasing the length of the summer growing season. Many of the most common blooms occur during late summer, when water is calm, stagnant, and nutrient-rich. As areas become warmer, it is likely that freshwaters will evaporate more quickly, resulting in higher mineral content of these waters so equivalent salinity will increase. This will mean that formerly marine species will have suitable environment to occur closer to freshwater sources, and species adapted to higher salinity will encroach on freshwaters. Also, the abundance of benthic taxa will increase in areas where water column depth decreases, which is expected from higher water use and evaporation rates, and lower precipitation rates. Lastly, lowered water levels and more erratic weather patterns will increase introduction of new species to aquaculture systems under our current climatological conditions. Implications The importance of these bioactive metabolites can be direct, by death of reared organisms or by decreasing feed conversion efficiency, thereby costing more money to produce a marketable product. To date, there is no published information on how many of the co-occurring toxins impact fish at chronic low-level dosages. Evidence from multi-pesticide and mutagenic compound combinations suggests that an impact on growth and reproduction is likely. The regulation of harmful algal blooms is likely to fall on aquaculture researchers and producers rather than direct assistance from federal monitoring agencies. In our view, this puts producers and distributors at risk for legal action for sale of toxic products. To safeguard aquaculture products, it is more important than ever to be diligent in monitoring water quality — including algal community composition — in ponds. Notes Paul V. Zimba and I-Shuo Huang, Center for Coastal Studies, Texas A&M University Corpus Christi, 6300 Ocean Dr., Corpus Christi, TX USA 78412 References Bates, S.S., C.J. Bird, A.S.W. de Freitas, R. Foxall, M. Gilgan, L.A. Hanic, G.R. Johnson, A.W. McCulloch, P. Odense, R. Pocklington, M.A. Quilliam, P.G. Sim, J.C. Smith, D.V. Subba-Rao, E.C-D. Todd, J.A. Walter and J.L.C. Wright.1989. Pennate diatom Nitzschia pungens as the primary source of domoic acid, a toxin in shellfish from eastern Prince Edward Island, Canada. Canadian Journal of Fisheries and Aquatic Sciences 46:1203-1215. Bertin, M.J., P.V. Zimba, K.R. Beauchesne, K.M. Huncik and P.D.R. Moeller. 2012. Identification of toxic fatty acid amides isolated from the harmful alga Prymnesium parvum Carter. Harmful Algae 20:111-116. Deeds, J.R., D.E. Terlizzi, J.E. Adolf, D.K. Stoecker and A.E. Place. 2002. Toxic activity from cultures of Karlodinium micrum (=Gyrodinium galatheanum) (Dinophyceae)—a dinoflagellate associated with fish mortalities in an estuarine aquaculture facility. Harmful Algae 1:169-189. Haque, S.M. and Y. Onoue. 2002. Variation in toxin composition of two harmful raphidophytes, Chantonella antiqua and Chatonella marina, at different salinities. Environmental Toxicology 17:113-118. Richardson, L.L., R. Sekar, J.L. Meyers, M. Gantar, J.D. Voss, L. Kaczmarsky, E.R. Remily, G.L. Boyer and P.V. Zimba. 2007. The presence of the cyanobacterial toxin microcystin in black band disease of corals. Federation of European Microbiological Sciences Microbiological Letters 272:182-187. Zimba, P.V., L. Khoo, P.S. Gaunt, S. Brittain and W.W. Carmichael. 2001. Confirmation of catfish, Ictalurus puntatus (Rafinesque), mortality from Microcystis toxins. Journal of Fish Diseases 24:41-47. Zimba, P.V., M. Rowan and R.E. Triemer. 2004. Identification of euglenoid algae that produce ichthyotoxin(s). Journal of Fish Diseases 65:35-38. Zimba, P.V., I.-S. Huang, D. Gutierrez, W.S. Shin, M. Bennett and R. Triemer. 2017. Euglenophycin is produced in at least six species of euglenoid algae and six of seven strains of Euglena sanguinea. Harmful Algae 63:79-84.
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