Dietary exposure to harmful algal bloom (HAB) toxins in the endangered manatee (Trichechus manatus latirostris) and green sea turtle (Chelonia mydas) in Florida, USA

Evidence of sewage-driven eutrophication and harmful algal blooms in Florida's Indian River Lagoon

“…Ongoing research suggests that Gracilaria tikvahiae McLachlan, an abundant member of the drift algal community that is widely available as food to manatees, is producing N-containing cyanogenic glycosides (Peter Moeller et al, unpublished data) that are known to cause severe health problems, and even death, in humans (Seigler, 1991;Halstead and Haddock, 1992;Noguchi et al, 1994). In addition to the potential lethal effects of these macroalgal toxins, other more common HAB toxins, including brevetoxin, saxitoxin, and okadaic acid, are known to have sublethal effects on federally endangered manatees and green sea turtles in Florida (Capper et al, 2013). Because the eutrophication problem in the IRL appears to be driven largely by N from wastewater, there is a critical and urgent need for improved sewage collection and treatment -specifically involving Advanced Wastewater Treatment (AWT) and nutrient removal.…”

Differential inimical effects of Alexandrium spp. and Karenia spp. on cleavage, hatching, and two larval stages of Japanese pearl oyster Pinctada fucata martensii

“…In aquatic environments, high biomass blooms have caused mass mortalities of a variety of aquatic organisms through predation, starvation, shading or anoxic conditions (Gainey and Shumway, 1991;Shumway, 1990;Rensel, 1993;Smayda, 1997;Landsberg, 2002). On the other hand, diverse groups of HAB species induce acute, chronic, and sublethal effects in aquatic organisms, including reptiles, mammals and seabirds, as a result of the production of biotoxins and/or other bioactive compounds with poorly understood allelopathic activities, many of which are yet to be characterized or even discovered (Shumway, 1990(Shumway, , 1995Scholin et al, 2000;Shumway et al, 2003;Flewelling et al, 2005;Grané li et al, 2008;Lefebvre et al, 2010;Capper et al, 2013).…”

Large-Scale Sea Turtle Mortality Events in El Salvador Attributed to Paralytic Shellfish Toxin-Producing Algae Blooms

“…This evidence includes postmortem findings consistent with acute toxicosis, detection of relatively high concentrations of PST in gastrointestinal contents and tissues, observation of PST-producing dinoflagellates within gastrointestinal contents, and remote-sensing data suggestive of dinoflagellate blooms concurrent with sea turtle mortality. In Chelonia mydas, higher concentrations of STX has been found in the gastro-intestinal tract contents rather than tissues (Capper et al, 2013). Toxicity thresholds have not been defined for PST in chelonians or other reptiles.…”