Biogeography of toxic dinoflagellates in the genusAlexandrium from the northeastern United States and Canada

Interannual variability of Alexandrium fundyense abundance and shellfish toxicity in the Gulf of Maine

“…Both the onset and demise tend to occur later in the eastern Gulf of Maine, with the principal period of toxicity being June through August (Bean et al, submitted). In 1993, 1994, and 1998 It is notable that the successive changes in A. fundyense abundance and shellfish toxicity in the western Gulf of Maine have in all cases the same sign. Goodman and Grunfeld (1961) described a simple test for independence between time series based on these so-called comovements.…”

Testing for resistance of pelagic marine copepods to a toxic dinoflagellate

“…Casco Bay experiences recurrent blooms of toxic A. fundyense, whereas Great Bay has never experienced an A. fundyense bloom (Cohn et al, 1988;Anderson et al, 1994). Copepods were collected with a 200 lm mesh net and transported to the laboratory within 24 h of collection.…”

“…To measure toxin content of A. fundyense, toxins were extracted from replicate aliquots according to Anderson et al (1994) and analyzed by HPLC using methods of Oshima et al (1989) in our laboratory (the source for the saxitoxin (STX) standards was NRC, Halifax, Canada). Of the suite of saxitoxins present in A. fundyense, we quantified the most potent -STX, neosaxitoxin (NEO) and gonyautoxins I-IV (GTX 1-4) (Schantz, 1986;Indrasena and Gill, 1999).…”

Bioactive compounds of marine dinoflagellate isolates from western Greenland and their phylogenetic association within the genus Alexandrium

“…Comparing of toxin cell quota, or molar amount of toxin per cell, has been previously invoked to define Alexandrium populations as high, medium or low toxicity (e.g., Cembella et al, 1987;Anderson et al, 1994), but such analyses are complicated by high intrapopulation variability, toxin content variation over the culture cycle, discrepancies in comparing cultured isolates with natural populations, and the application of alternative analytical methods to determine cell toxin composition (Cembella, 1998). The cell toxin content is a much more unstable phenotypic characteristic than is the toxin compositional profile.…”