Publication Details
Saxitoxin exposure in an endangered fish: association of a shortnose sturgeon mortality event with a harmful algal bloom
Author(s): Fire, S.E.; J. Pruden; D. Couture; Z. Wang; M-Y. D. Bottein; B.L. Haynes; T. Knott; D. Bouchard; A. Lichtenwalner; G. Wippelhauser
NCCOS Center: CCEHBR (http://chbr.noaa.gov)
Publication Type: Journal Article
Journal Title: Marine Ecology Progress Series
Date of Publication: 2012
Reference Information: 460
145-153
Keywords: Saxitoxin; sturgeon; harmful algal bloom; paralytic shellfish toxin; HAB; Acipenser brevirostrum; Maine
Abstract: Saxitoxin (STX)-producing blooms of the toxic dinoflagellate genus Alexandrium
have been responsible for devastating ecosystem-wide impacts in coastal waters of the northeastern
USA. In the summer of 2009, a severe Alexandrium bloom in New England coastal waters cooccurred
with a shortnose sturgeon Acipenser brevirostrum mortality event in Sagadahoc Bay,
Maine, USA. Thirteen individuals of this endangered fish species were found dead on 10 July
2009, and this die-off was associated with extremely high Alexandrium cell densities, recordbreaking
toxin burdens (>80 000 ng g-1) in shellfish, and closures of shellfish beds affecting nearly
the entire Maine coastline. STX-like activity was detected in sturgeon (n = 3) stomach contents
and liver and gill tissues via neuroblastoma assay and receptor-binding assay at con centrations
ranging between 37 and 2300 ng STX-eq. g-1 (STX equivalents per gram sample). Stomach
content analyses of the 3 necropsied sturgeon carcasses showed a large number of amethyst gem
clams Gemma gemma. Liquid chromatography-mass spectrometry confirmed the presence of
STX and related congeners in sturgeon stomach contents, at concentrations between 311 and
743 ng g-1. The present study marks the first reported detection of STXs in shortnose sturgeon,
and provides evidence of trophic transfer of Alexandrium toxins as a potential cause of mortality
in this event, as well as a threat to the health of this endangered population of fish.
Availability: MEPS