[MARMAM] Harmful algal toxins in marine mammals

Spencer Fire Spencer.Fire at noaa.gov
Mon Jan 3 07:50:11 PST 2011

Dear colleagues,

I am pleased to announce the following new articles regarding exposure of
marine mammals in US coastal waters to harmful algal blooms.  For further
details please feel free to contact me (spencer.fire at noaa.gov). 


Fire, Spencer E., Zhihong Wang, Meridith Byrd, Heidi R. Whitehead, Jeff
Paternoster, Steve L. Morton, Co-occurrence of multiple classes of harmful
algal toxins in bottlenose dolphins (Tursiops truncatus) stranding during an
unusual mortality event in Texas; USA. Harmful Algae,
DOI:10.1016/j.hal.2010.12.001. http://dx.doi.org/10.1016/j.hal.2010.12.001


During February-April 2008, an unusual mortality event occurred in Texas
coastal waters that resulted in over 100 bottlenose dolphin (Tursiops
truncatus) deaths.  This mortality event overlapped spatially and temporally
with a harmful algal bloom (HAB) composed of the toxin-producing genera
Dinophysis spp. and Prorocentrum spp., and was associated with shellfish bed
closures due to HAB toxins.  A bloom of the toxin-producing diatom
Pseudo-nitzschia pungens was also detected in Texas coastal waters in early
April, towards the end of the dolphin mortality event.  Analysis of dolphin
gastrointestinal contents collected during this event demonstrated the
presence of the HAB toxins domoic acid and okadaic acid in association with
these blooms, as well as evidence of brevetoxin exposure in the absence of
an associated K. brevis bloom.  Historical dolphin stranding data for Texas
waters indicate seasonal stranding peaks similar to the present study,
indicating a need for investigating potential HAB involvement in mass
strandings in previous years and in future events.  This study marks the
first reported occurrence of okadaic acid in marine mammals, and documents a
unique co-occurrence of multiple HAB toxins associated with an unusual
mortality event.  Texas waters harbor a high diversity of HAB events
relative to other coastal regions, and this study highlights the importance
of efforts to understand the impacts of such HAB events on the health of
Texas marine wildlife.


Fire, Spencer E., Zhihong Wang, Michelle Berman, Gregg W. Langlois, Steve L.
Morton, Emily Sekula-Wood, Claudia R. Benitez-Nelson (2010). Trophic
transfer of the harmful algal toxin domoic acid as a cause of death in a
minke whale (Balaenoptera acutorostrata) stranding in southern California.
Aquatic Mammals 36: 342-350. DOI: 10.1578/am.36.4.2010.342


Unusually high concentrations of the neurotoxin domoic acid (DA) were
detected in a minke whale (Balaenoptera acutorostrata) carcass recovered
during a severe harmful algal bloom (HAB), which occurred in southern
California in April 2007. Cell fragments of the toxigenic diatom
Pseudo-nitzschia australis were observed in whale gastric fluid and feces,
corresponding to a dominance of Pseudo-nitzschia spp. in the phytoplankton
community at the time of stranding. A high abundance of otoliths from a
prominent DA vector, the northern anchovy (Engraulis mordax), were recovered
in whale stomach contents, indicating trophic transfer of DA via the food
web. Whale feces contained 258 μg DA per gram sample, exceeding DA
concentrations reported for any marine mammal. DA intoxication was
identified as the cause of mortality of this animal, expanding on the
limited understanding of the impacts of DA-producing HABs on large whales.


Happy new year,


Spencer Fire


NOAA Marine Biotoxins Program <http://www.chbr.noaa.gov/habar/eroart.aspx> 
219 Fort Johnson Road
Charleston, SC 29412

spencer.fire at noaa.gov



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.uvic.ca/pipermail/marmam/attachments/20110103/51482e16/attachment.html>

More information about the MARMAM mailing list