Physical, Chemical, and Genetic Differences Associated
with Harmful Marine Phytoplankton: Heterosigma
and Domoic Acid Producers
Banse, K.; Cattolico, R.A.; and Taub, F.B.
National Marine Fisheries Service, Northwest Region, 7600
Sand Point Way, NE, BIN C15700, Bldg. 1, Seattle, WA 98115.
PHONE: (206) 526-6117
of this project were: to define the nutrient and physical
conditions that cause Heterosigma to be toxic
to certain fish; develop a chemi-luminescent probe for
the rapid identification; and, survey the regional and
seasonal distribution of Pseudonitzschia, a planktonic
diatom that produces domoic acid. Researchers found
that decreased surface salinity causes Heterosigma
to become toxic, or the mode of toxicity, were not evident.
Development of a fluorescent detection method for Heterosigma
was initiated. A methodology was developed to induce
toxicity for Heterosigma. Water samples were collected
and examined for the presence of Pseudonitzschia and
other harmful species. Lists of all phytoplankton species
found were enumerated in an attempt to understand more
about their spatial and temporal distribution and abundance
in western Washington marine waters. Thirteen cultures
of Pseudonitzschia were isolated from samples
taken during the project.