Toxic and Noxious Algal Blooms of Southern California, and Their Ecosystem Impacts

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Toxic and Noxious Algal Blooms of Southern
California, and Their Ecosystem Impacts
David A. Caron Marine Environmental
Biology Department of Biological
Sciences University of Southern California
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A growing problem worldwide?
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Our Local HAB issues (from bad-to-worst)
Fairly innocous red tides Lingulodinium
polyedrum Prorocentrum spp. ( several other
dinoflagellates) Noxious foams Phaeocystis
globosa Toxic truly species Dinophysis spp.
(DSP) Alexandrium spp. (PSP) Pseudo-nitzschia
spp. (ASP) And some new players on the
scene Cochlodinium catenatum (fish
kills) Raphidophytes (Chattonella, Heterosigma)
(fish kills)
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Massive red tide off CA caused by the
dinoflagellate Noctiluca (colorfulbut fairly
innocuous)
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Lingulodinium polyedrum
A red tide without toxic consequences so
far. (potential producer of yessotoxin)
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June 2005
Yessotoxin
-attacks the cardiac muscle in mice lipophilic,
sulphated compound (YTX) a brevetoxin-type
polyether
Lingulodinium polyedrum (Gonyaulax
polyhedra) Also Protoceratium reticulatum
Recent demonstration of the production of
yessotoxin in central CA. No knowledge in our
area.
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Photo from Van Edmond
Phaeocystis spp.
Near Santa Barbara
Noxious species disruption of normal food web
structure and function. Dimethyl sulfide
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Prorocentrum micans King Harbor, Redondo Beach
(May 2006)
(unknown if a toxin was produced during this
bloom)
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Okadaic Acid (Diarrhetic Shellfish Poisoning) (
derivatives, dinophysistoxins ) Lipophilic
compounds, causing diarrhea, nausea, vomiting,
moderate to severe abdominal pain and cramps, and
chills. No known fatalities, but Strong
tumor promoter. Protein phosphatase-1 (PP1)
inhibitor, an enzyme that plays a key role in
dephosphorylation in numerous biological
processes including cell cycle regulation.
Dinophysis spp. but alsoProrocentrum spp.
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Known toxins in SCB
Saxitoxins
Domoic Acid
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10 year frequency of HAB events along U.S.
coastal waters. from The Harmful Algae webpage
(http//www.whoi.edu/redtide/index.html)
Saxitoxin
Domoic acid
Sparse measurements (CA Department of Health
Services)
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Alexandrium spp. Cochlodinium (Gymnodinium)
catenatum Pyrodinium bahamense var. compressa
Saxitoxin (Paralytic Shellfish Poisoning) And few
dozen similar compounds, varying in toxicity. A
selective sodium channel blocker, it blocks
passage of nerve impulses.
Present in SCB, but little knowledge of
occurrence
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10 year frequency of HAB events along U.S.
coastal waters. from The Harmful Algae webpage
(http//www.whoi.edu/redtide/index.html)
Saxitoxin
Domoic acid
Sparse measurements (CA Department of Health
Services)
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From Santa Cruz Sentinel (2006)
150 years of the Sentinel Thousands of birds
floundering in streets EDITOR'S NOTE The
Sentinel is celebrating its 150th year in 2006 by
reaching into our archives to republish some of
the noteworthy stories out of the past. The
following story was printed in the Santa Cruz
Sentinel on Aug. 18, 1961. By Wally Trabing A
massive flight of sooty shearwaters, fresh from a
feast of anchovies, collided with shore side
structures from Pleasure Point to Rio del Mar
during the night. Residents, especially in the
Pleasure Point and Capitola area were awakened
about 3 a.m. today by the rain of birds, slamming
against their homes. Dead, and stunned, seabirds
littered the streets and roads in the foggy,
early dawn. Startled by the invasion, residents
rushed out on their lawns with flashlights, then
rushed back inside, as the birds flew toward
their light. Television aerial supports were
severed, and one power line was shorted out about
4 a.m. on Merrill avenue when the birds hitting
the lines slapped them together
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Domoic Acid Amnesic Shellfish Poisoning (ASP) gt
1500 mammal strandings in 2003
Symptoms in humans Nausea, vomiting, abdominal
cramps, headache, dizziness, confusion,
disorientation, short term memory loss motor
weakness, seizures, cardiac arrhythmia, coma,
rarely death.
Around here, marine mammals and seabirds take the
worst of it.
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Pseudo-nitzschia
Domoic Acid Amnesic Shellfish Poisoning gt 1500
mammal strandings in 2003
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DA constitutes a significant risk for humans in
other regions as ASP (Amnesic Shellfish
Poisoning)...
but may be primarily an issue for marine
animals in the SCB, via links in food-webs.
Planktivorous fish (e.g. anchovy, sardines)
Pacific sand crab
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Trophic Connections
Planktivorous fish
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12.7
6.22
5.64
6.61
1.95
0.001
0.002
3.33
0.09
0.008
0.16
0.001
0.036
May 2003
A local problem or a case of transport into our
waters?
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Minor Bloom in 2004
Pseudo-nitzschia abundance and domoic acid
concentrations at a single station during 2004

Transport to deep coastal seafloor
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2006 Bloom Dynamics
nanograms particulate DA per mL Seawater
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(No Transcript)
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Domoic acid concentrations in plankton, samples
taken from marine mammals and planktivorous fish
during 2006.
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Results of 2006
DA concentrations are shown in nanograms per mL
or nanograms per mg weight sample from animals
suspected of DA poisoning
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Why toxin production?

• Allelopathy (kill your competitors!)
• -major nutrient acquisition
• (P, Si)
• Grazer Deterence (tasting bad is good)
• Metals (too many, or not enough)
• (Fe, Cu)

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Next steps
Demonstrating presence/absence of HAB species and
toxins new toxin analyses coming on
line. molecular identification of HAB
species. Characterizing spatial and temporal
distributions continue cruisers on an ad-hoc
basis buoys and gliders (MERHAB) nutrient
inventory
A collaborative/multidisciplinary approach is
fundamental. Causes are complex there is no
silver bullet. Ultimate goal Developing
predictive understanding
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Thank you!