California HAB Bulletin

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What is the CA HAB Bulletin?

The purpose of this experimental product is to give the public and resource managers a quick outlook of recent toxic (marine) algal blooms in coastal California from models and aggregate data sets. Monthly to bi-monthly reports will synthesize model output, near real-time observations, and public health alerts to provide a more complete picture of the regional variability in harmful algal blooms.

What information is included in the Bulletin?

To date, the CA HAB Bulletin is focused on HABs caused by the diatom Pseudo-nitzschia spp. and its neurotoxin, domoic acid (DA), the cause of Amnesic Shellfish Poisoning in humans. The bulletin also includes more limited discussion of Alexandrium spp., the saxitoxin-producing dinoflagellate that causes Paralytic Shellfish Poisoning. The California Harmful Algae Risk Mapping (C-HARM) system creates daily nowcasts and three-day forecasts of DA risk through simulations of the physical circulation using a Regional Ocean Model System (ROMS) to predict water temperature, salinity, upwelling, advection. Quasi-operational, 3-km ROMS output is merged with optical "ocean color" information derived from NASA satellite imagery (MODIS Aqua) to then derive the probability of a toxic HAB event at each pixel. C-HARM is thus a spatially explicit prediction of the risk of Pseudo-nitzschia blooms and DA events. The California Harmful Algal Bloom Monitoring and Alert Program (HABMAP) funded by SCCOOS and CeNCOOS provides a near real-time picture of which HAB species might be blooming in the very nearshore environment. These nearshore data do not always correspond with C-HARM predictions for the open coast. C-HARM output may be more closely correlated with marine mammals that strand along the coast due to "domoic acid toxicosis" (Anderson et al. 2016 Harmful Algae). Maps of DA-related stranding cases reported by six marine animal rescue centers (The Marine Mammal Center, Pacific Marine Mammal Center, Marine Animal Rescue, California Wildlife Center, Marine Mammal Care Center Los Angeles and SeaWorld) are displayed in the bulletin to allow a side-by-side comparison with DA risk predicted by C-HARM. As they are issued, we will provide maps and a quick summary of California Department of Public Health Marine Biotoxin Quarantines and Health Advisories that serve as warnings for recreational seafood harvests, as well as Health Advisories and Closures from the California Department of Fish and Wildlife.

Pseudo-nitzschia Bloom Prediction shows the probability that the abundance of species of the diatom Pseudo-nitzschia in coastal waters is at or above the “bloom” threshold of 10,000 cells per liter.  A value of 0.7, for example, means there’s a 70% predicted probability of Pseudo-nitzschia blooms in that pixel. This threshold is based on work in Trainer and Suddleson 2005, Lane et al. 2009, Anderson et al. 2009, 2011, 2016.

Domoic Acid Event Prediction (for particulate DA) shows the probability that the domoic acid concentration in the bulk phytoplankton pool is at or above 500 nanograms per liter (= 0.5 micrograms per L). A value of 0.7, for example, means there’s a 70% predicted probability of a toxic event, although there is always the possibility that concentrations lower than 500 ng/L will lead to toxins in shellfish or strandings of marine mammals and birds. This threshold is discussed further in Anderson et al. 2009, 2011, 2016.

Domoic AcidToxicity Prediction (for cellular DA) shows the probability that the domoic acid concentration per Pseudo-nitzschia (i.e. how toxic are the algal cells themselves) is at or above 10 picograms per cell (pg/cell). To give a sense of the range, the highest cellular concentrations seen in the environment have not yet exceeded 200 pg/cell in the most toxic cells.  A predicted probability value of 0.7, for example, means there’s a 70% probability that a 10 pg/cell level of toxicity is present in the phytoplankton, although there is always the possibility that concentrations lower than 10 will lead to toxins in shellfish or strandings of marine mammals and birds. This threshold is discussed further in Anderson et al. 2009, 2011, 2016.

Researcher tools for HABs are experiencing a renaissance, and we expect to soon highlight many more observations from technologies such as the Environmental Sample Processor, Imaging Flow CytoBot, and next-generation genetic/'omics analyses, as they become available, to flesh out our view of surface and subsurface HAB activity in coastal California. Through the HAB Bulletin, we will also attempt to highlight information on other potentially harmful phytoplankton, such as Alexandrium spp. (which can cause Paralytic Shellfish Poisoning), Dinophysis (Diarrhetic Shellfish Poisoning), Akashiwo sanguinea, and even the relatively benign "red tides" caused by Lingulodinium polyedra. Future models will incorporate food web effects so that we will be able to provide predictions on specific fisheries and toxin risk.


C-HARM: Clarissa Anderson, Raphe Kudela, Dale Robinson, Fred Bahr, Yi Chao, Henry Ruhl, Yizhen Li, Rick Stumpf (C-HARM is now a product of NOAA Coast Watch in collaboration with NOAA NCCOS)

CeNCOOS: Henry Ruhl, Alex Harper, Fred Bahr, Patrick Daniel

SCCOOS: Clarissa Anderson, Megan Medina, Axiom Data Science

HABMAP PIs: John Largier, Raphael Kudela, G. Jason Smith, Ryan Walter, Alexis Pasulka, Mark Brzezinski, Libe Washburn, Rebecca Shipe, Dave Caron, Melissa Carter

HABMAP Steering Committee: Jayme Smith, Raphe Kudela, Dave Caron, Clarissa Anderson, Bernard Friedman, Vanessa Zubkousky-White, Rick Stumpf, Melissa Carter, Tenaya Norris, Joe Christen, Holly Wyer

CA IFCB Network: Clarissa Anderson, Eric Bjorkstedt, Jeff Abell, John Largier, Raphe Kudela, Henry Ruhl, Francisco Chavez, Bob Miller, Dave Siegel, David Caron, Jayme Smith, George Robertson, Andrew Barton, Jeff Bowman, Uwe Send, and Melissa Carter

California Department of Public Health: Vanessa Zubkowsky-White and Steve Etter

The Marine Mammal Center: Tenaya Norris

Channel Islands Marine Wildlife Institute: Ruth Dover

Pacific Marine Mammal Center: Peter Chang and Michele Hunter

Marine Mammal Care Center of Los Angeles: Lauren Palmer

California Wildlife Center: Jennifer Brent and Heather Henderson

Marine Animal Rescue: Peter Wallerstein, Artie Wong and Brad Torsone

SeaWorld: Jody Westberg and Alexandria Mena

Funding and Support

Funding for development of this Bulletin is provided by NOAA IOOS (SCCOOS Award #NA16NOS0120022, PIs Terrill and Anderson). Funding for C-HARM transition to operations was provided by NASA (NASA ASP Award #80NSSC17K0049, PI Anderson), with sustained support from NOAA NESDIS (West Coast node of CoastWatch) and NOAA NCCOS. HABMAP is supported by NOAA IOOS through grants to SCCOOS (Award #NA16NOS0120022, PI Anderson) and CeNCOOS (Award #NA16NOS012002, PI Ruhl).

We also gratefully acknowledge previous support from California Ocean Protection Council/California Sea Grant (PI Kudela) and from NOAA NCCOS: (ECOHAB #NA11NOS4780030, PI Kudela; MERHAB #NA15NOS4780205, PI Howard; MERHAB #NA04NOS4780239, PI Miller).

CA HAB Bulletin Archive