California HAB Bulletin: September 2021

Pseudo-nitzschia -

C-HARM tells us where conditions are suitable for species of the diatom Pseudo-nitzschia spp. (all size classes) to grow well and where they might be more likely to produce the deadly neurotoxin, domoic acid (DA).
C-HARM predictions in September suggest patchy habitat suitability for Pseudo-nitzschia spp. throughout the state, with a focus on central California and the regions around SF Bay as a particularly intense hotspot.
There was no noteworthy Pseudo-nitzschia presence at any of the HABMAP pier sites where data were reported in September, similar to August.
The Relative Abundance Index (RAI) for the Pseudo-nitzschia "seriata" size class recorded by the California Department of Public Health (CDPH) reached "Common" levels (10-49%) at Scripps Pier in La Jolla, two sites in the Santa Barbara Channel, Pacifica Pier (just outside SF Bay), and Trinidad Pier.
Moderate to very high C-HARM probabilities (50-100%) for particulate domoic acid (pDA) were predicted for large sections of the California coastline in September with three main foci: northern California, central California region near SF and Monterey Bays (except for mid-September when probabilities in this region were very low), and the southern part of the Southern California Bight
The highest probabilities for cellular DA (cDA) formed an obvious bolus in the North Coast region throughout the entire month of September, picking up from where August left off with highest cDA probabilities confined to the North Coast region. This suggests possible issues in that region at the start of Dungeness crab season.
There were only two marine mammal strandings from potential DA toxicosis in September - one mid-month in Los Angeles and one at the end of Sept in Santa Cruz, consistent with very high pDA probabilities in southern California and low probabilities in central California early to mid-month that then reversed pattern later in the month.
HABMAP pDA data are only so far available at Santa Cruz Wharf for the month of September, and no DA was detected, which again underscores the perennial mismatch between the very nearshore measurements at piers and what appears to be occurring offshore based on C-HARM predictions and marine mammal stranding events.
No new shellfish warnings or closures for Amnesic Shellfish Poisoning were added in September

Alexandrium -

CDPH noted that Alexandrium spp. were "Common" in Morro Bay (10% relative abundance index) in September, just as in August and July, suggesting an on-going threat there and consistent with HABMAP sampling at Cal Poly Pier on September 27th. The recreational shellfish advisory related to PSP that was issued for mussels in Marin County (just north of San Francisco) on August 27th is still in effect.

*Please note that HABMAP sampling, CDPH sampling, and marine mammal rescues have been greatly reduced in response to COVID-19 safety measures.

**HABMAP sampling resumed after being suspended in March 2020 in accordance with the Governor's stay at home order. However, COVID-19 safety protocols and sampling restrictions may continue to affect operations and delay results.**

Note that data for some stations are not shown because they are not yet recorded in the public HABMAP archive.

Differentiating Pseudo-nitzschia species by light microscopy is difficult. For this reason, Pseudo-nitzschia "seriata" does not refer to an actual species but rather the larger size class of Pseudo-nitzschia, which is generally a more toxigenic group of species. Alternatively, Pseudo-nitzschia "delicatissima" refers to the smaller size class that is generally non-toxigenic. The dashed line on the plots demarcates the 10,000 cells/L "bloom" threshold designated here for Pseudo-nitzschia populations only.

More information and data visualizations on the statewide HAB network and forecasting system can be found on the California HABMAP website and on the SCCOOS Harmful Algal Bloom page.

CDPH observations for Pseudo-nitzschia "seriata" and Alexandrium spp.

You can view the interactive map and data table of California Department of Public Health (CDPH) data from January 2019 to present, developed by SCCOOS, below. Or, view CDPH Toxic Phytoplankton Observations Map with layers of Pseudo-nitzschia and Alexandrium spp. as well as other phytoplankton species observations (in the pop-up windows).

Data are provided by the Environmental Management Branch of the CDPH. Please note, starting in July 2019, CDPH moved to only reporting Pseudo-nitzschia of the seriata complex and not all Pseudo-nitzschia spp. as previously provided.

Please email CDPH at Susan.Paulukonis@cdph.ca.gov for any potential marine HAB-related illness in humans.

Pseudo-nitzschia "seriata" was detected at "Present" density levels on 26 occasions:

2021-09-01 6% Goleta Pier
2021-09-07 1% Tomales Bay, Lease #M430-15
2021-09-07 3% La Jolla, Scripps Pier
2021-09-07 5% Humboldt Bay, Indian Is. Ch.
2021-09-09 1% Bodega Harbor, USCG Dock
2021-09-09 7% Wilson Creek
2021-09-10 8% Port San Luis, Diablo Cove
2021-09-13 3% Morro Bay, Boat Launch
2021-09-13 7% Humboldt Bay, Indian Is. Ch.
2021-09-14 3% Mendocino, Noyo Harbor
2021-09-15 2% Goleta Pier
2021-09-15 5% Trinidad Pier
2021-09-17 5% Port San Luis, Diablo Cove
2021-09-19 1% Pacifica Pier
2021-09-19 4% GFNMS, Marin Line N11-WN
2021-09-19 4% GFNMS, Marin Line N2WN
2021-09-20 3% Tomales Bay, Lease #M430-15
2021-09-21 1% Santa Cruz Is., Prisoners Hrbr
2021-09-21 5% GFNMS, Marin Line 11E
2021-09-23 5% GFNMS, San Francisco Line 6W
2021-09-23 8% GFNMS, San Francisco Line 6E
2021-09-24 1% Richmond, Marina Bay Harbor
2021-09-24 1% San Simeon Pier
2021-09-24 2% GFNMS, Marin Line N4-WN
2021-09-27 1% Tomales Bay, Lease #M430-15
2021-09-27 4% Humboldt Bay, Indian Is. Ch.

Pseudo-nitzschia "seriata" was detected at "Rare" density levels on 11 occasions:

2021-09-07 0.5% Morro Bay, Boat Launch
2021-09-08 0.5% Ventura, Port Hueneme Pier
2021-09-09 0.5% Ventura, Offshore Station 3
2021-09-11 0.5% San Francisco, Presidio Pier
2021-09-13 0.5% Tomales Bay, Lease #M430-15
2021-09-20 0.5% Humboldt Bay, Indian Is. Ch.
2021-09-20 0.5% Morro Bay, Boat Launch
2021-09-21 0.5% Goleta Pier
2021-09-22 0.5% Monterey Bay, Commercial Wharf
2021-09-27 0.5% Morro Bay, Boat Launch
2021-09-29 0.5% Goleta Pier

Alexandrium spp. were detected at "Rare" density levels on 18 occasions:

2021-09-01 0.5% Goleta Pier
2021-09-06 0.5% Santa Cruz Wharf
2021-09-07 0.5% Humboldt Bay, Indian Is. Ch.
2021-09-08 0.5% Goleta Pier
2021-09-09 0.5% Wilson Creek
2021-09-11 0.5% San Francisco, Presidio Pier
2021-09-13 0.5% Bolinas Lagoon
2021-09-13 0.5% Tomales Bay, Lease #M430-15
2021-09-13 0.5% Morro Bay, Boat Launch
2021-09-15 0.5% Goleta Pier
2021-09-15 0.5% Trinidad Pier
2021-09-18 0.5% GFNMS, Marin Line 2W
2021-09-18 0.5% GFNMS, Marin Line 2E
2021-09-19 0.5% Palos Verdes, OFFSHORE
2021-09-19 0.5% GFNMS, Marin Line N2WN
2021-09-21 0.5% GFNMS, Marin Line 11E
2021-09-22 0.5% Santa Cruz Wharf
2021-09-30 0.5% Ventura, Port Hueneme Pier

CDPH and OEHHA Health Advisories

October 5. The California Department of Public Health (CDPH) has lifted the August 27, 2021 shellfish safety notification related to sport-harvested clams and scallops in Marin County.

August 27. Dangerous levels of paralytic shellfish poisoning (PSP) toxins have been detected in mussels from Marin county.

April 30. The California Department of Public Health (CDPH) announced the annual quarantine of sport-harvested mussels gathered along the California coast.

For the latest closures and updates, please visit the CDPH Health Advisories page as a central location of information related to CDPH health advisories. Also available is a map showing the current CDPH Recreational Bivalve Shellfish Advisories (see below).

NEWS: The HAB-related illness workgroup has developed a new webpage for marine HAB-related illness tracking work (https://oehha.ca.gov/fish/general-info/marine-harmful-algal-bloom-hab-related-illness-tracking).

Domoic acid (DA) is a potent neurotoxin produced by some diatom species of the genus Pseudo-nitzschia. Species exposed to DA can result in seizures, epilepsy, cardiomyopathy, and death depending upon the ingested dose. DA toxicosis commonly occurs in California Sea Lions (Zalophus californianus), presumably due to a combination of foraging behavior and seasonal movements. The Marine Mammal Center (TMMC), Channel Islands Marine Wildlife Institute (CIMWI), California Wildlife Center (CWC), Marine Mammal Care Center Los Angeles (MMCC-LA), Marine Animal Rescue (MAR), the Pacific Marine Mammal Center (PMMC), and SeaWorld act like an emergency room by working to rescue and rehabilitate sick and injured marine mammals, seabirds, and sea turtles.

Among the six rehabilitation centers we received data for in the month of September, 2 marine mammal strandings presented with symptoms of domoic acid toxicosis.

California HAB Bulletin: September 2021

California HAB Bulletin: September 2021

C-HARM Model

Probability of Particulate DA for September 2021

Probability of Cellular DA for September 2021

Probability of Pseudo-nitzschia Bloom for September 2021

Harmful Algal Bloom Monitoring & Alert Program (HABMAP)

Santa Cruz Wharf

Cal Poly Pier

Stearns Wharf

Santa Monica Pier

Newport Beach Pier

Scripps Pier

CDPH observations for Pseudo-nitzschia "seriata" and Alexandrium spp.

Alexandrium spp. were detected in 29 of the 91 samples:

CDPH and OEHHA Health Advisories

California Marine Mammal and Seabird Strandings from Suspected DA Toxicosis

At this time we do not have data from the North Coast Marine Mammal Center.

Contacts if you find a LIVE stranded animal

Contacts if you find a DEAD stranded animal

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