2023 End of Year Report

November 2023 – December 2023

– HAB Bulletin v2 –

The team welcomes any and all feedback on this new format of the California Harmful Algal Bloom bulletin, and extend our gratitude for your continued patience as we work through delays in development & data availability.

C-HARM predictions of particulate domoic acid (pDA) event probability indicate a central and southern California risk that expanded and contracted quite a bit in November and then extended to the nearshore zone of the North Coast in December. Risk of high cellular DA was fairly moderate throughout November, with patches of higher risk in offshore eddies appearing in December for central California.
HABMAP sampling of the plankton at pier sites captured bloom levels of the smaller size class of Pseudo-nitzschia (“delicatissima”) at Newport Beach Pier in November. Pseudo-nitzschia activity was quiescent at all pier sites in December.
CDPH sampling at shore sites detected “common” (moderate) levels of Pseudo-nitzschia “seriata” (the more toxigenic size class) at two sites in November: one in southern California (Los Angeles) and one in central/northern California (Marin). Abundances were low everywhere in December.
IFCB imagery selected for several sites captured a lot of dinoflagellates and is aligned with bioluminescent activity in the southern California region. Classified harmful algal bloom products will appear in the next bulletin!
Domoic acid was detectable but fairly low at several southern and central California HABMAP sites in November and December, indicating some toxin production in those regions. C-HARM predictions of elevated DA risk may be associated with higher production offshore, which is not routinely validated.
However, no marine mammals strandings associated with DA toxicosis were reported for Nov-Dec 2023, indicating no significant DA production or that any potential offshore DA activity was not aligned with marine mammal feeding patterns.
The domoic acid advisory for Del Norte County is still in effect for razor clams, which are known to hold onto toxins for a very long time and are not directly linked to existing blooms.
CDPH lifted the PSP advisory for shellfish in San Luis Obispo County on Dec 12th despite fairly abundant records of Alexandrium spp. at HABMAP sites throughout November and December. CDPH sampling detected only rare or present levels of Alexandrium at sites throughout California, and levels of PSP toxins (e.g. saxitoxin) were sufficiently low in shellfish to lift the advisory.

Summary written by Clarissa Anderson, 26 February 2024

Particulate Domoic Acid

Particulate domoic acid (pDA) is the measurement of total domoic acid toxin that is potentially extant in a given area. This forecast provides a probability for where that concentration of toxin is predicted to exceed the threshold that classifies a Harmful Algal Bloom (> 500 nanograms per liter).

The C-HARM v3 model generates nowcast and forecasts of the probability of Pseudo-nitzschia concentrations of in excess of 10,000 cells/L, the probability of particulate domoic acid > 500 nanograms/L, and the probability of cellular domoic acid > 10 picograms/cell in California and Southern Oregon coastal waters. Inputs for the model include near real-time satellite observations, gap-filled chlorophyll a, 486nm reflectance, and 551nm reflectance fields from the S-NPP NOAA VIIRS sensor plus nowcast and forecast data of surface salinity, sea surface temperature, and surface currents from WCOFS ROMS.

Cellular Domoic Acid

Cellular domoic acid (cDA) is the measure of total domoic acid toxin calculated per cell of Pseudo-Nitzchia. This forecast provides a probability for where those cells are expected to be producing toxin at high levels (> 10 picograms per cell).

The C-HARM v3 model generates nowcast and forecasts of the probability of Pseudo-nitzschia concentrations of in excess of 10,000 cells/L, the probability of particulate domoic acid > 500 nanograms/L, and the probability of cellular domoic acid > 10 picograms/cell in California and Southern Oregon coastal waters. Inputs for the model include near real-time satellite observations, gap-filled chlorophyll a, 486nm reflectance, and 551nm reflectance fields from the S-NPP NOAA VIIRS sensor plus nowcast and forecast data of surface salinity, sea surface temperature, and surface currents from WCOFS ROMS.

Pseudo-nitzschia

Pseudo-nitzschia is a neurotoxin producing diatom that is observed along the California Coast. Blooms of this phytoplankton can be detrimental to surrounding marine ecosystems. This forecast provides a probability for where the concentration of cells in the water exceed the threshold of a Harmful Algal Bloom ( > 10,000 cells/L).

The C-HARM v3 model generates nowcast and forecasts of the probability of Pseudo-nitzschia concentrations of in excess of 10,000 cells/L, the probability of particulate domoic acid > 500 nanograms/L, and the probability of cellular domoic acid > 10 picograms/cell in California and Southern Oregon coastal waters. Inputs for the model include near real-time satellite observations, gap-filled chlorophyll a, 486nm reflectance, and 551nm reflectance fields from the S-NPP NOAA VIIRS sensor plus nowcast and forecast data of surface salinity, sea surface temperature, and surface currents from WCOFS ROMS.

California Harmful Algal Bloom Monitoring & Alert Program

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.

Data for some stations are not shown as they are not yet recorded in the public HABMAP archive.

These time series focus on data collected through the scope of this bulletin and the 12 month period that precedes it. Explore the variables and regions that make up the CalHABMAP collective dataset using the plot controls.

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

Suspect DA Strandings, November-December 2023

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), SeaWorld, and Southwest Fisheries Science Center (SWFSC) act like an emergency room by working to rescue and rehabilitate sick and injured marine mammals, seabirds, and sea turtles.

California's Marine Mammal Stranding Network Map

Each month, water samples are collected by volunteers and sent to the California Department of Public Health (CDPH) for analysis.

The relative abundance of potentially DA-producing Pseudo-nitzschia ‘seriata’ size class and PSP toxin-producing Alexandrium spp. are catalogued:

Water Sample Detailed Data

Date Sampled	County	Sample Site	PN % Comp.	PN Density	AL % Comp.	AL Density
11/1/2023	Los Angeles	Catalina Island, Avalon Bay	2	PRESENT	0.5	RARE
11/1/2023	San Luis Obispo	Port San Luis, Diablo Cove	2	PRESENT	0	ABSENT
11/1/2023	Santa Barbara	Goleta Pier	0	ABSENT	0	ABSENT
11/1/2023	Santa Cruz	Santa Cruz Wharf	0.5	RARE	0	ABSENT
11/2/2023	Los Angeles	Malibu Pier	0	ABSENT	0	ABSENT
11/2/2023	Los Angeles	Catalina Island, Avalon Bay	0	ABSENT	0	ABSENT
11/2/2023	San Francisco	San Francisco, Presidio Pier	0.5	RARE	0	ABSENT
11/3/2023	Los Angeles	Palos Verdes, OFFSHORE	0	ABSENT	0	ABSENT
11/3/2023	Orange	Bolsa Chica	0	ABSENT	0	ABSENT
11/3/2023	Sonoma	Bodega Harbor, USCG Dock	3	PRESENT	0.5	RARE
11/4/2023	Los Angeles	Cabrillo Beach Pier	0	ABSENT	0	ABSENT
11/4/2023	San Francisco	Lake Merritt Boating Center	0	ABSENT	0	ABSENT
11/4/2023	Santa Cruz	Santa Cruz Wharf	0.5	RARE	0	ABSENT
11/6/2023	Humboldt	Humboldt Bay, Indian Is. Ch.	0.5	RARE	0	ABSENT
11/6/2023	Mendocino	Point Arena Pier	0.5	RARE	0.5	RARE
11/6/2023	San Diego	Agua Hedionda Lagoon	0	ABSENT	0	ABSENT
11/6/2023	San Diego	La Jolla, Scripps Pier	1	PRESENT	0.5	RARE
11/6/2023	San Luis Obispo	Morro Bay, Boat Launch	0.5	RARE	0.5	RARE
11/7/2023	Humboldt	Trinidad Pier	0.5	RARE	0	ABSENT
11/7/2023	Los Angeles	Santa Monica Pier	0	ABSENT	0	ABSENT
11/7/2023	San Mateo	Bean Hollow State Beach	0	ABSENT	0	ABSENT
11/7/2023	San Mateo	Pillar Point	0.5	RARE	0	ABSENT
11/8/2023	Los Angeles	Catalina Island, Toyon Bay	0	ABSENT	0	ABSENT
11/8/2023	Marin	Drakes Bay, Chimney Rock LBS	4	PRESENT	0	ABSENT
11/8/2023	Mendocino	Mendocino, Noyo Harbor	0	ABSENT	0	ABSENT
11/8/2023	San Diego	Imperial Beach Pier	0	ABSENT	0	ABSENT
11/8/2023	Santa Barbara	Goleta Pier	2	PRESENT	0	ABSENT
11/8/2023	Santa Cruz	Santa Cruz Wharf	0	ABSENT	0	ABSENT
11/9/2023	Marin	Richmond, Marina Bay Harbor	0	ABSENT	0	ABSENT
11/10/2023	Orange	Bolsa Chica	2	PRESENT	0	ABSENT
11/10/2023	San Diego	Imperial Beach Pier	0.5	RARE	0	ABSENT
11/11/2023	Los Angeles	Palos Verdes, OFFSHORE	0	ABSENT	0	ABSENT
11/11/2023	Los Angeles	Los Angeles, Terminal Island	0	ABSENT	0	ABSENT
11/11/2023	San Francisco	Lake Merritt Boating Center	0	ABSENT	0	ABSENT
11/12/2023	Los Angeles	Point Dume, offshore	0	ABSENT	0	ABSENT
11/12/2023	Los Angeles	Catalina Island, Avalon Bay	0	ABSENT	0	ABSENT
11/12/2023	San Diego	Pacific Beach Pier	0	ABSENT	0	ABSENT
11/13/2023	Humboldt	Humboldt Bay, Indian Is. Ch.	1	PRESENT	0	ABSENT
11/13/2023	Marin	Tomales Bay, Lease #M430-15	0.5	RARE	0	ABSENT
11/13/2023	Marin	Tomales Bay, Lease #M430-15	10	COMMON	0	ABSENT
11/13/2023	San Diego	Agua Hedionda Lagoon	0	ABSENT	0	ABSENT
11/13/2023	San Diego	La Jolla, Scripps Pier	0	ABSENT	0	ABSENT
11/13/2023	San Luis Obispo	Morro Bay, Boat Launch	0.5	RARE	0	ABSENT
11/14/2023	Mendocino	Mendocino, Noyo Harbor	1	PRESENT	0	ABSENT
11/14/2023	San Luis Obispo	San Luis Obispo, Cal Poly Pier	0.5	RARE	0.5	RARE
11/14/2023	Santa Barbara	Santa Cruz Is., Prisoners Hrbr	0.5	RARE	0	ABSENT
11/14/2023	Santa Barbara	Goleta Pier	0	ABSENT	0	ABSENT
11/15/2023	San Francisco	San Francisco, Presidio Pier	0.5	RARE	0	ABSENT
11/15/2023	Santa Cruz	Santa Cruz Wharf	0	ABSENT	0	ABSENT
11/16/2023	Orange	San Clemente Pier	0	ABSENT	0	ABSENT
11/17/2023	Los Angeles	Palos Verdes Rocky Pt Offshore	0	ABSENT	0	ABSENT
11/17/2023	Orange	Bolsa Chica	0	ABSENT	0	ABSENT
11/18/2023	Santa Barbara	Goleta Pier	3	PRESENT	0	ABSENT
11/19/2023	San Luis Obispo	Cayucos Pier	0	ABSENT	0	ABSENT
11/20/2023	Humboldt	Humboldt Bay, Indian Is. Ch.	0	ABSENT	0	ABSENT
11/20/2023	Los Angeles	Catalina Island, Toyon Bay	12	COMMON	0	ABSENT
11/20/2023	Marin	Tomales Bay, Lease #M430-15	0	ABSENT	3	PRESENT
11/20/2023	Monterey	Monterey Bay, Commercial Wharf	4	PRESENT	0	ABSENT
11/20/2023	San Diego	La Jolla, Scripps Pier	0.5	RARE	0.5	RARE
11/20/2023	San Diego	Agua Hedionda Lagoon	0	ABSENT	0	ABSENT
11/20/2023	San Luis Obispo	Morro Bay, Boat Launch	1	PRESENT	0	ABSENT
11/20/2023	Santa Barbara	Goleta Pier	0.5	RARE	0	ABSENT
11/21/2023	Los Angeles	Santa Monica Pier	2	PRESENT	0	ABSENT
11/21/2023	San Diego	Imperial Beach Pier	0.5	RARE	0	ABSENT
11/21/2023	San Diego	San Diego Bay, U.S. Navy Pier	0	ABSENT	0	ABSENT
11/21/2023	Santa Barbara	Santa Barbara Ch., Naples Pt	0	ABSENT	0	ABSENT
11/21/2023	Santa Barbara	Santa Barbara, Mohawk Reef	0	ABSENT	0	ABSENT
11/22/2023	San Luis Obispo	Port San Luis, Diablo Cove	0.5	RARE	0.5	RARE
11/22/2023	Santa Cruz	Santa Cruz Wharf	0	ABSENT	0.5	RARE
11/24/2023	Los Angeles	Catalina Island, Avalon Bay	0	ABSENT	0	ABSENT
11/24/2023	Orange	Bolsa Chica	0	ABSENT	0	ABSENT
11/25/2023	Los Angeles	Cabrillo Beach	0	ABSENT	0	ABSENT
11/25/2023	San Francisco	Lake Merritt Boating Center	0	ABSENT	0	ABSENT
11/26/2023	Los Angeles	Palos Verdes Rocky Pt Offshore	0	ABSENT	0	ABSENT
11/26/2023	Sonoma	Kashia Coastal Reserve	0	ABSENT	0.5	RARE
11/27/2023	Del Norte	Hidden Beach	0	ABSENT	0	ABSENT
11/27/2023	Humboldt	Humboldt Bay, Indian Is. Ch.	0	ABSENT	0	ABSENT
11/27/2023	Marin	Tomales Bay, Lease #M430-15	1	PRESENT	1.5	PRESENT
11/27/2023	San Diego	Agua Hedionda Lagoon	0	ABSENT	0	ABSENT
11/27/2023	San Diego	La Jolla, Scripps Pier	0	ABSENT	0	ABSENT
11/27/2023	San Diego	La Jolla, Scripps Pier	1.5	PRESENT	0	ABSENT
11/27/2023	San Luis Obispo	Morro Bay, Boat Launch	0	ABSENT	0.5	RARE
11/28/2023	Los Angeles	Manhattan Beach Pier	0.5	RARE	0	ABSENT
11/28/2023	Mendocino	Mendocino, Noyo Harbor	0.5	RARE	0	ABSENT
11/28/2023	San Luis Obispo	Port San Luis, Diablo Cove	0.5	RARE	0.5	RARE
11/28/2023	Sonoma	Bodega Harbor, USCG Dock	0.5	RARE	2	PRESENT
11/29/2023	Del Norte	Hunter Rock, north	0	ABSENT	0	ABSENT
11/29/2023	Orange	San Clemente Pier	0	ABSENT	0	ABSENT
11/29/2023	San Diego	Imperial Beach Pier	0.5	RARE	0	ABSENT
11/29/2023	San Francisco	Lake Merritt Boating Center	0	ABSENT	0	ABSENT
11/29/2023	Santa Cruz	Santa Cruz Wharf	0	ABSENT	0	ABSENT
11/30/2023	Marin	Richmond Breakwater	0	ABSENT	0	ABSENT
11/30/2023	Orange	Bolsa Chica	0	ABSENT	0	ABSENT
12/4/2023	Humboldt	Humboldt Bay, Indian Is. Ch.	0	ABSENT	0	ABSENT
12/4/2023	Los Angeles	Santa Monica Pier	0	ABSENT	0	ABSENT
12/4/2023	Marin	Tomales Bay, Lease #M430-15	0	ABSENT	2	PRESENT
12/4/2023	San Diego	La Jolla, Scripps Pier	0.5	RARE	0.2	RARE
12/4/2023	San Luis Obispo	Morro Bay, Boat Launch	0.5	RARE	0	ABSENT
12/5/2023	Los Angeles	Santa Monica Bay, 3901	0	ABSENT	0	ABSENT
12/5/2023	Mendocino	Point Arena Pier	0	ABSENT	0.5	RARE
12/5/2023	Santa Barbara	Goleta Pier	0.5	RARE	0	ABSENT
12/6/2023	San Diego	Agua Hedionda Lagoon	0	ABSENT	0	ABSENT
12/6/2023	Santa Cruz	Santa Cruz Wharf	0.5	RARE	0.5	RARE
12/7/2023	Los Angeles	Santa Monica Bay, 3201	0	ABSENT	0	ABSENT
12/7/2023	San Diego	San Diego Bay, U.S. Navy Pier	3	PRESENT	0	ABSENT
12/8/2023	Orange	Bolsa Chica	0	ABSENT	0	ABSENT
12/8/2023	San Francisco	San Francisco, Presidio Pier	0	ABSENT	0	ABSENT
12/9/2023	San Francisco	Lake Merritt Boating Center	0	ABSENT	0	ABSENT
12/10/2023	Los Angeles	Palos Verdes Rocky Pt Offshore	0	ABSENT	0	ABSENT
12/11/2023	Humboldt	Humboldt Bay, Indian Is. Ch.	0	ABSENT	0	ABSENT
12/11/2023	Marin	Tomales Bay, Lease #M430-15	0.5	RARE	0	ABSENT
12/11/2023	San Diego	Agua Hedionda Lagoon	0	ABSENT	0	ABSENT
12/11/2023	San Luis Obispo	Morro Bay, Boat Launch	0.5	RARE	0	ABSENT
12/12/2023	Mendocino	Mendocino, Noyo Harbor	0.5	RARE	0	ABSENT
12/12/2023	San Mateo	Bean Hollow State Beach	0	ABSENT	0	ABSENT
12/12/2023	San Mateo	Pillar Point Harbor	0	ABSENT	0	ABSENT
12/13/2023	Marin	Richmond, Marina Bay Harbor	0	ABSENT	0	ABSENT
12/13/2023	Monterey	Monterey Bay, Commercial Wharf	0	ABSENT	0.5	RARE
12/13/2023	San Luis Obispo	Cayucos Pier	0.5	RARE	0	ABSENT
12/13/2023	Santa Barbara	Goleta Pier	0.5	RARE	0	ABSENT
12/13/2023	Santa Cruz	Santa Cruz, Capitola Pier	0	ABSENT	0	ABSENT
12/13/2023	Sonoma	Bodega Harbor, USCG Dock	0.5	RARE	0.5	RARE
12/14/2023	San Diego	San Diego Bay, U.S. Navy Pier	0	ABSENT	0	ABSENT
12/15/2023	Orange	Dana Pt. Harbor	0	ABSENT	0	ABSENT
12/15/2023	Orange	Bolsa Chica	0	ABSENT	0	ABSENT
12/15/2023	San Luis Obispo	Port San Luis, Diablo Cove	0	ABSENT	0	ABSENT
12/16/2023	Los Angeles	Point Dume, offshore	0	ABSENT	0	ABSENT
12/18/2023	Humboldt	Humboldt Bay, Indian Is. Ch.	0	ABSENT	0	ABSENT
12/18/2023	San Diego	Agua Hedionda Lagoon	0	ABSENT	0	ABSENT
12/18/2023	San Diego	Pacific Beach Pier	0	ABSENT	0	ABSENT
12/18/2023	San Diego	La Jolla, Scripps Pier	0	ABSENT	1	PRESENT
12/18/2023	San Luis Obispo	Morro Bay, Boat Launch	3	PRESENT	0.5	RARE
12/19/2023	Marin	Tomales Bay, Lease #M430-15	0.5	RARE	0	ABSENT
12/20/2023	San Diego	San Diego Bay, U.S. Navy Pier	0	ABSENT	0	ABSENT
12/20/2023	Santa Cruz	Santa Cruz, Capitola Pier	0	ABSENT	0	ABSENT
12/21/2023	Humboldt	Trinidad Pier	0	ABSENT	0	ABSENT
12/21/2023	San Mateo	Bean Hollow State Beach	0	ABSENT	0	ABSENT
12/21/2023	San Mateo	Pillar Point Harbor	0	ABSENT	0	ABSENT
12/22/2023	Orange	Bolsa Chica	0	ABSENT	0	ABSENT
12/26/2023	Marin	Tomales Bay, Lease #M430-15	1	PRESENT	0	ABSENT
12/26/2023	San Diego	Agua Hedionda Lagoon	0	ABSENT	0	ABSENT
12/27/2023	San Diego	Imperial Beach Pier	0.5	RARE	0	ABSENT
12/28/2023	Marin	Drakes Bay, Chimney Rock LBS	0	ABSENT	0	ABSENT
12/29/2023	Orange	Bolsa Chica	0	ABSENT	0	ABSENT

Percent composition categories help us look at phytoplankton trends across an entire region to evaluate risk of biotoxin presence. Many other factors contribute to our evaluation of risk in an area. These samples are posted for informational purposes only. They are not intended to inform the public of the presence or lack of risk. For the latest health advisory information, see the CDPH Health Advisory Map below.

A network of Imaging FlowCytobots (IFCBs) continuously photographs particles, such as plankton, in the water. Using machine learning, plankton species can be automatically identified. This will help improve the ability to detect and respond to Harmful Algal Blooms, including the ability to assess conditions that may lead to toxin production or blooms of toxin-producing algae.

Additional images and data are available on the IFCB dashboard.