info@sccoos.org
Summer 2025: July, August, September
Summary written by Dr. Kasia Kenitz & Dr. Clarissa Anderson on October 28, 2025
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- SUMMARY: Following the decline of the spring domoic acid (DA) event, harmful algal bloom (HAB) activity varied along the California coast from July through September. While Southern California remained dominated by mostly harmless dinoflagellates such as Akashiwo and Prorocentrum, Central California experienced elevated Pseudo-nitzschia activity both nearshore and offshore. A particularly intense bloom was observed at Santa Cruz Municipal Wharf in mid-July, where P. nitzschia (primarily of the “delicatissima” size class) reached an exceptional 19 million cells/L, coinciding with elevated particulate DA concentrations. Elevated abudnances of Pseudo-nitzschia “delicatissima” group were also observed at Monterey Wharf and at Cal Poly Pier in July and August. The more toxigenic P. “seriata” group was elevated at Monterey Bay and Cal Poly Pier in early August, and Cal Poly Pier also recorded elevated particulate domoic acid at that time. Notably, Pseudo-nitzschia abundances declined substantially across coastal sites by September. Offshore persistence of Pseudo-nitzschia was documented by early August and late September research cruises, which detected concerning abundances offshore in Santa Barbara Channel and in Central California, where Pseudo-nitzschia populations extended as far north as Point Arena. Marine mammal strandings suspected to be associated with DA exposure remained very low, however – only seven suspect DA strandings reported statewide since July – consistent with generally low coastal pDA and Pseudo-nitzschia activity at coastal monitoring sites but inconsistent with offshore bloom levels in mid-to-late summer. A concerning persistence of very high abundances of Alexandrium offshore should be watched closely given the chance of developing cyst beds on the shelf that might lead to a recurring issue with Alexandrium and PSP risk.
- C-HARM model predictions continue to indicate high risk for toxic Pseudo-nitzschia spp. bloom development along the entire California coast, encompassing both nearshore and offshore regions. By the end of July, the probability of alert-level particulate domoic acid (pDA) in Southern California declines, only to increase again by late August and throughout much of September, with high probabilities reported across both coastal and offshore zones. Elevated pDA probabilities persist through July around the Channel Islands and Central California. During August and September, certain coastal areas in Central California periodically exhibit reduced probabilities of alert-level pDA, while elevated risk remains offshore. High probabilities of bloom-level abundances of Pseudo-nitzschia are predicted along much of the California coastline from July through September. In the Southern California Bight, localized patches of elevated bloom probability appear along the coast, whereas offshore areas show near-zero probabilities of high Pseudo-nitzschia abundances. Similarly, near-zero risk predictions for cellular domoic acid (cDA) across most nearshore and offshore regions of Southern California suggest that any coastal blooms in this region are unlikely to be toxigenic. In contrast, the Channel Islands and both nearshore and offshore areas of Central and Northern California remain high-risk regions for the development of toxic Pseudo-nitzschia blooms throughout July to September. These areas consistently show elevated probabilities for both high Pseudo-nitzschia abundances and cDA, with notable hotspots near Monterey, Santa Cruz, and across much of the Northern California coast in July. Although the risk of high cellular DA remains elevated in August and September, it is generally lower than the risk levels observed in July. Overall, C-HARM predictions are broadly consistent with observations, which indicate high Pseudo-nitzschia and DA risk in Central California in July, low to non-detectable Pseudo-nitzschia abundances at coastal monitoring stations along the California coast in August September, but sustained high abundances offshore, as reported by offshore cruises in Central California.
- Weekly HABMAP sampling of phytoplankton exceptionally high abundances of the less toxigenic Pseudo-nitzschia “delicatissima” group in Central California during July, particularly at Santa Cruz Municipal Wharf. On July 16, P. nitzschia reached a striking 19 million cells/L — one of the highest concentrations recorded this season, if not ever — dominated by the “delicatissima” size class. This bloom coincided with a notable increase in particulate domoic acid (pDA) concentrations at the site (1.79 ng/L). As reported by the Kudela lab, “At the levels observed in the lab, this bloom would have exceeded the toxin thresholds used in NOAA’s C-HARM model by nearly twofold, while cell counts surpassed the model’s waring threshold over 400 times. This finding raises important questions about overlooked Pseudo-nitzschia species and their potential to cause ecological and public health impacts.” Pseudo-nitzschia remained abundant through late July before declining to “common” levels in August and disappearing completely by the end of September. Elsewhere in Central California, elevated Pseudo-nitzschia abundances were also observed at Monterey Wharf on July 23 (2,164,000 cells/L) and at Cal Poly Pier in early and mid-August (858,000 cells/L on August 4 and 930,000 cells/L on August 18). The more toxigenic Pseudo-nitzschia “seriata” group reached peak concentrations in the first half of August, exceeding 57,000 cells/L at both Cal Poly Pier and Monterey Bay, and coinciding with elevated pDA concentrations at Cal Poly Pier (0.71 ng/L on August 4). Pseudo-nitzschia abundances declined substantially across coastal sites by September. No pDA was detected in seawater samples collected between July and September at Southern California sites: SIO Pier, Santa Monica Pier, or Stearns Wharf. Although concerning Pseudo-nitzschia abundances were not observed at Stearns Wharf in Santa Barbara since early May, during a UCSB research cruise (August 5, 2025) aboard the R/V Shearwater, offshore samples showed abundances of 80,000 cells/L for Pseudo-nitzschia “delicatissima” and 75,000 cells/L for Pseudo-nitzschia “seriata” – levels considered concerning and indicating that the bloom persisted offshore. A subsequent research cruise in late September, spanning Central to Northern California, confirmed that offshore <em”>Pseudo-nitzschia populations extended as far north as Point Arena, with elevated abundances also detected in Monterey Bay. It is important to note that alongside the Pseudo-nitzschia bloom at Cal Poly Pier, very high and concerning abundances of Alexandrium were also recorded throughout much of August, peaking at 39,981 cells/L on August 4. Alexandrium abundances increased again toward the end of September, reaching 40,514 cells/L, which is reaching new records for many places in coastal California and should continue to be looked at carefully with both shore station and offshore sampling!
- The Imaging Flow Cytobots (IFCBs) — robotic microscopes recording hourly observations at the same piers and on two moorings out on the shelf — typically corroborate HABMAP observations and offer detailed insight into HAB community dynamics. However, this summer the IFCBs continued to underdetect Pseudo-nitzschia, failing to capture the the intense July bloom of P. nitzschia observed by HABMAP at Santa Cruz and Monterey Bay. In contrast, IFCB data remained consistent with HABMAP in showing the dominance of Akashiwo and Prorocentrum along much of the coast. There is no IFCB deployed at Cal Poly Pier, so direct comparison with HABMAP data there is not possible. In Monterey Bay, the IFCB deployed on the offshore M1 Power Buoy detected elevated Pseudo-nitzschia abundances, recording up to 8,000 chains/L in mid-August. However, these levels were overshadowed by concurrent nearshore blooms of Akashiwo sanguinea and Prorocentrum spp. Contrary to the late September cruise observations, which reported the subsurface chlorophyll maximum to be dominated by Pseudo-nitzschia and Akashiwo populations in Monterey Bay, the offshore IFCB on the M1 Power Buoy did not detect Pseudo-nitzschia. This mismatch is likely due to differences in sampling depth: IFCB samples are collected at the surface, whereas cruise samples were taken from the chlorophyll maximum ~30-35 feet below the surface. Overall, IFCB data confirm that coastal HAB communities were overwhelmingly dominated by Akashiwo and/or Prorocentrum from July through September, corroborating HABMAP reports from coastal stations.
- Marine Mammal Strandings continued to drop, with only 7 suspect DA sea lion strandings reported for the entire California coast since July 2025. These more recent DA strandings are suspected to be chronically impacted sea lions with permanent brain damage as a result of past bloom events. The lack of acute DA cases is in general agreement with a low Pseudo-nitzschia activity observed at the HABMAP and IFCB coastal sampling stations, and a low DA levels recorded at the coast.
- California Department of Public Health (CDPH) conducts its own phytoplankton monitoring and shellfish and seafood testing for PSP toxins and DA. CDPH monitoring detected Pseudo-nitzschia at common levels (>10% of the phytoplankton community) at San Luis Obispo and Morro Bay, as well as at several Northern California sites, including Point Arena, Mendocino, and Humboldt Bay. In contrast, most Southern California sites showed only rare to present levels (<1%), consistent with HABMAP and IFCB data. The highest proportion of Alexandrium along the California coast was observed at San Luis Obispo, where it contributed approximately 5% to the plankton community, consistent with HABMAP and offshore observations. Elevated PSP toxin levels (256 µg/100 g) were detected in mussels collected from the Cal Poly Pier on August 26, followed by moderate levels (70 µg/100 g) on September 8. A recreational shellfish advisory was in effect and lifted on September 30. No alert-level concentrations of PSP or DA toxins were detected along the coast during September and October.
- Currently, CDPH is advising the public not to consume sport-harvested mussels, clams, scallops, or oysters from the Northern Channel Islands and razor clams from Humboldt County, due to elevated DA levels detected in shellfish in those areas. In addition, a statewide mussel quarantine is in effect annually from May 1 through October 31.
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 v4 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-nitzschia. 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 v4 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 v4 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
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.
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.
These data, coupled with the image classification algorithms developed in collaboration with SCCOOS and CeNCOOS, allow for estimates of species composition over time. The time series below depict sampling outcomes across several California sites. Support provided by NOAA IOOS and CA OPC.
Additional images and data are available on the IFCB dashboard.
Each month, water samples are collected by volunteers and sent to the California Department of Public Health (CDPH) for analysis. The relative abundance of DA-producing Pseudo-nitzschia ‘seriata’ size class (upper) and PSP toxin-producing Alexandrium spp. (lower) are catalogued from sample locations within each county.
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.
Water Sample Detailed Data
| Date_Sampled | County | Sample_Site | PN_Percent_Comp | PN_Density | AL_Percent_Comp | AL_Density |
|---|---|---|---|---|---|---|
| 2025-07-01 | Ventura | Ventura, Port Hueneme Pier | 3 | PRESENT | 0 | ABSENT |
| 2025-07-07 | Humboldt | Humboldt Bay, Indian Is. Ch. | 0 | ABSENT | 0.5 | RARE |
| 2025-07-07 | San Luis Obispo | Morro Bay, Boat Launch | 0.5 | RARE | 0.5 | RARE |
| 2025-07-07 | Marin | Tomales Bay, Lease #M430-15 | 1 | PRESENT | 0 | ABSENT |
| 2025-07-02 | Santa Barbara | Goleta Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-07-09 | Humboldt | Trinidad Pier | 0 | ABSENT | 0.5 | RARE |
| 2025-07-04 | San Francisco | San Francisco, Presidio Pier | 0.5 | RARE | 4 | PRESENT |
| 2025-07-16 | Santa Cruz | Santa Cruz Wharf | 0 | ABSENT | 5 | PRESENT |
| 2025-07-21 | Marin | Tomales Bay, Lease #M430-15 | 0.5 | RARE | 0 | ABSENT |
| 2025-07-16 | Santa Barbara | Goleta Pier | 0.5 | RARE | 0.5 | RARE |
| 2025-07-21 | San Luis Obispo | Morro Bay, Boat Launch | 0 | ABSENT | 0 | ABSENT |
| 2025-07-22 | Marin | Drakes Bay, Chimney Rock LBS | 0 | ABSENT | 0 | ABSENT |
| 2025-07-09 | Santa Cruz | Santa Cruz Wharf | 1 | PRESENT | 0 | ABSENT |
| 2025-07-14 | Marin | Tomales Bay, Lease #M430-15 | 3 | PRESENT | 0 | ABSENT |
| 2025-07-14 | San Luis Obispo | Morro Bay, Boat Launch | 0.5 | RARE | 0 | ABSENT |
| 2025-07-14 | Humboldt | Humboldt Bay, Indian Is. Ch. | 0 | ABSENT | 0 | ABSENT |
| 2025-07-02 | San Diego | Oceanside Harbor | 15 | COMMON | 0 | ABSENT |
| 2025-07-02 | Mendocino | Mendocino, Noyo Harbor | 0 | ABSENT | 0 | ABSENT |
| 2025-07-14 | Sonoma | Bodega Harbor, USCG Dock | 4 | PRESENT | 0 | ABSENT |
| 2025-07-11 | San Mateo | Pacifica, Mori Point | 0 | ABSENT | 4 | PRESENT |
| 2025-07-02 | Orange | Newport Bay, Back Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-07-03 | San Diego | Imperial Beach Pier | 8 | PRESENT | 0 | ABSENT |
| 2025-07-02 | Santa Cruz | Santa Cruz Wharf | 20 | COMMON | 0 | ABSENT |
| 2025-07-03 | San Diego | San Diego Bay, U.S. Navy Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-07-03 | Orange | Bolsa Chica | 2 | PRESENT | 0 | ABSENT |
| 2025-07-04 | San Mateo | GFNMS, San Mateo Line 23W | 20 | COMMON | 0.5 | RARE |
| 2025-07-28 | Humboldt | Humboldt Bay, Indian Is. Ch. | 0 | ABSENT | 0.5 | RARE |
| 2025-07-08 | Orange | Newport Bay, Back Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-07-11 | Santa Barbara | Santa Barbara Ch., Naples Pt | 1 | PRESENT | 0 | ABSENT |
| 2025-07-14 | Del Norte | Hunter Rock, north | 0 | ABSENT | 0 | ABSENT |
| 2025-07-08 | San Diego | Pacific Beach Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-07-11 | Orange | Bolsa Chica | 5 | PRESENT | 0 | ABSENT |
| 2025-07-08 | Orange | Dana Pt. Harbor | 0 | ABSENT | 0 | ABSENT |
| 2025-07-24 | San Luis Obispo | San Luis Obispo, Cal Poly Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-07-24 | San Luis Obispo | Cayucos Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-07-22 | Del Norte | Hunter Rock, north | 0.5 | RARE | 0 | ABSENT |
| 2025-07-13 | Los Angeles | Palos Verdes Rocky Pt Offshore | 0.5 | RARE | 0 | ABSENT |
| 2025-07-14 | Sonoma | Kashia Coastal Reserve | 2 | PRESENT | 0 | ABSENT |
| 2025-07-15 | Sonoma | Shell Beach, Sea Ranch | 3 | PRESENT | 0 | ABSENT |
| 2025-07-15 | Del Norte | Hidden Beach | 0.5 | RARE | 0.5 | RARE |
| 2025-07-07 | San Diego | La Jolla, Scripps Pier | 5 | PRESENT | 0 | ABSENT |
| 2025-07-07 | Los Angeles | Palos Verdes, OFFSHORE | 0.5 | RARE | 0 | ABSENT |
| 2025-07-22 | Sonoma | Sea Ranch | 0.5 | RARE | 0 | ABSENT |
| 2025-07-21 | Mendocino | Point Arena Pier | 1 | PRESENT | 0 | ABSENT |
| 2025-07-16 | San Mateo | Pillar Point Harbor | 0 | ABSENT | 0 | ABSENT |
| 2025-07-23 | Santa Cruz | Santa Cruz Wharf | 0.5 | RARE | 0.5 | RARE |
| 2025-07-04 | Los Angeles | Palos Verdes, OFFSHORE | 0 | ABSENT | 0 | ABSENT |
| 2025-07-01 | San Luis Obispo | Port San Luis, Diablo Cove | 0 | ABSENT | 0.5 | RARE |
| 2025-07-05 | Los Angeles | Palos Verdes, OFFSHORE | 2 | PRESENT | 0 | ABSENT |
| 2025-07-07 | Los Angeles | Redondo Beach Pier | 0.5 | RARE | 0 | ABSENT |
| 2025-07-11 | Santa Barbara | Santa Barbara, Mohawk Reef | 0.5 | RARE | 0 | ABSENT |
| 2025-07-15 | Mendocino | Mendocino, Noyo Harbor | 5 | PRESENT | 0 | ABSENT |
| 2025-07-17 | San Luis Obispo | Cayucos Pier | 0.5 | RARE | 0 | ABSENT |
| 2025-07-17 | Orange | San Clemente Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-07-18 | San Diego | San Diego Bay, U.S. Navy Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-07-19 | San Luis Obispo | San Simeon Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-07-28 | San Luis Obispo | Morro Bay, Boat Launch | 0.5 | RARE | 0 | ABSENT |
| 2025-07-06 | San Luis Obispo | San Simeon Pier | 0 | ABSENT | 0.5 | RARE |
| 2025-07-20 | Del Norte | Wilson Creek | 0.5 | RARE | 0 | ABSENT |
| 2025-07-09 | San Diego | Imperial Beach Pier | 6 | PRESENT | 0 | ABSENT |
| 2025-07-10 | San Diego | San Diego Bay, U.S. Navy Pier | 1 | PRESENT | 0 | ABSENT |
| 2025-07-16 | San Luis Obispo | Port San Luis, Diablo Cove | 0.5 | RARE | 0.5 | RARE |
| 2025-07-11 | San Francisco | San Francisco, Presidio Pier | 0.5 | RARE | 0.5 | RARE |
| 2025-07-03 | Santa Cruz | GFNMS, Santa Cruz Line 27E | 10 | COMMON | 1 | PRESENT |
| 2025-07-05 | San Mateo | GFNMS, San Mateo Line N10-WN | 4 | PRESENT | 1 | PRESENT |
| 2025-07-07 | Sonoma | GFNMS, Sonoma Line 13E | 3 | PRESENT | 0 | ABSENT |
| 2025-07-01 | Marin | GFNMS, San Francisco Line 6E | 5 | PRESENT | 0 | ABSENT |
| 2025-07-18 | San Francisco | San Francisco, Presidio Pier | 0.5 | RARE | 0 | ABSENT |
| 2025-07-15 | Orange | Newport Bay, Back Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-07-17 | Los Angeles | Palos Verdes Rocky Pt Offshore | 5 | PRESENT | 0 | ABSENT |
| 2025-07-21 | Del Norte | Wilson Creek | 0 | ABSENT | 0 | ABSENT |
| 2025-07-28 | Marin | Tomales Bay, Lease #M430-15 | 0 | ABSENT | 0 | ABSENT |
| 2025-07-08 | Sonoma | GFNMS, Sonoma Line N15-EN | 0.5 | RARE | 0 | ABSENT |
| 2025-07-24 | San Diego | Pacific Beach Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-07-14 | San Diego | La Jolla, Scripps Pier | 3 | PRESENT | 0.5 | RARE |
| 2025-07-21 | San Diego | La Jolla, Scripps Pier | 0.5 | RARE | 0.5 | RARE |
| 2025-07-18 | Orange | Bolsa Chica | 0 | ABSENT | 0 | ABSENT |
| 2025-07-07 | Sonoma | GFNMS, Sonoma Line 13M | 1 | PRESENT | 0 | ABSENT |
| 2025-07-08 | Sonoma | GFNMS, Sonoma Line 15M | 1 | PRESENT | 0 | ABSENT |
| 2025-07-09 | Marin | GFNMS, Marin Line N2WN | 0.5 | RARE | 0 | ABSENT |
| 2025-07-07 | Sonoma | GFNMS, Sonoma Line N13-WN | 6 | PRESENT | 0 | ABSENT |
| 2025-07-10 | Del Norte | Wilson Creek | 0.5 | RARE | 0.5 | RARE |
| 2025-07-08 | Sonoma | GFNMS, Sonoma Line 15-E | 1 | PRESENT | 0 | ABSENT |
| 2025-07-05 | San Mateo | GFNMS, San Mateo Line 10E | 2 | PRESENT | 0.5 | RARE |
| 2025-07-27 | Humboldt | Trinidad Pier | 4 | PRESENT | 5 | PRESENT |
| 2025-07-29 | Los Angeles | Santa Monica Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-07-30 | Mendocino | Mendocino, Noyo Harbor | 0.5 | RARE | 0 | ABSENT |
| 2025-07-30 | San Diego | San Diego Bay, U.S. Navy Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-07-25 | San Diego | San Diego Bay, U.S. Navy Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-07-26 | San Luis Obispo | Cayucos Pier | 0 | ABSENT | 0.5 | RARE |
| 2025-07-30 | San Diego | Imperial Beach Pier | 3 | PRESENT | 0 | ABSENT |
| 2025-07-22 | Orange | Newport Bay, Back Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-07-25 | San Francisco | San Francisco, Presidio Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-07-28 | San Diego | La Jolla, Scripps Pier | 0 | ABSENT | 0.5 | RARE |
| 2025-07-02 | San Mateo | GFNMS, Santa Cruz Line 24E | 20 | COMMON | 0.5 | RARE |
| 2025-07-18 | Mendocino | Mendocino, Noyo OFFSHORE | 3 | PRESENT | 0 | ABSENT |
| 2025-07-22 | Los Angeles | Santa Monica Pier | 0 | ABSENT | 0.5 | RARE |
| 2025-07-25 | Los Angeles | Palos Verdes Rocky Pt Offshore | 0 | ABSENT | 0 | ABSENT |
| 2025-07-25 | Orange | Bolsa Chica | 0 | ABSENT | 0.5 | RARE |
| 2025-07-28 | San Diego | Imperial Beach Pier | 0 | ABSENT | 0.5 | RARE |
| 2025-07-22 | Los Angeles | Palos Verdes, OFFSHORE | 0.5 | RARE | 0 | ABSENT |
| 2025-07-25 | Mendocino | Mendocino, Noyo Harbor | 7 | PRESENT | 0 | ABSENT |
| 2025-07-30 | Santa Barbara | Goleta Pier | 0.5 | RARE | 0 | ABSENT |
| 2025-07-24 | San Diego | Imperial Beach Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-07-29 | San Mateo | Bean Hollow State Beach | 0 | ABSENT | 0 | ABSENT |
| 2025-07-29 | San Mateo | Pillar Point Harbor | 0 | ABSENT | 0 | ABSENT |
| 2025-07-30 | Santa Cruz | Santa Cruz Wharf | 0 | ABSENT | 0 | ABSENT |
| 2025-07-01 | Marin | GFNMS, San Francisco Line 6W | 0.5 | RARE | 0 | ABSENT |
| 2025-07-06 | San Mateo | GFNMS, San Mateo Line N8-WN | 10 | COMMON | 2 | PRESENT |
| 2025-07-24 | Marin | GFNMS, Marin Line 4E | 0 | ABSENT | 1 | PRESENT |
| 2025-07-28 | Marin | GFNMS, Marin Line 2E | 0 | ABSENT | 0.5 | RARE |
| 2025-07-02 | Santa Cruz | GFNMS, Santa Cruz Line 25E | 6 | PRESENT | 0.5 | RARE |
| 2025-07-25 | Marin | GFNMS, Marin Line N4-WN | 0 | ABSENT | 0.5 | RARE |
| 2025-07-28 | Marin | GFNMS, Marin Line N2WN | 0 | ABSENT | 0 | ABSENT |
| 2025-07-23 | San Francisco | GFNMS, San Francisco Line N6W | 0.5 | RARE | 0 | ABSENT |
| 2025-07-04 | San Mateo | GFNMS, San Mateo Line 23E | 25 | COMMON | 1 | PRESENT |
| 2025-07-03 | Santa Cruz | GFNMS, Santa Cruz Line 27W | 20 | COMMON | 3 | PRESENT |
| 2025-07-06 | San Mateo | GFNMS, San Mateo Line 8W | 5 | PRESENT | 0.5 | RARE |
| 2025-07-05 | San Mateo | GFNMS, San Mateo Line 10W | 4 | PRESENT | 0.5 | RARE |
| 2025-07-09 | Marin | GFNMS, Marin Line N4-WN | 15 | COMMON | 0.5 | RARE |
| 2025-07-23 | Marin | GFNMS, San Francisco Line 6W | 0 | ABSENT | 0 | ABSENT |
| 2025-07-29 | Marin | GFNMS, Marin Line 11E | 0.5 | RARE | 0 | ABSENT |
| 2025-07-23 | Marin | GFNMS, San Francisco Line 6E | 0.5 | RARE | 0.5 | RARE |
| 2025-07-24 | Marin | GFNMS, Marin Line 4W | 0.5 | RARE | 0 | ABSENT |
| 2025-07-28 | Marin | GFNMS, Marin Line 2W | 0 | ABSENT | 0 | ABSENT |
| 2025-07-29 | Sonoma | GFNMS, Marin Line 11-M | 1 | PRESENT | 0 | ABSENT |
| 2025-08-11 | Orange | San Clemente Pier | 0.5 | RARE | 0 | ABSENT |
| 2025-08-01 | Los Angeles | Palos Verdes Rocky Pt Offshore | 0 | ABSENT | 0 | ABSENT |
| 2025-08-01 | San Francisco | San Francisco, Presidio Pier | 0 | ABSENT | 0.5 | RARE |
| 2025-08-01 | Orange | Dana Pt. Harbor | 0 | ABSENT | 0 | ABSENT |
| 2025-08-04 | Los Angeles | Palos Verdes Rocky Pt Offshore | 0.5 | RARE | 0 | ABSENT |
| 2025-08-01 | Santa Barbara | Santa Barbara Ch., Naples Pt | 59 | ABUNDANT | 0.5 | RARE |
| 2025-08-01 | Orange | Bolsa Chica | 0.5 | RARE | 0 | ABSENT |
| 2025-08-01 | San Luis Obispo | Port San Luis, Diablo Cove | 20 | COMMON | 0.5 | RARE |
| 2025-08-04 | Humboldt | Humboldt Bay, Indian Is. Ch. | 0.5 | RARE | 0 | ABSENT |
| 2025-08-04 | Marin | Tomales Bay, Lease #M430-15 | 0.5 | RARE | 0 | ABSENT |
| 2025-08-04 | San Luis Obispo | Morro Bay, Boat Launch | 5 | PRESENT | 0.5 | RARE |
| 2025-08-01 | Sonoma | Bodega Harbor, USCG Dock | 0 | ABSENT | 0 | ABSENT |
| 2025-08-01 | Marin | Drakes Bay, Chimney Rock LBS | 0 | ABSENT | 0 | ABSENT |
| 2025-08-04 | San Diego | La Jolla, Scripps Pier | 2 | PRESENT | 0.5 | RARE |
| 2025-08-04 | Mendocino | Point Arena Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-08-04 | San Luis Obispo | Cayucos Pier | 4 | PRESENT | 0 | ABSENT |
| 2025-08-07 | Ventura | Ventura, Port Hueneme Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-08-15 | Marin | Drakes Bay, Chimney Rock LBS | 0 | ABSENT | 0 | ABSENT |
| 2025-08-15 | Sonoma | Bodega Harbor, USCG Dock | 0 | ABSENT | 0 | ABSENT |
| 2025-08-14 | Marin | Point Richmond, Ferry Point | 0 | ABSENT | 0 | ABSENT |
| 2025-08-11 | Humboldt | Humboldt Bay, Indian Is. Ch. | 9 | PRESENT | 0 | ABSENT |
| 2025-08-11 | Marin | Tomales Bay, Lease #M430-15 | 0.5 | RARE | 0 | ABSENT |
| 2025-08-18 | Humboldt | Humboldt Bay, Indian Is. Ch. | 7 | PRESENT | 0 | ABSENT |
| 2025-08-18 | Marin | Tomales Bay, Lease #M430-15 | 0 | ABSENT | 3 | PRESENT |
| 2025-08-29 | Sonoma | Bodega Harbor, USCG Dock | 0.5 | RARE | 0 | ABSENT |
| 2025-08-23 | San Mateo | Pillar Point Harbor | 2 | PRESENT | 0 | ABSENT |
| 2025-08-29 | Marin | Point Richmond, Ferry Point | 5 | PRESENT | 1 | PRESENT |
| 2025-08-15 | Orange | Bolsa Chica | 0 | ABSENT | 0 | ABSENT |
| 2025-08-06 | Santa Cruz | Santa Cruz Wharf | 0 | ABSENT | 0 | ABSENT |
| 2025-08-04 | Del Norte | Wilson Creek | 0 | ABSENT | 0 | ABSENT |
| 2025-08-13 | Santa Cruz | Santa Cruz Wharf | 10 | COMMON | 0.5 | RARE |
| 2025-08-05 | Sonoma | Russian River, Jenner | 0 | ABSENT | 0 | ABSENT |
| 2025-08-08 | San Francisco | San Francisco, Presidio Pier | 0.5 | RARE | 0 | ABSENT |
| 2025-08-08 | San Diego | San Diego Bay, U.S. Navy Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-08-08 | Orange | Bolsa Chica | 0.5 | RARE | 0 | ABSENT |
| 2025-08-11 | San Luis Obispo | Morro Bay, Boat Launch | 5 | PRESENT | 3 | PRESENT |
| 2025-08-18 | San Luis Obispo | Morro Bay, Boat Launch | 10 | COMMON | 2 | PRESENT |
| 2025-08-12 | Mendocino | Mendocino, Noyo Harbor | 15 | COMMON | 0.5 | RARE |
| 2025-08-13 | San Diego | Oceanside Harbor | 0 | ABSENT | 0 | ABSENT |
| 2025-08-08 | Los Angeles | Palos Verdes Rocky Pt Offshore | 0 | ABSENT | 0 | ABSENT |
| 2025-08-16 | Mendocino | Point Arena Pier | 10 | COMMON | 0 | ABSENT |
| 2025-08-15 | Los Angeles | Palos Verdes Rocky Pt Offshore | 0 | ABSENT | 0 | ABSENT |
| 2025-08-13 | Los Angeles | Santa Monica Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-08-11 | San Diego | La Jolla, Scripps Pier | 0 | ABSENT | 0.5 | RARE |
| 2025-08-18 | San Diego | La Jolla, Scripps Pier | 1 | PRESENT | 0.5 | RARE |
| 2025-08-25 | Marin | Drakes Bay, Chimney Rock LBS | 0.5 | RARE | 0 | ABSENT |
| 2025-08-25 | Humboldt | Humboldt Bay, Indian Is. Ch. | 5 | PRESENT | 0 | ABSENT |
| 2025-08-25 | San Luis Obispo | Morro Bay, Boat Launch | 0 | ABSENT | 0.5 | RARE |
| 2025-08-25 | Marin | Tomales Bay, Lease #M430-15 | 1 | PRESENT | 0 | ABSENT |
| 2025-08-15 | Los Angeles | Redondo Beach Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-08-22 | Orange | San Clemente Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-08-23 | Orange | Bolsa Chica | 0.5 | RARE | 0 | ABSENT |
| 2025-08-20 | San Diego | Imperial Beach Pier | 0.5 | RARE | 0 | ABSENT |
| 2025-08-21 | Los Angeles | Palos Verdes Rocky Pt Offshore | 0.5 | RARE | 0 | ABSENT |
| 2025-08-15 | San Luis Obispo | Port San Luis, Diablo Cove | 15 | COMMON | 5 | PRESENT |
| 2025-08-26 | San Mateo | Bean Hollow State Beach | 1 | PRESENT | 0 | ABSENT |
| 2025-08-07 | San Luis Obispo | San Simeon Pier | 7 | PRESENT | 0 | ABSENT |
| 2025-08-17 | San Luis Obispo | Cayucos Pier | 6 | PRESENT | 3 | PRESENT |
| 2025-08-22 | Humboldt | Trinidad Pier | 36 | COMMON | 0 | ABSENT |
| 2025-08-24 | San Diego | Pacific Beach Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-08-25 | Sonoma | Shell Beach, Sea Ranch | 25 | COMMON | 0 | ABSENT |
| 2025-08-25 | Los Angeles | Catalina Island, Toyon Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-08-18 | Del Norte | Wilson Creek | 10 | COMMON | 1 | PRESENT |
| 2025-08-19 | Mendocino | Mendocino, Noyo Harbor | 20 | COMMON | 0.5 | RARE |
| 2025-08-20 | Marin | Richardson Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-08-20 | Marin | Richardson Bay | 0 | ABSENT | 0.5 | RARE |
| 2025-08-27 | Santa Cruz | Santa Cruz Wharf | 4 | PRESENT | 0.5 | RARE |
| 2025-08-25 | Sonoma | Kashia Coastal Reserve | 0.5 | RARE | 0 | ABSENT |
| 2025-08-26 | San Mateo | Pillar Point Harbor | 0.5 | RARE | 0 | ABSENT |
| 2025-08-27 | Santa Barbara | Goleta Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-08-13 | Los Angeles | Santa Monica Bay, 3501 | 0 | ABSENT | 0 | ABSENT |
| 2025-08-12 | Orange | Newport Bay, Back Bay | 0.5 | RARE | 0 | ABSENT |
| 2025-08-12 | Del Norte | Wilson Creek | 64 | ABUNDANT | 0.5 | RARE |
| 2025-08-20 | Santa Cruz | Santa Cruz Wharf | 0 | ABSENT | 0 | ABSENT |
| 2025-08-17 | San Luis Obispo | Montana de Oro State Park | 0 | ABSENT | 0.5 | RARE |
| 2025-08-15 | San Luis Obispo | San Luis Obispo, OFFSHORE | 0 | ABSENT | 0 | ABSENT |
| 2025-08-25 | San Diego | La Jolla, Scripps Pier | 3 | PRESENT | 0 | ABSENT |
| 2025-08-13 | Santa Barbara | Goleta Pier | 10 | COMMON | 0 | ABSENT |
| 2025-08-01 | Orange | Newport Bay, Back Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-08-12 | Los Angeles | Santa Monica Bay, 3901 | 0 | ABSENT | 0 | ABSENT |
| 2025-08-20 | Orange | Newport Bay, Back Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-08-15 | San Diego | San Diego Bay, U.S. Navy Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-08-29 | Los Angeles | Catalina Island, Avalon Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-08-16 | San Luis Obispo | San Luis Obispo, OFFSHORE | 52 | ABUNDANT | 0 | ABSENT |
| 2025-08-14 | San Luis Obispo | San Luis Obispo, OFFSHORE | 65 | ABUNDANT | 2 | PRESENT |
| 2025-08-29 | Orange | Bolsa Chica | 0 | ABSENT | 0 | ABSENT |
| 2025-08-28 | San Luis Obispo | Port San Luis, Diablo Cove | 5 | PRESENT | 5 | PRESENT |
| 2025-08-29 | Los Angeles | Palos Verdes Rocky Pt Offshore | 0 | ABSENT | 0 | ABSENT |
| 2025-08-29 | Los Angeles | Catalina Island, Avalon Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-08-27 | San Diego | San Diego Bay, U.S. Navy Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-08-29 | San Diego | Oceanside Harbor | 0 | ABSENT | 0 | ABSENT |
| 2025-08-25 | Del Norte | Wilson Creek | 0.5 | RARE | 0 | ABSENT |
| 2025-08-27 | Santa Barbara | Santa Barbara, Mohawk Reef | 0.5 | RARE | 0 | ABSENT |
| 2025-08-26 | Los Angeles | Santa Monica Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-08-23 | San Luis Obispo | Cayucos Pier | 0.5 | RARE | 0 | ABSENT |
| 2025-08-27 | Santa Barbara | Santa Barbara Ch., Naples Pt | 0.5 | RARE | 0 | ABSENT |
| 2025-08-14 | Los Angeles | Santa Monica Bay, 3201 | 0 | ABSENT | 0 | ABSENT |
| 2025-08-27 | Mendocino | Mendocino, Noyo OFFSHORE | 25 | COMMON | 0 | ABSENT |
| 2025-08-27 | San Diego | Imperial Beach Pier | 5 | PRESENT | 0 | ABSENT |
| 2025-08-27 | Mendocino | Mendocino, Noyo Harbor | 3 | PRESENT | 0.5 | RARE |
| 2025-08-15 | Mendocino | Point Arena Pier | 3 | PRESENT | 0 | ABSENT |
| 2025-08-27 | Orange | Newport Bay, Back Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-08-07 | Orange | Newport Bay, Back Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-09-05 | San Luis Obispo | San Simeon Pier | 9 | PRESENT | 2 | PRESENT |
| 2025-09-01 | Marin | Tomales Bay, Lease #M430-15 | 0.5 | RARE | 0 | ABSENT |
| 2025-09-02 | Humboldt | Humboldt Bay, Indian Is. Ch. | 35 | COMMON | 0 | ABSENT |
| 2025-09-02 | San Luis Obispo | Morro Bay, Boat Launch | 15 | COMMON | 0 | ABSENT |
| 2025-09-08 | San Luis Obispo | Morro Bay, Boat Launch | 0.5 | RARE | 0 | ABSENT |
| 2025-09-08 | Marin | Tomales Bay, Lease #M430-15 | 0.5 | RARE | 0 | ABSENT |
| 2025-09-08 | Humboldt | Humboldt Bay, Indian Is. Ch. | 3.5 | PRESENT | 0 | ABSENT |
| 2025-09-02 | Marin | Richmond, Marina Bay Harbor | 8 | PRESENT | 0 | ABSENT |
| 2025-09-15 | Marin | Drakes Bay, Chimney Rock LBS | 0 | ABSENT | 0 | ABSENT |
| 2025-09-15 | Humboldt | Humboldt Bay, Indian Is. Ch. | 0.5 | RARE | 0 | ABSENT |
| 2025-09-15 | San Luis Obispo | Morro Bay, Boat Launch | 0 | ABSENT | 2 | PRESENT |
| 2025-09-09 | Del Norte | Hunter Rock, north | 5 | PRESENT | 0 | ABSENT |
| 2025-09-10 | Del Norte | Wilson Creek | 6 | PRESENT | 0 | ABSENT |
| 2025-09-03 | San Diego | San Diego Bay, U.S. Navy Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-09-01 | Mendocino | Point Arena Pier | 15 | COMMON | 0 | ABSENT |
| 2025-09-10 | Santa Cruz | Santa Cruz Wharf | 0.5 | RARE | 0 | ABSENT |
| 2025-09-02 | San Diego | La Jolla, Scripps Pier | 2 | PRESENT | 0 | ABSENT |
| 2025-09-15 | Marin | Tomales Bay, Lease #M430-15 | 0 | ABSENT | 0 | ABSENT |
| 2025-09-06 | Los Angeles | Palos Verdes Rocky Pt Offshore | 0 | ABSENT | 0 | ABSENT |
| 2025-09-05 | San Mateo | Pacifica Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-09-08 | Ventura | Ventura, Port Hueneme Pier | 3 | PRESENT | 0 | ABSENT |
| 2025-09-05 | Los Angeles | Point Dume, offshore | 0 | ABSENT | 0 | ABSENT |
| 2025-09-03 | Santa Cruz | Santa Cruz Wharf | 0 | ABSENT | 0 | ABSENT |
| 2025-09-11 | San Francisco | San Francisco, Presidio Pier | 1 | PRESENT | 1 | PRESENT |
| 2025-09-09 | Los Angeles | Santa Monica Pier | 8 | PRESENT | 0 | ABSENT |
| 2025-09-04 | Del Norte | Wilson Creek | 1 | PRESENT | 0 | ABSENT |
| 2025-09-03 | Orange | Newport Bay, Back Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-09-04 | San Diego | Imperial Beach Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-09-05 | Orange | Bolsa Chica | 0.5 | RARE | 0 | ABSENT |
| 2025-09-11 | Orange | Dana Pt. Harbor | 0 | ABSENT | 0 | ABSENT |
| 2025-09-12 | Orange | Bolsa Chica | 0 | ABSENT | 0 | ABSENT |
| 2025-09-14 | San Mateo | Pillar Point Harbor | 0.5 | RARE | 0 | ABSENT |
| 2025-09-06 | Santa Barbara | Santa Barbara Island | 0 | ABSENT | 0 | ABSENT |
| 2025-09-09 | Orange | Newport Bay, Back Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-09-10 | San Mateo | Bean Hollow State Beach | 0 | ABSENT | 0 | ABSENT |
| 2025-09-10 | San Mateo | Pillar Point | 0 | ABSENT | 0 | ABSENT |
| 2025-09-22 | Humboldt | Humboldt Bay, Indian Is. Ch. | 1 | PRESENT | 0 | ABSENT |
| 2025-09-26 | San Luis Obispo | Cayucos Pier | 0 | ABSENT | 0.5 | RARE |
| 2025-09-07 | Los Angeles | Catalina Island, Pedestal Rock | 0 | ABSENT | 0 | ABSENT |
| 2025-09-22 | Marin | Tomales Bay, Lease #M430-15 | 0.5 | RARE | 0.5 | RARE |
| 2025-09-22 | San Luis Obispo | Morro Bay, Boat Launch | 1 | PRESENT | 0.5 | RARE |
| 2025-09-10 | Santa Barbara | Goleta Pier | 5 | PRESENT | 0 | ABSENT |
| 2025-09-17 | Santa Cruz | Santa Cruz Wharf | 0 | ABSENT | 0 | ABSENT |
| 2025-09-23 | San Luis Obispo | Pismo Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-09-23 | San Luis Obispo | San Luis Obispo, Cal Poly Pier | 10 | COMMON | 0 | ABSENT |
| 2025-09-08 | San Diego | La Jolla, Scripps Pier | 4 | PRESENT | 0.5 | RARE |
| 2025-09-03 | Santa Cruz | CDFG Trawl Block 501, Waddell | 11 | COMMON | 0 | ABSENT |
| 2025-09-22 | San Diego | La Jolla, Scripps Pier | 3 | PRESENT | 0 | ABSENT |
| 2025-09-26 | Orange | Bolsa Chica | 0 | ABSENT | 0 | ABSENT |
| 2025-09-16 | Orange | Bolsa Chica | 0 | ABSENT | 0 | ABSENT |
| 2025-09-23 | Mendocino | Mendocino, Noyo Harbor | 0.5 | RARE | 0 | ABSENT |
| 2025-09-19 | San Diego | San Diego Bay, U.S. Navy Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-09-22 | Del Norte | Wilson Creek | 0 | ABSENT | 0 | ABSENT |
| 2025-09-23 | Los Angeles | Palos Verdes, OFFSHORE | 3 | PRESENT | 0 | ABSENT |
| 2025-09-24 | San Diego | Imperial Beach Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-09-24 | Orange | Newport Bay, Back Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-09-15 | San Diego | La Jolla, Scripps Pier | 1 | PRESENT | 0 | ABSENT |
| 2025-09-24 | Santa Barbara | Goleta Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-09-29 | San Luis Obispo | Morro Bay, Boat Launch | 0.5 | RARE | 0.5 | RARE |
| 2025-09-24 | Santa Cruz | Santa Cruz Wharf | 0 | ABSENT | 0 | ABSENT |
| 2025-09-28 | Marin | Fort Baker | 0 | ABSENT | 0.5 | RARE |
| 2025-09-29 | Sonoma | Bodega Harbor, USCG Dock | 0 | ABSENT | 1 | PRESENT |
| 2025-09-11 | Del Norte | Wilson Creek | 0 | ABSENT | 0 | ABSENT |
| 2025-09-09 | Los Angeles | Manhattan Beach Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-09-11 | Orange | San Clemente Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-09-10 | Los Angeles | Catalina Island, Toyon Bay | 0 | ABSENT | 0 | ABSENT |
| 2025-09-14 | Ventura | Ventura Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-09-18 | Del Norte | Wilson Creek | 0 | ABSENT | 0 | ABSENT |
| 2025-09-23 | San Mateo | Pillar Point Harbor | 0 | ABSENT | 0 | ABSENT |
| 2025-09-13 | Los Angeles | Palos Verdes Rocky Pt Offshore | 0.5 | RARE | 0 | ABSENT |
| 2025-09-23 | Marin | GFNMS, Marin Line 4E | 0 | ABSENT | 1 | PRESENT |
| 2025-09-29 | Humboldt | Humboldt Bay, Indian Is. Ch. | 0 | ABSENT | 0.5 | RARE |
| 2025-09-29 | Marin | Tomales Bay, Lease #M430-15 | 0 | ABSENT | 1 | PRESENT |
| 2025-09-07 | San Luis Obispo | San Simeon Pier | 2 | PRESENT | 0 | ABSENT |
| 2025-09-27 | Los Angeles | Palos Verdes Rocky Pt Offshore | 0.5 | RARE | 0 | ABSENT |
| 2025-09-19 | Orange | Bolsa Chica | 0.5 | RARE | 0 | ABSENT |
| 2025-09-29 | Orange | San Clemente Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-09-21 | San Mateo | Pacifica Pier | 0.5 | RARE | 0 | ABSENT |
| 2025-09-08 | San Luis Obispo | Port San Luis, Diablo Cove | 8 | PRESENT | 0.5 | RARE |
| 2025-09-10 | San Diego | San Diego Bay, U.S. Navy Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-09-24 | Marin | GFNMS, San Francisco Line 6E | 0.5 | RARE | 1 | PRESENT |
| 2025-09-23 | Marin | GFNMS, Marin Line 4W | 4 | PRESENT | 0 | ABSENT |
| 2025-09-22 | San Francisco | GFNMS, San Francisco Line N6WN | 0.5 | RARE | 0 | ABSENT |
| 2025-09-03 | Mendocino | Mendocino, Noyo Harbor | 25 | COMMON | 0 | ABSENT |
| 2025-09-08 | Los Angeles | Palos Verdes, OFFSHORE | 0 | ABSENT | 0 | ABSENT |
| 2025-09-28 | San Luis Obispo | San Simeon Pier | 4 | PRESENT | 0 | ABSENT |
| 2025-09-28 | Humboldt | Trinidad Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-09-28 | San Luis Obispo | Cayucos Pier | 0 | ABSENT | 0 | ABSENT |
| 2025-09-06 | Sonoma | Kashia Coastal Reserve | 0 | ABSENT | 0 | ABSENT |
| 2025-09-17 | Marin | GFNMS, Marin Line 2E | 0 | ABSENT | 3 | PRESENT |
| 2025-09-19 | Marin | GFNMS, Marin Line N11-WN | 0 | ABSENT | 0 | ABSENT |
| 2025-09-21 | Marin | GFNMS, Marin Line N4-WN | 0 | ABSENT | 1 | PRESENT |
| 2025-09-29 | San Diego | La Jolla, Scripps Pier | 0 | ABSENT | 0.5 | RARE |
| 2025-09-24 | Marin | GFNMS, San Francisco Line 6W | 0 | ABSENT | 0.5 | RARE |
Domoic acid-related strandings, July - September 2025
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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), 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
This public acknowledgment serves to honor and respect Indigenous peoples and their land on which our organization resides. UC San Diego was built upon the territory of the Kumeyaay Nation. From time immemorial, the Kumeyaay people have been a part of this land, coast, and sea. Today, the Kumeyaay people continue to maintain their political sovereignty and cultural traditions as vital members of the San Diego community.The nature and extent of observation that the Southern California Coastal Ocean Observing System directly supports is entirely within the historic purview of many distinct Indigenous nations & cultures, who subsisted on and shaped these coasts. With deep admiration & acknowledgement to these Indigenous peoples past and present, we hope to contribute our services to the shared vision of coastal stewardship and connection which they have created.
Photo credit: Rich Walsh, SIO.
California HAB Bulletin
All data and reports have been synthesized by SCCOOS for the California Harmful Algal Bloom Monthly Bulletin.
Data Access & Resources:
C-HARM, NOAA CoastWatch ERDDAP
Toxic Phytoplankton Observations, CDPH
Imaging FlowCytoBot Dashboard
CalHABMAP Datasets, SCCOOS ERDDAP