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 domoic acid (DA). In October, suitable habitat for Pseudo-nitzschia spp. was spread throughout coastal California, as it has been for many months, but with only coastal ribbons of high probability in the Bight south of the Santa Barbara Channel. Habitat suitability increased in intensity in regions north of the Santa Barbara Channel. C-HARM predicted high but patchy probabilities of high particulate DA (pDA) throughout most of the state, with the greatest probabilities of pDA along sections of the Humboldt/North County coastline, Sonoma coastline, Half Moon Bay, the southern portion of Monterey Bay, and the Southern California Bight (including the Santa Barbara Channel and the transition region around Pt Conception). Those probabilities are notably low along the San Luis Obispo coastline, as they were in August and September, which seems inconsistent with the higher Pseudo-nitzschia spp. abundances measured by CDPH in that zone in October (discussed more below). Persistent high probabilities in the Bight south of the Santa Barbara Channel seem to be due to a two-year long salinity anomaly that is driving the pDA model to over-predict the probability of domoic acid, however, this is still under investigation. Salinity is not an important component of the cellular DA (cDA) model, and we do not see this pattern in the cDA model output. C-HARM indicates very high probabilities in cDA distributed in patches. These patches wax and wane over the course of the month but are persistently high along the Humboldt Coastlilne, Sonoma coastline and Marin County, the southern portion of Monterey Bay, just south of Monterey Bay, and around the Santa Barbara Channel Islands later in the month (as was the case in September).

In comparison with the Harmful Algal Bloom Monitoring and Alert Program (HABMAP) measurements where we have the October data currently available, bloom levels of the P. "delicatissima" and "seriata" size class occurred at various times throughout the month in the Southern California Bight at Scripps Pier (San Diego Co.), Newport Beach Pier (Orange Co.), and Stearns Wharf (Santa Barbara Co.), but not at the Santa Monica Pier (Los Angeles Co.). October domoic acid data were only currently available for the Santa Cruz Wharf and Newport Beach Pier where no domoic acid was detected. In the case of Newport Beach Pier, only the Pseudo-nitzschia delicatissima size class was blooming towards the end of October, and no Pseudo-nitzschia activity at the Santa Cruz Wharf. High C-HARM pDA probabilities in the southern Monterey Bay but not northern Monterey Bay are consistent with HABMAP time series showing little activity related to both Pseudo-nitzschia presence and DA at the Santa Cruz Wharf but showing bloom levels of both the "seriata" and "delicatissima" size classes at Monterey Wharf (south bay). High abundances of the more toxigenic Pseudo-nitzschia seriata size class at Scripps Pier and Newport Beach Pier are consistent with a high intensity ribbon of high probabilities along the coastline in the Bight as well as high pDA probabilities there. However, note the caveat regarding C-HARM pDA probabilities in the Bight mentioned above.

CDPH recorded their highest relative abundances of Pseudo-nitzschia seriata size class in Humboldt Bay area, northern Monterey Bay (in contrast to HABMAP results and the pDA model predictions from C-HARM), the Santa Barbara Channel (especially the north side of Santa Cruz Island), the Los Angeles and Orange County areas, as well as San Luis Obispo County. HABMAP also recorded a slight rise in the seriata size class of Pseudo-nitzschia with no associated pDA at the end of September, which corrobrates the CDPH observations. These results are generally consistent with the HABMAP patterns, with the exception of the Santa Cruz area. Most closures or advisories from CDPH related to the threat of Amnesic Shellfish Poisoning (ASP) from domoic acid took place in the Humboldt and Sonoma Counties on or after October 15th. The Dungeness crab fishery has been delayed due to both poor meat quality and the threat of ASP in some areas, notably Sonoma/Mendocino Counties. Marine mammal strandings from DA toxicosis were down in October from September and were only recorded along the central coast, although three from LA to San Diego are consistent with C-HARM predictions of high pDA probability in much of the Bight (even if possibly over-predicted) and moderate probabilites of cDA risk in the area. This does not mean there have not been North Coast strandings from DA toxicosis, only that we are not acquiring data from the North Coast Marina Mammal Center yet.

Alexandrium - There was no activity related to Alexandrium spp. or paralytic shellfish (PSP) toxins seen in HABMAP or CDPH records for October.

Santa Cruz Wharf

Water samples were collected at Santa Cruz Wharf five times in the month of October. Pseudo-nitzschia seriata group was detected below bloom levels on October 9th and Alexandrium were detected below bloom levels on October 2nd. Domoic acid was not detected on October 2nd and the results for the water samples later in the month are not yet available. Santa Cruz Wharf does not count for Pseudo-nitzschia delicatissima group. 

Monterey Wharf

Water samples were collected at Monterey Wharf five times in the month of October. Pseudo-nitzschia delicatissima was detected above bloom levels on October 9th and October 16th and Pseudo-nitzschia seriata was detected below bloom levels in all five samples. Alexandrium spp. were detected below bloom levels on October 20th. Domoic Acid results are not yet available for the month of October. 

Cal Poly Pier

Cal Poly Pier phytoplankton counts and domoic acid results are not yet available for the month of October. 

Stearns Wharf

Water samples were collected at Stearns Wharf four times in the month of October. Pseudo-nitzschia delicatissima group was detected above bloom levels on October 7th. Pseudo-nitzschia seriata group was detected below bloom levels in all four samples and Alexandrium spp. were not detected in any of the samples. Domoic Acid results are not yet available for Stearns Wharf.

Santa Monica Pier

Water samples were collected at Santa Monica Pier four times in the month of October. Pseudo-nitzschia delicatissima, Pseudo-nitzschia seriata and Alexandrium spp. were not detected above bloom levels in any of the October water samples and domoic acid results are not yet available for the month of October. 

Scripps Pier

Water samples were collected two times at Scripps Pier in the month of October. Pseudo-nitzschia delicatissima was detected above bloom levels on October 7th and 14th. Pseudo-nitzschia seriata were detected below bloom levels and Alexandrium spp. were not detected in any of the water samples. Particulate domoic acid results are not yet available for Scripps Pier for June - October. 

At this time we do not have data from the North Coast Marine Mammal Center or the Channel Islands Marine Wildlife Institute.  

California Sea Bird Strandings from Suspected DA Toxicosis

Data coming soon from Wildlife Rehabilitation Medical Database (WRMD) and BeachCOMBERS.