Harmful Algal Blooms in the California Current

Microscopic planktonic algae are the basis of the ocean’s food chains supporting fisheries and aquaculture, however algal blooms can also have negative effects (aka red tides), causing widespread mortality of marine life. Of the more than 5000 phytoplankton species less than 10% bloom to densities of more than 1 million per liter and only 1% have the ability to produce harmful toxins killing marine organisms and in some cases humans. Worldwide there has been an increase in frequency, intensity and geographic extent of harmful algal blooms (HABs) as seen in the number of cases of paralytic shellfish poisonings in 1970 compared with 1990 (Hallegraeff 1993). There are a number of potential hypotheses that have been proposed to explain the increase in HABs including, increased scientific awareness of toxic species, increased utilization of coastal waters and fisheries, increased transport of dinoflagellate resting cysts, stimulation of plankton blooms by eutrophication and/or changing oceanographic conditions. Studies of HABs and toxic dinoflagellates have a number of challenges including the scarcity of phytoplankton surveys, poor taxonomic information, difficulties culturing toxic species and changes in the toxin production of phyotoplankton. In this symposium we invite scientists working on HABs in the California Current to present results from their work as well as make recommendations for ways to move HAB research forward. We anticipate that this symposium will bring the long-term oceanographic sampling tradition of CalCOFI and the HAB research communities together to enhance collaboration, survey planning, data sharing, prediction capabilities and funding opportunities. 

For more information contact Laura Rogers Bennett

The 2012 CalCOFI Conference will be held at the Asilomar Conference Center in Pacific Grove, California, December 3-5. 

The California Department of Public Health (CDPH) is advising consumers not to eat recreationally harvested mussels and clams, commercially or recreationally caught anchovy and sardines, or the internal organs of commercially or recreationally caught crab and lobster taken from the northern Channel Islands located offshore of Ventura and Santa Barbara counties. Dangerous levels of the nerve toxin domoic acid have been detected in some of these species and may be present in the other species not yet tested. Domoic acid is a naturally occurring toxin that can cause illness or death in humans.

The harmless, green foam has returned yet another year to San Diego County beaches. Researchers at Scripps Institution of Oceanography have determined that the bright green color is caused by a bloom of phytoplankton, Tetraselmis spp. This green flagellate is roughly 10 micrometers in size, and has been found in concentrations as dense as 15 million cells per liter of seawater. The foam has become more prevalent this week, though it has been observed off and on since the first week of July. It's patchy distribution makes it visible only at some beaches and the foam becomes more apparent in the afternoon when the wind and waves mix the surface waters. Tetraselmis has bloomed each summer since 2009 with blooms lasting from one week to several months. There are no documented health hazards with swimming or fishing in areas of Tetraselmis blooms.

To learn more about algal bloom monitoring in San Diego County and the California region, visit the SCCOOS Harmful  Algal Bloom Monitoring Program website.

26 September 2011

This week red to brownish-red discolored waters became more evident as the bloom of Lingulodinium polyedrum continues along the coast of San Diego County.  Areas where the red waters are observed during the day can bioluminesce at night, producing a striking blue color when agitated from breaking waves, swimming fishes and even the movement of your hands and feet.

Sampling efforts by SCCOOS HAB researchers at Scripps Institution of Oceanography have found cell abundances of this dinoflagellate to be over 1 million cells/liter and chlorophyll values at 43.92 mg/m³ at Scripps Pier in La Jolla (average values range from 0-1,000 cells/L of L. polyedrum and 2.49 mg/m³ for chlorophyll). This bloom began near the end of August and could last for several weeks to a couple of months. 

To read more about Lingulodinium polyedrum and our monitoring efforts visit these websites:

http://www.sccoos.org/data/habs/species.php?specie=Lingulodinium polyedrum

http://www.sccoos.org/data/chlorophyll/abouthabs.php

Here are some answers to other commonly asked questions:

Will the water make me sick?

The water is not harmful to swim in though increased ear and sinus infections have been reported during blooms.  This is most likely due to increased bacteria that are associated with increased amounts of organic material produced and degraded during bloom conditions. Swimmers may reduce their risk for infections by rinsing their ears and any wounds after exposure, drying their ear canals with an equal mixture of isopropyl alcohol and 2% acetic acid, and seeking prompt medical attention if any signs of infection develop.

Lingulodinium polyedrum is a known producer of yessotoxin, an algal toxin that can accumulate in filter feeding organisms such as mussels and some fishes, but no human deaths or poisoning have been reported due to yessotoxin.  Keep in mind, you can not drink enough seawater to make yourself sick from this toxin or other algal toxins currently found in California coastal waters.

Why do dinoflagellates bioluminesce?

One theory is that the bioluminescence both deters grazers of the dinoflagellates, and also attracts the predators of the grazers which are mostly visually oriented organisms such as fish (the so-called "burglar hypothesis").  Bioluminescence is a light produced through an enzymatic chemical reaction within the cells of Lingulodinium polyedrum.

On Tuesday, March 8, 2011, King Harbor in the City of Redondo Beach experienced a massive fish kill (estimates are in the millions of fish killed), apparently mostly Pacific sardine. This event has received national and global attention. My research group at the University of Southern California has been actively working and monitoring King Harbor as a site of recurrent algal blooms since a massive fish kill occurred there in 2005. The exact cause of the 2005 event was never clearly determined, but it coincided with a large microalgal bloom. Thus, the buildup of algae and perhaps toxins produced by harmful algal species, were implicated as playing a role in the fish mortality.

In response to the 2005 mortality event, we established a monitoring program there in 2006 to characterize the algal species at the site, and subsequently a suite of instruments to measure water quality in 2007, and we have maintained those instruments and characterized the microalgae in the water through the present time. These instruments, and additional measurements made at the time of the event on March 8th and immediately following the mortality event, are summarized below:

Our sensor packages in the water recorded pertinent environmental parameters (temperature, salinity, dissolved oxygen, and chlorophyll fluorescence which is a proxy for microalgal biomass) prior to and during the event. These instruments indicated a precipitous drop in dissolved oxygen coincident with the mortality event. Based on the information collected by the sensor packages, we conclude that depletion of dissolved oxygen was unquestionably the immediate cause of the mortality event.

Profiles of dissolved oxygen made in and around King Harbor on March 8 indicated exceptionally low dissolved oxygen concentrations within the harbor, with increasing concentrations of oxygen in the outer harbor region. Severely depleted levels of dissolved oxygen persist today (March 10) in parts of the harbor in the wake of the mortality event.

It is not clear at this time whether the oxygen depletion in King Harbor on the 8th occurred solely due to respiration by the very large population of sardines that entered the harbor days prior to the mortality event. It is possible that an influx of coastal water with a low concentration of oxygen may have occurred, contributing to the low oxygen conditions. We are continuing to examine this possibility.

Our continuously-recording instruments measured relatively low chlorophyll concentrations leading up to, during, and immediately following the event (<2 ug/l). Therefore, we have ruled out the possibility of a massive buildup of algal biomass as a factor contributing to the mortality event (high algal biomass was a presumed contributor to the 2005 mortality event).

In addition, analysis of water samples collected on the day of the event in King Harbor indicated very low microalgal biomass in general, and the virtual absence of potentially harmful or toxic algal species in the water.

Despite the lack of toxic algal species in the water at King Harbor during this event, analyses of the gut contents of fish collected on March 8th have tested strongly positive for domoic acid. Domoic acid is a powerful neurotoxin produced by a specific type of microalgae. The algae are strained from the water by plankton-eating fish such as sardines and anchovy, and the toxin is often found concentrated in the stomach contents of these fish during a toxic algal bloom. Domoic acid can cause a variety of neurological disorders, and death, of animals consuming fish contaminated with the neurotoxin. Research also indicates that domoic acid poisoning can cause abnormal swimming behavior in some fish. It is possible that high levels of domoic acid in the sardines in King Harbor may have exacerbated physiological stress of the fish brought on by oxygen depletion of the water, or may have been a contributing explanation for them congregating in the harbor at very high abundances, but this has not been confirmed.

We believe that the fish ingested the toxin offshore (before entering the harbor) because domoic acid was not detected in the water within King Harbor on the day of the event. Additionally, during our 5-year study we have not observed significant concentrations of domoic acid in King Harbor. We have confirmed that plankton collected from the coastal ocean approximately 20 km southwest of Redondo Beach on March 9 had very high concentrations of domoic acid in the plankton. That finding support the idea that the fish ingested the toxin in coastal waters before entering the harbor.

This is the present status of our knowledge on this event. My lab is continuing to analyze for other algal toxins in the fish collected at the time of the mortality event. We are also continuing to monitor the chemical conditions (especially dissolved oxygen) and biological conditions (algal abundance) within the harbor in order to characterize the recovery of the harbor, and/or any response of the microalgal community to the release of nutrients by the decomposing fish.

We are continuing to characterize the toxic bloom now taking place in the adjacent coastal ocean, and we are acquiring oceanographic information that will help determine if a pulse of low-oxygen water from the coastal ocean may have entered King Harbor and contributed to the fish mortality event.

An Akashiwo sanguinea bloom continues in the San Diego region since November 29, 2010 with patchy distribution along San Diego county beaches. Extra samples collected by Scripps Institution of Oceanography at Imperial beach and Ocean Beach Piers indicate a bloom of Akashiwo sanguinea at these locations and at Scripps Pier.  As of Monday, December 13th, brownish-red discolored water was noted at Imperial Beach with chlorophyll levels up to 135 mg/m³. Discolored water has been noted at various San Diego beaches and bays over the last two weeks.

These single-celled organisms are one of several species that are responsible for harmful algal blooms (HABs), and are actively monitored along the California coast.  While this organism is not currently known to produce toxins, it does generate a surfactant-like protein that can be deleterious to marine life, including marine birds. This protein may coat the feathers of seabirds and reduce their natural water-proofing ability, causing them to suffer hypothermia.  Although the mechanism is not clearly understood, Akashiwo sanguinea blooms are also thought to be responsible for massive fish kills.

To learn more about Akashiwo sanguinea click here

Press release issued by the California Department of Public Health- October 18, 2010

The California Department of Public Health (CDPH) is warning consumers not to eat sport-harvested shellfish or some parts of crustaceans or small finfish from offshore the Channel Islands. Elevated levels of the toxin, domoic acid, has been detected in recent samples of mussels, clams, scallops, and the viscera of lobster and crab. Domoic acid can be harmful to people.

This warning does not apply to commercially sold clams, mussels, scallops or oysters. State law only permits state-certified commercial shellfish harvester or dealer to sell these products. Shellfish sold by certified harvesters and dealers are subject to frequent mandatory testing.

No cases of human poisoning from domoic acid are known to have occurred in California.

Symptoms of domoic acid poisoning can occur within 30 minutes to 24 hours after eating toxic seafood. In mild cases, symptoms may include vomiting, diarrhea, abdominal cramps, headache and dizziness. These symptoms disappear within several days. In severe cases, the victim may experience difficulty breathing, confusion, disorientation, cardiovascular instability, seizures, excessive bronchial secretions, permanent loss of short-term memory, coma and death.

To receive updated information about shellfish poisoning and quarantines, call CDPH toll-free “Shellfish Information Line” at (800) 553-4133.

Through the sampling efforts of the SCCOOS HAB Monitoring sites and additional efforts by the Orange County Sanitation District, domoic acid has been detected in Santa Barbara (Stearn’s Wharf, Gaviota Pier and Goleta Pier), Los Angeles (Redondo Beach Pier) and Orange (Newport Pier and offshore samples) Counties. Additionally, a California Sea Lion that stranded July 30th with domoic acid toxicity symptoms tested positive for DA in a serum sample.

Due to the large influx of stranded marine mammals and the detection of domoic acid in seawater samples, it appears that a domoic acid event is occurring in southern California.

The harmless, green foam that invaded Orange and LA County beaches in late July has extended down to San Diego County. Last week, researchers at Scripps Institution of Oceanography also found Tetraselmis, a microscopic green algae, in samples from Scripps Pier.  The foam has persisted this week, though it's patchy distribution make it visible only at some beaches and the foam becomes more apparent in the afternoon when the wind and waves mix the surface waters.  This green flagellate which is only 10 micrometers in size has been found in concentrations as dense as 15 million cells per liter of seawater.  There are no documented health hazards with swimming or fishing in areas of Tetraselmis blooms.

Green slime appeared at the surface of the coastal waters from Long Beach down through Newport Beach last week. Samples were collected by the County of Orange Health Care Agency, the Orange County Sanitation District and the Southern California Coastal Water Research Project. Researchers at University of Southern California identified the samples as being highly dominated by one species, Tetraselmis, which is very small flagellated chlorophyte. This is not a harmful species so there are no documented health hazards from this organism. The University of Southern California researchers have seen this species in past summers in southern California, but it appears to be more widespread this year.

To learn more about algal bloom monitoring in the LA and Orange County areas, click here.

King Harbor Marina in Redondo Beach, California, experienced a red tide caused by the dinoflagellate Akashiwo sanguinea over a two week period in late May and early June.  During the height of the bloom, extremely dense patches of Akashiwo sanguinea (chlorophyll values of 3518.4 mg/m³) were observed along the seawall located at the back of the marina. However the chlorophyll concentrations at the Harbor Patrol dock, located approximately 0.25 miles away near the mouth of the marina, were considerably less (52.42 mg/m³).  These single-celled organisms are one of several species that are responsible for harmful algal blooms (HABs), and are actively monitored along the California coast.  While this organism is not currently known to produce toxins, it does generate a surfactant-like protein that can be extremely deleterious to marine life, especially marine birds. As the protein coats the animal’s feathers, it greatly reduces their natural water-proofing ability, causing them to suffer hypothermia.  Although the mechanism is not clearly understood, Akashiwo sanguinea blooms are also thought to be responsible for massive fish kills.

To learn more about Akashiwo sanguinea click here

To learn more about monitoring in King Harbor Marina click here

Patches of discolored reddish-brown waters have been seen along San Diego County beaches from Oceanside to Imperial Beach over the past few weeks.  Our monitoring efforts show that these dense blooms are caused primarily by a type of phytoplankton, a dinoflagellate called Lingulodinium polyedrum. Cell counts show a population increase from an average of 7,000 cells/liter to 200,000 cells/liter in the patches, and a 10-fold increase in the chlorophyll content from the average value of 2 mg/m³. Areas where the red waters are observed during the day can have a drastically different look at night when these cells bioluminesce producing a striking blue color when agitated from breaking waves, swimming fishes and even the movement of your hands and feet.  The water is not harmful to swim in though we are currently testing for toxins that could accumulate in filter feeding organisms such as mussels and some fishes.  This species has been associated with previous red tides in southern California, and blooms of this current magnitude (chlorophyll greater than 20 mg/m³) have occurred in five years out of the last twenty five years.

Low abundance of potentially toxic species of algae were found at the coast in Santa Barbara, Los Angeles, and San Diego counties.  No impacts are expected at the coast.  Reports of discolored water have been received at Scripps Pier in San Diego county.

CALIFORNIA DEPARTMENT OF PUBLIC HEALTH
FOR IMMEDIATE RELEASE
October 28, 2009

CONTACT:
Al Lundeen
Ron Owens
(916) 440-7259
PH09-99

CDPH LIFTS SPORT-HARVESTED MUSSELS QUARANTINE

SACRAMENTO – The California Department of Public Health (CDPH) announced today that the statewide annual quarantine on mussels taken by sport harvesters from California’s ocean waters ends at midnight on Saturday, October 31 for all counties except Del Norte, Humboldt, and San Luis Obispo. Aside for these three counties, samplings of mussels show no detectable levels of dangerous toxins and human consumption of shellfish is now considered safe.

The annual quarantine is issued for the entire California coastline, usually from May 1 through October 31. The quarantine applies only to sport-harvested mussels. Commercially harvested shellfish are not included in the quarantine as other steps are taken to assure oysters, clams and mussels entering the marketplace are free of toxins.

Paralytic shellfish poisoning (PSP) is a form of nervous system poisoning. Concentrated levels of the PSP toxins can develop in mussels and other bivalve shellfish when they feed on certain naturally occurring marine plankton.

A second form of poisoning, Domoic Acid Poisoning (DAP) -- sometimes referred to as Amnesic Shellfish Poisoning (ASP) -- has been linked to natural food sources for filter-feeding animals like bivalve shellfish. No known cases of human ASP have occurred in California this season. Domoic acid has been linked to several poisonings of marine mammals along the Pacific Coast and may have caused several mild cases of human poisoning in the state of Washington.

CDPH’s shellfish sampling and testing programs for PSP and ASP issue warnings or quarantines when needed. Local health departments, various state and federal agencies and others participate in the monitoring program.

Consumers can receive updated information about shellfish poisoning by calling the "Shellfish Information Line" at (800) 553-4133.

www.cdph.ca.gov

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A number of bird and marine mammal strandings have occurred in the past week in the Los Angeles and Orange County areas with a possible link to domoic-acid (DA) poisoning. Significant numbers of the domoic-acid producing diatom Pseudo-nitzschia have been detected at SCCOOS Harmful Algal Bloom study sites at Stearn's Wharf, Newport Pier, and Scripps Pier over the past week. USC Webb Gliders running transects around Catalina Island also show a significant subsurface chlorophyll maximum. Additionally, low levels of domoic acid were detected in and around the Los Angeles Harbor at the end of April.

Scientists from USC will be coordinating with the Los Angeles and Orange County Sanitation Districts to collect seawater samples this week to verify the extent of this event. Further updates will follow as analysis is completed on seawater and marine mammal samples.

The reddish water or "red tide" off Imperial Beach's coast is safe for water enthusiasts, but signals that local mussels may be toxic, county health officials said Tuesday.