What's killing hundreds of sea lions and dozens of dolphins along the Southern California coast?
Summer Lin
Tue, June 20, 2023
Sea lions recuperate at the Marine Mammal Care Center in San Pedro on Tuesday. More than 1,000 marine mammals have become ill or died this month because of toxic algae blooms along the coast of Southern California, according to the National Oceanic and Atmospheric Administration.
Dr. Alissa Deming, left, and veterinarian assistant Malena Berndt give anti-seizure medicine to a California sea lion named Patsy in a recovery room at the Pacific Marine Mammal Center in Laguna Beach after it was found having seizures from toxic algae blooms.
Summer Lin
Tue, June 20, 2023
Sea lions recuperate at the Marine Mammal Care Center in San Pedro on Tuesday. More than 1,000 marine mammals have become ill or died this month because of toxic algae blooms along the coast of Southern California, according to the National Oceanic and Atmospheric Administration.
(Luis Sinco / Los Angeles Times)
More than 1,000 marine mammals along the Southern California coast have gotten sick or died this month due to a bloom of toxic algae, according to the National Oceanic and Atmospheric Administration.
The Channel Islands Marine and Wildlife Institute, a local rescue organization, has logged hundreds of reports of dead sea lions and nearly 60 dolphins in the first few weeks of June, according to NOAA.
“We are managing more than 200 reports of marine mammals in distress each day,” Ruth Dover, co-founder and managing director of the organization, said in a news release. “We are doing the best we can to keep up with the intense pace. Please continue to report all sick and injured marine mammals as we are getting to as many animals as we can, as quickly as we can, each day.”
High concentrations of domoic acid — a neurotoxin produced by the marine algae Pseudo-nitzschia — have been found in waters from Orange County to San Luis Obispo County, according to forecasts by the NOAA and the Southern California Coastal Ocean Observing System. There are especially high concentrations around Ventura and Santa Barbara counties.
Ventura resident and photographer Kelly Nakamaru saw a dead dolphin last week at Ventura's popular surfing spot known as California Street or "C Street."
"My heart was so heavy," she said.
More than 1,000 marine mammals along the Southern California coast have gotten sick or died this month due to a bloom of toxic algae, according to the National Oceanic and Atmospheric Administration.
The Channel Islands Marine and Wildlife Institute, a local rescue organization, has logged hundreds of reports of dead sea lions and nearly 60 dolphins in the first few weeks of June, according to NOAA.
“We are managing more than 200 reports of marine mammals in distress each day,” Ruth Dover, co-founder and managing director of the organization, said in a news release. “We are doing the best we can to keep up with the intense pace. Please continue to report all sick and injured marine mammals as we are getting to as many animals as we can, as quickly as we can, each day.”
High concentrations of domoic acid — a neurotoxin produced by the marine algae Pseudo-nitzschia — have been found in waters from Orange County to San Luis Obispo County, according to forecasts by the NOAA and the Southern California Coastal Ocean Observing System. There are especially high concentrations around Ventura and Santa Barbara counties.
Ventura resident and photographer Kelly Nakamaru saw a dead dolphin last week at Ventura's popular surfing spot known as California Street or "C Street."
"My heart was so heavy," she said.
Dr. Alissa Deming, left, and veterinarian assistant Malena Berndt give anti-seizure medicine to a California sea lion named Patsy in a recovery room at the Pacific Marine Mammal Center in Laguna Beach after it was found having seizures from toxic algae blooms.
(Allen J. Schaben / Los Angeles Times)
On Sunday, Nakamaru called the Channel Islands institute when she saw that the dolphin was still on the beach but was told, "'We have dead seals and dolphins all over the beaches right now.'"
In fact, when Nakamaru was walking Tuesday morning on Ventura's Emma Wood State Beach she saw five more deceased dolphins washed ashore.
Sam Dover, executive director of the Channel Islands institute, said in an Instagram post that the institute was "currently inundated with domoic acid sea lions and dolphins."
“We are receiving 30-60 calls per hour and responding to over 30 animals per day," he said.
The algae tend to grow during spring and fall and under specific conditions, such as when an upwelling of water results in nutrients from deeper water rising to the surface where the sunlight is stronger, according to the Channel Islands institute. The toxin produced by the algae can cause brain damage, seizures and death in marine animals. The toxin doesn't affect humans unless they eat it in contaminated food.
Experts recommend that if you see a marine mammal exhibiting odd behaviors, such as swaying their head back and forth, seizure activity or foaming at the mouth, to keep your distance and contact the Channel Islands institute at (805) 567-1505 or online.
Algal bloom events have happened in Southern California in 2002, 2006, 2007, 2017 and 2022.
California sea lions are the ocean mammals most frequently exposed to domoic acid because of the location of their foraging sites and habitats, according to the Channel Islands institute. Pregnant sea lions, in particular, are susceptible because they tend to eat more food. Domoic acid can cause prenatal mortality, including stillbirths and death, as well as premature births.
With treatment, symptoms usually subside within 72 hours, and in many cases sea lions can recover. The toxin can damage the hippocampus region in the brain, resulting in memory loss and an inability to learn or retain information. The damage depends on how much contaminated fish a sea lion has consumed.
This story originally appeared in Los Angeles Times.
On Sunday, Nakamaru called the Channel Islands institute when she saw that the dolphin was still on the beach but was told, "'We have dead seals and dolphins all over the beaches right now.'"
In fact, when Nakamaru was walking Tuesday morning on Ventura's Emma Wood State Beach she saw five more deceased dolphins washed ashore.
Sam Dover, executive director of the Channel Islands institute, said in an Instagram post that the institute was "currently inundated with domoic acid sea lions and dolphins."
“We are receiving 30-60 calls per hour and responding to over 30 animals per day," he said.
The algae tend to grow during spring and fall and under specific conditions, such as when an upwelling of water results in nutrients from deeper water rising to the surface where the sunlight is stronger, according to the Channel Islands institute. The toxin produced by the algae can cause brain damage, seizures and death in marine animals. The toxin doesn't affect humans unless they eat it in contaminated food.
Experts recommend that if you see a marine mammal exhibiting odd behaviors, such as swaying their head back and forth, seizure activity or foaming at the mouth, to keep your distance and contact the Channel Islands institute at (805) 567-1505 or online.
Algal bloom events have happened in Southern California in 2002, 2006, 2007, 2017 and 2022.
California sea lions are the ocean mammals most frequently exposed to domoic acid because of the location of their foraging sites and habitats, according to the Channel Islands institute. Pregnant sea lions, in particular, are susceptible because they tend to eat more food. Domoic acid can cause prenatal mortality, including stillbirths and death, as well as premature births.
With treatment, symptoms usually subside within 72 hours, and in many cases sea lions can recover. The toxin can damage the hippocampus region in the brain, resulting in memory loss and an inability to learn or retain information. The damage depends on how much contaminated fish a sea lion has consumed.
This story originally appeared in Los Angeles Times.
21
Madeline Halpert - BBC News, New York
Wed, June 21, 2023
Toxic algal blooms are killing hundreds of sea lions and dolphins along the coast of California's southern beaches.
More than 1,000 marine animals have become sick or died in June, according to the National Oceanic and Atmospheric Administration (NOAA).
Experts say algal blooms pose a seasonal issue, but climate change may be worsening the problem.
Rescue groups are getting more than 200 reports of marine mammals in distress each day.
"I've heard of a number of people walking the beaches who have seen [sick] animal after [sick] animal," said David Caron, a biological sciences professor at the University of Southern California.
"Animal rescue groups are scrambling to try to get boots on the ground to get the animals protected."
Sea birds, dolphins and sea lions in particular are becoming ill from the rapid growth of certain species of algae, which produce a toxin called domoic acid.
Harmful algal blooms work by disrupting food webs, Dr Caron said. Creatures such as shellfish, anchovies and sardines consume the toxins before then being eaten by larger marine mammals.
"They eat a meal of those highly toxic fish and then they become toxified themselves, and if they get enough of that material, it of course can kill them, which is happening now," he said.
Santa Barbara and Ventura counties in Southern California have been hit especially hard, according to the NOAA.
The Channel Islands Marine & Wildlife Institute, which helps rescue and treat sick animals, said it was receiving more than 200 reports of marine mammals in distress each day.
"We are doing the best we can to keep up with the intense pace," institute co-founder Ruth Dover said in a statement.
When domoic acid affects marine mammals, they can become disoriented or even convulse and die under water.
The blooms can pose a danger to humans as well. People can become sick if they consume fish packed with the toxins, though the California Department of Public Health monitors for these levels and closes shellfish beaches when necessary, Dr Caron said.
Humans may also attempt to approach larger mammals like sea lions and dolphins if they see them stranded on the beach, but the animals may become aggressive because of the toxins.
People should avoid the marine creatures and call rescue organisations, which have been able to save some animals by capturing them, feeding them, and giving them liquids until they can flush the toxins out of their system, Dr Caron said.
Algae usually blooms between March and June in California, but the blooms may be peaking later this year because of its long and rainy winter.
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Experts say that not all species of algae produce harmful toxins, but the ones that do may be expanding to new areas because of climate change.
This is because as water temperatures rise, more areas become habitable for harmful algae blooms, which tend to form in warmer water.
Scientists are still working to untangle the effects of climate change on organisms living in coastal waters, Dr Caron said.
"But we have a fair amount of evidence, especially in inland waters, that climate change is exacerbating some of the problems that we're seeing with harmful algae," he said.
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