What You Should Know About California’s Toxic Algae Bloom

Thousands of dead fish, sea lions, and dolphins have been washing up on California beaches in recent weeks. Experts say the cause is toxic algae. The aquatic plant produces a neurotoxin known as domoic acid. Small fish such as anchovies feed on that algae and are then consumed by larger animals like dolphins or sea lions. These animals experience neurological symptoms such as seizures before succumbing to death.

Toxic algae blooms are not unusual, but this event is particularly severe.

“I have never seen anything this intense in terms of the numbers of animals in my 20 years of responding to strandings in this area,” Michelle Berman Kowalewski, founder and Director of the Channel Islands Cetacean Research Unit, told NOAA

Which areas are affected?

Most of the Southern California coast has been impacted, from Orange to San Luis Obispo counties. The highest concentrations of toxins and deaths have been found in the counties of Ventura and Santa Barbara.

Can it hurt humans?

Domoic acid can make humans sick if they eat contaminated food. Symptoms of domoic acid poisoning in humans include vomiting, diarrhea, and abdominal cramps. However, shellfish, crustaceans and other seafood are regularly tested for domoic acid to prevent illness.

Can it hurt pets?

Toxic algae blooms pose a significant risk to pets, particularly dogs. Exposure can occur if a dog eats affected algae, foam, or a contaminated animal. Exposure can also occur if a pet licks themselves after swimming in contaminated water.

Experts say pets should be kept out of water where toxic algae is known to be an issue, and should be kept away from any animals that appear to be experiencing neurological symptoms. If you suspect your pet has been in contaminated water, wash them immediately.

Signs of domoic acid poisoning in dogs include vomiting, lethargy, seizures, and loss of equilibrium.

Read more about California’s toxic algae bloom here