Dolphins, seals and sea lions found dead on Central Coast beaches

June 14, 2023

By JOSH FRIEDMAN

Members of the public are finding numerous sick or deceased marine mammals on Central Coast beaches, raising concerns about ocean water quality and a harmful algae bloom. [KCOY]

Since mid-May, the Channel Islands Marine & Wildlife Institute (CIMWI) has been receiving calls about deceased dolphins, sea lions or seals. Residents have spotted dead marine mammals in areas including Haskell’s Beach in Goleta, Leadbetter Beach in Santa Barbara, Padaro Beach in Carpinteria and along Rincon Beach between Carpinteria and Ventura.

Over the last five days, CIMWI has been receiving daily reports of about 14 deceased or sick sea lions and 14 deceased or sick dolphins in Santa Barbara and Ventura counties.

Volunteers who live in the area have been checking the animals and seeing if the rehabilitation center on the Gaviota Coast can rescue them. The chances of saving the sick marine mammals are low.

Marine mammal experts have yet to determine causes of death, though Southern California scientists are sampling harmful algae. Recently, there has been a large amount of harmful algae in the channel, which is viewed as a warning sign.

Last year, dozens of sea lions became sick in Santa Barbara and Ventura counties after exposure to Domoic acid. Domoic acid toxicosis stems from harmful algae blooms, sometimes referred to as “red tides.”

Increased runoff and elevated water temperature can create a breeding ground for the algae to grow. Domoic acid comes from blue or green algae and enters marine mammals through the fish they eat.

The poisoning can cause disorientation, erratic behavior, head weaving and can lead to seizures. When detected early, workers can flush out the toxins. If the exposure to the toxin is irreversible, it can damage a marine mammal’s brain.