Sea lions are suffering brain damage from an algae bloom and while this algae is naturally occurring, this year it was the largest on record. Scientist have found that the toxin in the algae is impairing the sea lions’ brains and in some cases causing severe impairment and even death. Marine biologists scanned the brains of 30 sea lions and found damage in their brain’s hippocampus, which is the part of the brain that is used for navigation and memory.
According to DB Techno on December 15, this algae poisoning has caused neurological and behavior changes in sea lions after they were exposed to the domoic acid from the algae bloom. Emory University cognitive psychologist Peter Cook, who worked on the sea lion study while at the University of California-Santa Cruz said, “The behavioral deficits accompanying brain damage with domoic acid are severe, and may negatively impact foraging and navigation in sea lions, driving strandings and mortality.”
Cook also said, “Hundreds of sea lions end up in stranding facilities each year. A great many of them do die although some can be rehabilitated and survive for some time in the wild.” This latest study on the sea lions suffering brain damage from the algae bloom was published in the journal Science on Monday.
The algae is eaten by shellfish and small fish, so they contain the the toxin from the algae, which accumulates over time. Sea lions, other marine mammals and seabirds are exposed to it after eating those shellfish and fish, which is a main part of their diets.
According to News Max today, this toxin from the algae is not only causing brain damage but it is also responsible for some premature deaths of some sea lions. Brain damage in sea lions have been noted since the 1980 from this algae bloom, but for some reason the algae bloom has grown in leaps and bounds, which effects a larger part of the sea lion population. This year’s bloom was the largest on record, reaching from Santa Barbara, California to Alaska. This algae has covered a lot of area and much of this area is home to the sea lion population.
Cook said, “Domoic acid-producing blooms have been in the environment for a very long time, but the current pattern of much larger and more frequent blooms causing more visible damage to marine animals has been going on since the 1980s.” Scientists are in the process of investigating the increase of these algae blooms in both frequency and size. Today the scientist are leaning towards the cause possibly being associated with ocean pollution from fertilizers, as well as warming ocean temperatures. They have also mentioned a possibly link to global climate change.