Sea lions on the California coast are displaying strange behavior likely due to a harmful algae bloom impacting the region, according to marine researchers.

There's been a recent increase in the number of sea lions becoming sick along the California coast. Marine biologists say the cause is domoic acid, a neurotoxin found within algae blooms. Fish feed on those algae blooms, and sea lions who feed on those fish end up getting sick from the domoic acid in the fish they eat.

A California surfer was left injured and shaken after a violent sea lion attack, which experts believe was triggered by a toxic algae bloom.