Ginichi Y. Ohira, 50, is charged with knowingly selling a marine mammal product for an unauthorized purpose in violation of the federal Marine Mammal Protection Act.
Officials say thousands of anchovies and sardines have died in Ventura Harbor after using up all their oxygen.
The California Department of Public Health said on its website that traces of radioactive Iodine-131 was found March 28 in San Luis Obispo County.
Researchers from two local marine life groups say about a third of the fish collected in the northern Pacific Ocean had plastic in their stomachs.
It could take a week — and the smell could get pretty bad — before crews manage to scoop and vacuum up tons of dead sardines from a Southern California marina.