Monterey Bay Whale Watch said more than 10 balloons were found off the Santa Cruz coast when staff went out on a research survey Sunday.
The company said they found Mother’s Day, graduation, and heart-shaped balloons.
The company said the balloons and other debris can be dangerous to marine life because if they are eaten, they can cause blockage, starvation, or death.
Monterey Bay Whale Watch said they could also break down into microplastics that can affect the entire food chain.