An online video that apparently shows a man throwing an explosive into B.C. waters teeming with sea lions is generating online outrage — on both sides of the issue.

The video was posted on the Facebook page of the Pacific Balance Pinniped Society, a group of sport, commercial and First Nations fishers who aim to protect B.C. fish stocks by culling seals and sea lions.

According to video poster Thomas Sewid of Victoria, the video depicts a man throwing a bear banger into the water to scare the sea lions away from a boat that was taking samples of local herring stocks to measure roe percentages.

"Theoretically darkness brings the herring to the surface, which makes it easier to catch them," Sewid wrote. "This massive amount of sea lions diving on huge schools of thousands of tons of herring scares them to stay deep. This makes it so captains cannot catch herring, for they're too deep for nets."

The sea lions scatter as the explosive detonates, though none appear to be injured by the blast.

In response, Fisheries and Oceans Canada tweeted Thursday that it is illegal to disturb seals and sea lions, and asked the public to report any disturbances to the authorities.