A sea lion angry at being caught in a fisherman's net took its wrath out on one of the crew after being set free on the boat deck.
The distressed animal is hauled onto the fishing boat in a net, and crew members rush over to cut it free.
But as they do so, the sea lion clamps its jaws round a fisherman's shoulder and hurls him across the deck.
The crew's curious dog then also wanders over to see what's going on and is chased away by the animal baring its teeth.
The men eventually manage to hose the animal off their boat.
According to news.com.au, the video, shot in Russia, identifies the animal as a steller sea lion, a near-threatened species found off northern Pacific coasts from Japan to California.
The breed, also known as the northern sea lion, is the largest of the eared seals. It is inferior in size only to the walrus and the elephant seal.
Adult females measure 7.5 to 9.5ft in length, and weigh 530 to 770lb.
Steller sea lions are sometimes killed intentionally by fishermen, as they are seen as competitors and a threat to fish stocks. Killing sea lions is strictly prohibited in the US, Canada and Russia, but, in Japan, a fixed number are still removed annually, ostensibly to protect their fisheries.