A large monster with the brown head of a grizzly bear and a mottled green piranha body, the sea bear had fish-like flippers instead of arms, a long flappy dorsal fin and sharp claws. According to both the Bikini Bottom Inquirer and Fake Science News, there were a number of methods by which to attract the attentions of a sea bear, including playing the clarinet badly, waving a flashlight back and forth really fast (flashlights being their natural prey), stomping on the ground (they take that as a challenge), eating cubed cheese, wearing a sombrero in a goofy manner, wearing clown shoes or a hoop skirt, screeching like a chimpanzee, or simply running, limping or crawling. They could be fended off by drawing a perfect circle in the sand; the sea bear would then be unable to cross the line and to get to its intended victim.
Whilst out camping with SpongeBob and Patrick, Squidward, who did not believe in the existence of sea bears, did everything he could think of to attract one, seeking to prove to the pair that sea bears were not real. One of these monsters promptly showed up and proceeded to maul poor Squidward before he could take refuge in the protective circle drawn by SpongeBob and Patrick.
Unfortunately, the noise of the sea bear attack attracted the attentions of a Sea Rhinoceros which also attacked and mauled Squidward (but was unseen), who was not wearing his anti-sea rhinoceros underwear unlike Spongebob and Patrick.