Sharks tend to be seen quite often in cartoons

Sharks are used in popular culture commonly as eating machines, notably in the Jaws novel and the film of the same name, along with its sequels. Sharks are threats in other films such as Deep Blue Sea, The Reef, and others, although they are sometimes used for comedic effect such as in Finding Nemo and the Austin Powers series. These comedic effects can sometimes be unintentional, as seen in Batman: The Movie and various Syfy channel films like Dinoshark and Sharktopus.
Sharks tend to be seen quite often in cartoons whenever a scene involves the ocean. Such examples include the Tom and Jerry cartoons, Jabberjaw, and other shows produced or created by Hanna-Barbera. They also are used commonly as a clichéd means of killing off a character that is held up by a rope or some similar object as the sharks swim right below them, or the character may be standing on a plank above shark infested waters