Anchor and Chum are the Hammerhead and Mako sharks, respectively, from the 2003 Pixar film, Finding Nemo. Along with Bruce the Great White Shark, they are fish-eaters who want to get rid of their bad reputation, and think they can do so by treating other fish as friends, not food. (What will they feed on if not on fish is never revealed).
Despite their good intentions, they seem to have lots of trouble supressing their predatory instincts, although they do show a stronger will force than Bruce, who goes berserk as soon as he smells blood. Anchor and Chum try to stop Bruce from eating Marlin and Dory when this happens.
They reappear at the end of the film, completely reformed.
Although they only appear for a short while, Anchor and Chum are shown to dislike dolphins (whom they seemingly consider to be fish), and to love jokes. Chum, the Mako shark, also has a fishing hook on his nostril, suggesting that he escaped from being killed by a trophy fisherman. (Mako sharks are among the most sought after trophies among sharks).