Shark

A shark in the game, Ice Fishing.

Sharks are a small part of the Club Penguin wildlife. They appear in the mini-games of Ice Fishing, Catchin' Waves, Jet Pack Adventure, Hydro Hopper, and Puffle Rescue.

Behavior

Sharks appear to be aggressive and will attack Penguins, Worms and puffles if they get close enough.

In Catchin' Waves, it will trying to knock you off in survival mode later in the game.
In Puffle Rescue , when youre playing blue puffle mode,sharks try to "kill" you.

In the real world, sharks were meant to live in warm water, not cold (at least the type of shark shown in Club Penguin, which is a Great White).
Rockhopper said there is a shark longer than his ship.
The shark in Hydro Hopper has lighter fins than the shark from Ice Fishing.
There was a rumor that the Silver Surfboard attracts sharks, but it was proven false when Aunt Arctic was asked in the Club Penguin Times.
In real life the only shark that lives in freezing water is the Greenland Shark.
In Club Penguin, the sharks have only 4 gill slits and 1 pair of underside fins, in real life they have 5-6 gill slits and 2 pairs of underside fins.
In games where the shark wants to "kill" you, they're attack plan seems that a large pack or group charges you all gradually, knocking you into the water, which then the sharks behind you attack and eat you.