Sharkigators, also called Pool Sharks or Sewer Sharks, were a dangerous species of killer fish native to the Solana Galaxy.
They also appeared naturally in the oceans on Rilgar and Pokitaru. If Ratchet falls into the water, he will quickly be devoured by one of these animals. They are also fought in the sewers, and can be killed if beached by the Hydrodisplacer.
On Kalebo III, after Ratchet uses the Hydrodisplacer to stop the flood at the Gadgetron Sponsored Hoverboard Race, several of these Killer Fish are beached in the Hoverboard Track.
As an environmental threat
Non-attackable Sharkigators were found throughout the Solana Galaxy and and were the creatures that ate anyone who decided to swim too far from land. They could be found lurking in the water on any level that did not require the player to swim, making the sharks act as a deterrent for players straying too far from anywhere else in the level besides the set path.
As an enemy
Sharkigators were encountered as fightable enemies in the sewers on Rilgar and Pokitaru that ate Ratchet only if he was in water. When the Hydrodisplacer is used to beach them, a single swing of the wrench would kill the enemy. These were the only times that the Pool Sharks could be attacked.