This Feraligatr is a water-type Pokémon owned by an unnamed trainer who won the Whirl Cup competition.
Feraligatr was used in the final battle of the Whirl Cup against Trinity and her Golduck. They wanted to start the battle but Team Rocket interrupted it by stealing the award for winning the Whirl Cup. Feraligatr used Water Gun along with Golduck to blast Team Rocket off with some help of Ash Ketchum and Misty. After Team Rocket blasted off, the battle continued. Feraligatr most likely won from Golduck as Feraligatr's trainer won the Whirl Cup.