On their way to the Whirl Cup competition, Ash and friends are fortunate enough to pass a small mountain village just as an annual Chinchou migration is about to occur. Long ago seismological forces had combined to lift the mountain out of the depths of the sea, bringing along with it the undersea nesting ground of these Chinchou. Guided by instinct, these sea Pokémon continue to lay eggs there even though the land is now above water. Ash and friends join a father and son appointed this year by the village to protect the Chinchou on their journey—and it's a good thing these Pokémon Trainers were along because it turns out Team Rocket has designs on the migrating Chinchou as well.
S5 | Episode 1
Around the Whirlpool