PokéPark Fishing Rally DS (Game) - Giant Bomb

Though you may have never heard of this little app in the US, PokéPark Fishing Rally is a downloadable fishing minigame for the Nintendo DS, which was only available at the PokéPark in Japan.

List of Nintendo DS games - Nintendo DS Games

List of Video Games - Giant Bomb

Gyarados Games - Giant Bomb

Pokémon Games - Giant Bomb

Poliwag Games - Giant Bomb

Pokémon Card Database - Unified Minds - #35 Slowpoke

Fishing Derby (Game) - Giant Bomb

Pokémon Games - Giant Bomb

Accented Title Games - Giant Bomb

List of Nintendo DS games (J–P) - Wikipedia