One Piece Movie 03: Chinjuu-jima no Chopper Oukoku
English name: One Piece: Chopper Kingdom of Strange Animal Island
Genres: Action, Adventure, Fantasy
Type: Movie, Episodes: 1
Aired: Mar 2, 2002
Studio: Toei Animation
Source: Manga
Rating: PG-13 - Teens 13 or older
Synopsis:
The crew comes upon Crown Island where the animals can talk and they makes Chopper their new king. But there are human hunters there also looking for the legendary horns that will give the person who consumes it immense power. Luffy and friends must stop them from destroying this animal kingdom.

(Source: ANN)