15 Chapter 134 and Episode 81, Chopper makes his debut.

What season does chopper appear in One Piece?

The third season of the One Piece anime series, subtitled Enter Chopper at the Winter Island on home video, was produced by Toei Animation, and directed by Konosuke Uda based on Eiichiro Oda's manga by the same name. The third season deals with the Straw Hat Pirates trying find a doctor after Nami falls sick.

How did chopper join the crew?

5 Chopper Remembers His Mentor's Wish

Chopper is the crew's doctor, and he dreams of one day becoming a doctor who can cure any disease. ... The crew met Chopper on Drum Island, and when Nami invited him to join them he refused due to his mistrust of humans.