Chopper earned his first bounty after the Enies Lobby Arc. The fact that the Marines gave who they think is the crew pet a bounty at all just goes to show the genuine impact of the Straw Hats ...

With this new bounty, Luffy has a much huger target on his back than ever before as the Straw Hats prove themselves to be a strong crew. It’s only up from here, really.

Simply put: the Straw Hats are the East Blue Pirate crew started by Monkey D. Luffy, who serves as the main protagonist of One Piece, with Luffy.