Bucky was a young trainer who went to visit his grandfather. When he came back into town, everyone had a Dunsparce but him. As Ash, Misty, and Brock heard the story and wanted to help Bucky to catch a Dunsparce. They encountered one, who went away and was blasted along with Team Rocket. The heroes decided to find a new one, but Team Rocket captured all the other Dunsparce. The heroes defeated Team Rocket, allowing Bucky to capture Dunsparce using his Caterpie.
He tried to use it in a small contest with other Dunsparce, but Caterpie failed. Still, Bucky's Caterpie fought Dunsparce, allowing Bucky to catch it.