Tsuritama

In Enoshima, Yuki is a high school student who's never been good at making real friends thanks to his abnormally poor communication skills. Haru is the self-styled alien who decides to teach Yuki to fish. Natsuki is an irritable born-and-raised local. Akira is the mysterious Indian who watches them all from a distance. These four meet, fish, and find big adventures on their little island.

Synopsis from Anime News Network