is one piece episode 765 filler?

As the Straw Hats, Wanda, and Carrot ride to the Whale Forest, Brook reveals that Pekoms had agreed to spare their crew from Big Mom's plan out of gratitude for them saving his people, but this proved to be his undoing as Capone Bege shot him and left him on the island. However, because of this, the Straw Hats could now gain information on Big Mom's location, and Luffy promises to get Sanji back from her.

As Usopp wonders what condition the lion mink is in, a swarm of yellow insects flies toward the group.