is one piece episode 509 filler?

Zoro wakes up at Mihawk's castle where Perona is crying over Gecko Moria's death. Mihawk is annoyed by her crying and tells her that Moria's death may not be for real as when he left the Summit War of Marineford, Moria was still alive.

Zoro then asks Mihawk if he knows more about Luffy as well as a way to get off the island. Mihawk answers with that he does not know anything more about Luffy and tells Zoro that there is a boat he could use to escape the island.

Zoro is then seen dragging the boat through the forest, and after a while, the humandrills come to attack, as Zoro expected.