is one piece episode 575 filler?

Surrounded by a fleet of Marine battleships, the Straw Hats prepare to fight the overwhelming odds but Nami points out that they were actually mirages. She informs them that they are in the Maubeugemour Sea where dangerous weather phenomena occur and the Straw Hats are in the middle of it.

The Straw Hats managed to counter nearly everything the sea throws at them, from humongous rain drops which quickly turned into hail, from snowfall the size of an avalanche and even the very sea splitting into a gorge. After surviving the vicious sea, the Straw Hats enjoy a peaceful but hot day at sea.