Looking for fantasy books set in a marsh/swamp environment!

I recently read a supernatural horror called A Dark Roux by Blaine Daigle, that took place in Louisiana, and it was great.

Swamps are already filled with mysticism, adding fantasy elements to them just makes it so great, but I’m having a hard time finding any other stories on my own.

I’m thinking bayou mermaids, or maybe voodoo witches… anything with adventure and magick!

Any recommendations are greatly appreciated