they mark the spots where you can warp to later in the game. there is at least one in each section of the sea, and once you talk to their chief and get the thing that looks like a gba game, shoot the golden frogs to get the symbols you have to draw to warp.
You can get the bow from the Temple of Courage on Molida Island.
You can find the bow in the Temple of Courage on Molida Island in the south western sea.
If you are in Molida Island the second hideaway is in front of a palm tree.
in front of the second tree from the mailbox on molida island.
On Molida Island.
(it is located at molida island)
go on Molida island and dig in batween the palm tree closets to the path as u can
u dig just under the tree by the fishermans house [left of the house]
you hit her
molinda island is the island south of the gost ship fog
you give it to the mermaid girl in molida island
In front of a palm tree