Treasure map is an item found in the Message in a bottle on Goshima. Talking to Quartermaster Gully with this item in inventory allows the player to travel to the previously uncharted island of Agar Atoll. Players can talk to Salmon Ella to receive one taijitu.
The message in a bottle that contains this treasure map is currently visible. (wrong?) Once a message in a bottle is found and when a player has walked near its spawn location when it was visible it will always be visible, unless the message in the bottle or its treasure map is in the player's bank or inventory.
Max? Where are you, sweetie?
Hurry back, dear. I miss you.
I've included my coordinates, just in case you've lost them. See you soon.
Love and huggles,Ella