As you approach Greatfish Isle, you will notice some oddities. Firstly, the game clock will change to night. Secondly, it will begin raining. Thirdly, the cloud above the island and the very shape of the island - well, islands! These alone should tell you one thing - you are too late.
The water spirit, Jabun, the carrier of Nayru’s Pearl, once lived here. Quite obviously, he has gone. Quill - remember the Rito postman? - swoops down to you. He confirms the obvious - this is the work of Ganondorf. However, Jabun is not dead; quite the opposite - he is at Outset, alive.
Quill recommends against staying too long, and follows his own example by departing. Before you leave, grab the Piece of Heart on the cliff side, then switch the wind to the north-east. We shall be going directly to Windfall. There is one island between the two, though. We can shortly visit.
There is little of interest here, except a Blue Chuchu. There are fifteen of these across the Great Sea, each only holding one Blue Chuchu Jelly. If you want to begin your collection early, stun the Blue Chuchu to stop its electric guard, then strike it. It should drop the Blue Chuchu Jelly.
As always, map the area. You won’t be coming back for some time for any necessary reason. When you are ready, set sail once more, heading to Windfall Island.