How lame does your island have to be named after a fruit? Cuba would be viewed a lot differently if it was called "Island of Grapefruit". Anyway, on to this card: it's not very good. If it could target any creature, it would be slightly better, but it would be pretty good if it tapped for a mana as well (but then it would be a better Maze of Ith). I think this is just too underwhelming. This would make it much more playable:
Island of Wak-Wak
T: Add 1 to your mana pool.
1, T: Prevent all damage dealt by target creature this turn. Island of Wak-Wak doesn't untap during its controller's next untap step.
Pros: Repeatable quasi-Chain of Silence
Cons: Only targets flying creatures, doesn't tap for mana
Note: Using wiki-fu, I found that a Wakwak is a Filipino vampire. Why wasn't the Island of Wak-Wak an island of vampires?!