Kookaburra sits in the old gum tree.
Merry little king of the bushes, he.
Laugh, kookaburra. Laugh, kookaburra.
Gay your life must be.
There is also this variant:
Kookaburra sits in the old gum tree.
Eating all the gum drops he can see.
Stop, kookaburra!
Stop, kookaburra!
Leave some there for me.