Aloha

My forum senses were tingling, so I figured I'd drop in and see what was up, lol.
It looks like damage done by slugs and snails like Pueokai said. I think there might be too much damage to have been done by the caterpillars, and they don't normally feed in that pattern (at least most often they don't).
We had a Noni tree on North Shore that had this same damage all of the time, I looked day and night, never saw any caterpillars, but I often found slugs and snails halfway up the fence that it grew next to. They stayed up under the framework in the shade during the day, in under the foliage; an easy slime trail away from the leaves.
I also noticed alot of Katydids on them, if those are present you should be able to hear and or see them at night (you know, that loud, and rather obnoxious, buzzing you hear at night) Not sure, but these may be feeding on the Noni leaves as well.
Hope ya find out what it is, I'd definitely lay out a beer dish if you can, the snails and slugs get to everything eventually, got a bunch of my seedlings the other day, first time in 8 months they've dared to venture up the table, it's on....Lol. If nothing else, I've got another little something else in the works that might help ya out, will let you know if it works out well for me.

Hope this helps even a little bit, take it light and talk with ya later on, an' gimme a shout if ya get the chance Pueokai,

Aloha,
~D