Having some idea of the culprit, I looked up, and sure enough, there was a tiny bat hanging upside down from the tree canopy above me.
Ooops, I think I've been spotted! Here's the little bat taking a look down at me looking up at him.
Frugivorous bats are well-known dispersers of talisay seeds, so if you come across a talisay seedling with no mother plant nearby, this flying mammal could be your sower.
I've always wondered where the bats I hear flying around at night roost. Nice to know the garden is home to another wild animal.
(And yes, I scattered the pile of seeds after I took the photo... didn't want my mom finding about our furry friend. I don't think she would be pleased.)
UPDATE: My friend (and wildlife biologist) JC identified batty as Cynopterus brachyotis, lesser dog-faced fruit bat (common short-nosed fruit bat, lesser short-nosed fruit bat). And this weekend, when I checked, there were two of them! Hope they hang around (haha).