A water drop sounds like this …
… but that noise was made by a bird. (named at the end of the recording: XC148304 by Gary Stiles.)
It’s my favorite bird sound from Panama, made by a black-bellied wren (Pheugopedius fasciatoventris).
In his preferred habitat the wren is hard to see. Mostly black and brown, his white throat looks like a splash of sunlight from below.
But he’s easy to hear. When he really gets going he doesn’t sound like a water drop at all. This long melodious song (xeno-canto XC15653) was recorded by Don Jones on Semaphore Hill Road, the road to Canopy Tower.
The “water drop” is just a tiny snatch of song.
(photos from Wikimedia Commons; click on the images to see the originals. recordings downloaded from Xeno Canto; links provided to the originals)