From a screenshot slideshow I found on Youtube with screens from 1999, here are two from underwater in Oasis that show there were a LOT more crocs under the water than above it. I would even say the majority of crocs in Oasis were under the water.
Dates on these pics are sometime a bit after October 1999 (the Oct 1999 halloween event with Lanys T`Vyl comes along a little earlier in the slideshow).
https://youtu.be/akdgif0QOkQ?t=296
https://youtu.be/akdgif0QOkQ?t=295