In my starting place, a mountainous area, all insects died from dehydration. Nice to get all jelly, but probably not an intended mod result. Several hives gone, It was a true massacre.
I lost count of all mods but probably have some cave biomes installed as well. Water is present and my pawns can draw.

I assume every insect hive has its own restrictive zone, meaning they cant exit it unless to attack intruders i think? This might mean they will not draw water when thirsty.