[Chazar]

I can sort of second this: I once conquered a water province with shark knights. I could only build one of them every other turn, but after building about a dozen, I would not get them anymore - and I suddenly realized that resources had dropped to zero...

However, I am having sloth3 and I cannot recall the initial scales, but that sea province is pretty well inside my territory and has a dominion score of 10. I definitely built some land castles around it later on...