Student or Learner
Rainfall decreased, rivers and lakes evaporated, vegetation disappeared and famine and drought took hold. Farming was impossible, and the lack of water made hunting treacherous. As a result, there was a mass exodus of animals and people from the region.
--- I don't understand why hunting became "treacherous"? What does it have to do with hunting?
The only thing I can think of is that the lack of available fresh water made textended hunting trips dangerous. (But if the animals had all fled, why bother at all )