Thank you so much for playing, and for your kind review! In retrospect, I agree it definitely would have been nice to introduce some factors out of the player control, so the player can proactively try to "fix" the situation (invasive species is an interesting idea!). An overpopulation situation was tossed around during development, but ended up being scraped in favor of keeping the game more streamlined and intuitive. Glad you enjoyed playing! :D