Not too often that you see a nature documentary dedicated to North American flora and fauna, so this episode was a real treat! While I could have done without the interviews with the people, the rest of the documentary was spot-on! The underwater cave shots were so beautiful and has made me look into booking a vacation up there! I had no idea about the greater Niagara ecosystem, it was fascinating to learn about. The cliff ecosystem was also suprising, as I had not heard about them previously. All in all, this was a terrific episode that continues the wonderful string of episodes for Nature this season. Just wish more people watched them, these are just as good as the BBC documentaries!