Irreplaceable Wildlife Locations?

It comes to something when lists of 'irreplaceable' environments appear (http://www.theguardian.com/environment/gallery/2013/nov/14/top-10-irreplaceable-nature-reserves-in-pictures ) along with succinct reasons why they are unlikely to survive in the long term. I am somewhat reminded that I am probably watching Sikkim (voted the number one location in the world to visit by 'The Lonely Planet Guide' series and an acknowledged biodiversity hotspot) probably in the throws of permanent and dramatic change. An airport is being built making access to a country one third the size of Wales much easier and an array of hydroelectric schemes are being developed on its rivers (said to be capable of generating 200 Gigawatts of electricity- but most of it to be used elsewhere in India).