If my grandchildren were to look at me and say, 'You were aware species were disappearing and you did nothing, you said nothing', that I think is culpable. I don't know how much more they expect me to be doing, I'd better ask them.

I think we're lucky to be living when we are, because things are going to get worse.

The fact is that no species has ever had such wholesale control over everything on earth, living or dead, as we now have. That lays upon us, whether we like it or not, an awesome responsibility. In our hands now lies not only our own future, but that of all other living creatures with whom we share the earth.

One in eight plant species face extinction.

Being in touch with the natural world is crucial.

‎Using his burgeoning intelligence, this most successful of all mammals has exploited the environment to produce food for an ever increasing population. Instead of controlling the environment for the benefit of the population, perhaps it's time we controlled the population to allow the survival of the environment.

I often get letters, quite frequently, from people who say how they like the programmes a lot, but I never give credit to the almighty power that created nature.