“People must feel that the natural world is important and valuable and beautiful and wonderful and an amazement and a pleasure.”

“It's coming home to roost over the next 50 years or so. It's not just climate change it's sheer space, places to grow food for this enormous horde. Either we limit our population growth or the natural world will do it for us, and the natural world is doing it for us right now.”

“All we can hope for is that the thing is going to slowly and imperceptibly shift. All I can say is that 50 years ago there were no such thing as environmental policies.”

“I don't run a car, have never run a car. I could say that this is because I have this extremely tender environmentalist conscience, but the fact is I hate driving.”

“Many individuals are doing what they can. But real success can only come if there is a change in our societies and in our economics and in our politics.”

“I think a major element of jetlag is psychological. Nobody ever tells me what time it is at home.”

“I like animals. I like natural history. The travel bit is not the important bit. The travel bit is what you have to do in order to go and look at animals.”

“Before the BBC, I joined the Navy in order to travel.”

“Dealing with global warming doesn't mean we have all got to suddenly stop breathing. Dealing with global warming means that we have to stop waste, and if you travel for no reason whatsoever, that is a waste.”