I don't think whole populations are villainous, but Americans are just extraordinarily unaware of all kinds of things. If you live in the middle of that vast continent, with apparently everything your heart could wish for just because you were born there, then why worry? [...] If people lose knowledge, sympathy and understanding of the natural world, they're going to mistreat it and will not ask their politicians to care for it.

The idea that the Lord had given us a present, that the world is a gift from God... well, the amount of stuff, back then, that the Lord was giving away was limited. We do not have dominion.

There is no question that climate change is happening; the only arguable point is what part humans are playing in it.

I believe the Abominable Snowman may be real. I think there may be something in that.

You've got to be fairly solemn [about the environment]. I mean the mere notion that there are three times as many people on Earth as there were when I started making television. How can the Earth accommodate them? When people, including politicians, set their faces against looking at the consequences-it's just unbelievable that anyone could ignore it.

Humanity is facing a very big, slow, long, drawn-out threat, and that is to do with the way the weather is changing and the size of the population.

I'm not an animal lover if that means you think things are nice if you can pat them, but I am intoxicated by animals.