I love people who have died trying to save wildlife. When I see that passion, that gives me hope.

We are not far away from the point of no return when it comes to life on earth, and we have some radical choices to make.

Whether it's exploring the woods around where I grew up, or even today exploring the coastal habitats and environments where I live in New England, or in a remote wilderness we're featuring in one of my series - I love to be in the field and I love to explore.

I'm glad I'm inspiring somebody.

Our health as a society, our robustness as a community, as a nation, as a people, is not only dependent upon fiscal stability, military might, political strength - it's also dependent on a healthy planet.

Many scientists would argue that we are now in what is called Extinction, and it's caused by this perfect extinction storm: climate change, habitat loss, pollution, unsustainable exploitation of species and habitat resources, and of course, human population explosion. All of these factors work together and conspire to drive a species to extinction on our planet, every half an hour.

I'm really worried about what the world is going to be like when my daughters are young women, [when] they are young leaders or mothers or businesspeople - whatever they're going to be. I'm afraid they're going to have a less healthy and less biologically rich planet.