Dayton O. Hyde pets a horse. (Courtesy Running Wild Film 2013)

Dayton O. Hyde is a cowboy, an author and a conservationist. Originally from Michigan, he migrated west to Oregon as a teenager, where, eventually, he and his wife bought his uncle’s ranch and worked the land. In his early sixties, he decided to reinvent himself. Fascinated by the wild mustangs that roam much of the West, he grew despairing about federal round-ups that resulted in the slaughter of these wild animals. His solution, which he developed with single-minded dedication, was to buy a large ranch in the Black Wild Hills of South Dakota, establish a mustang sanctuary, and lobby the feds to deliver corralled animals from Nevada and elsewhere to his land rather than to the knacker’s yard.

Today, hundreds of the wild horses roam Hyde’s 13,000 acres of land. It is an epic environmental success story. Yet his sanctuary is now threatened by a uranium mine that, if it goes ahead, will, he contends, irreparably damage the aquifer upon which the sanctuary relies.

Hyde, who has long worked to save endangered species and to preserve the wilderness of the West, is involved in a long-shot battle against the mine, rallying his neighbors to oppose it.

Now eighty-eight years old, his story has recently been brought to the big screen, in the form of a documentary, Running Wild, by director Suzanne Mitchell. The film, which arrived in movie theaters earlier this month, was described by New York Times reviewer Anita Gates as “quietly grand.”

This interview has been condensed and edited for clarity.

Sasha Abramsky: What motivates you to continue fighting the good fight? You’re 88 years old. Why not relax?

Dayton O. Hyde:

I’m only 88 years old. There’s lots of time left. I have lots to do. Lots of things disturb me about what’s going on in the natural world. So I look forward to doing battle on my various causes, most of which have to do with nature and what we’re doing to the wildlife in the country.

What about horses? They clearly have a special place in your heart.

I had no horses in my life when I was a boy in northern Michigan. My uncle was a rancher in Oregon. He wrote a letter saying his crew had run in 30 wild horses and were in the process of training them. What kind of letter is that for a young boy if you don’t expect him on your doorstep? So I soon left home and went to Oregon and became a cowboy for most of my life. I felt so deeply about things happening in the natural world that I started writing about it, and wrote several books.

[He coughs. Then he says in explanation of his coughing:]

I’m allergic to horses. I’m allergic to everything there is to be allergic to.

Apart from being allergic, what do you feel when you see a horse?

Just intense love. I’ve grown up with horses now and trained lots of them and the worst thing about old age is I could no longer ride safely. I’ve got too much to do, though, to get hurt. One day, I had my horse saddled and was going to ride. I thought ‘if this horse stumbled and fell and I got hurt I’d no longer be able to fight the uranium miners.’ There were so many projects I had in the works, I thought it wasn’t worth the gamble that nothing would happen.

Let’s talk about the uranium mining. Why is this an issue you’ve turned into your own?

It concerns the water in the West. We live in an area of the Black Hills where there isn’t a lot of great water. And the uranium miners from Canada and China have decided to mine an aquifer than runs right under our ranch, and it’s the only water we have for 600 head of horses and 100 head of cattle.

They mine by drilling a hole down through the aquifer into the uranium beds, saturating the pure water with uranium, pumping it to the surface. They take the uranium out and put the arsenic and selenium and remnant uranium back into the hole, which pollutes the water and the aquifer. They claim they can clean it. To us it’s not worth the gamble, because if they can’t clean it then we can no longer run horses on our sanctuary. I’ve been going to the legislature, going to hearings, I’ve hired attorneys. We’ve got the public really behind us now. This is probably my last great fight, but I’m going to win this one. I’ll find a way. I’ve won other fights in my life that everybody thought were unwinnable.

The next war we fight is going to be over water in America. We’ve got a lot of young people helping. When I started there was a general apathy on the part of the public. Everyone was concerned with jobs and how the uranium mine would make them rich. But it’s only a 20-year project and then the mine is gone. Young people are realizing it’s nothing to build a lifetime of hopes and dreams on.

What kind of mobilization are you doing?

We do fund-raising. We do radio, television, everything we possibly can to be heard by the public, so they realize the seriousness of the water war that’s going on. There’s a history in our area of uranium mining. Wells have been left uncapped since the early 1950s. The tailings of the uranium mining are polluting the land. We have 13,000 acres in which there are 3 wells. Now every one of our wells has been declared unsafe for human drinking, because of the uranium pollution – dust from previous mining in the area. It makes me feel angry that man doesn’t take good care of this planet. They’re trading short-term gain for long-term loss, all in the name of making money.

You combine a cowboy persona with a philosophical/activist persona. How do you fuse the two?

D.H.: I am what I am. It’s easy to get angry about these things, because I care so deeply for the wildlife I’m going to fight for them. It’s a great cause for me. I think I’d like to have been born in the 1700s rather than where I am today.

Why the 1700s?

Because there were a lot of things in the land that hadn’t been fouled up yet. Everywhere you looked there were wild places filled with birds and animals. [Today] certain species, like deer, have done well. Other species are disappearing. We had a lot of marshes, sand hill cranes. I had a rescue permit from the Fish and Wildlife Service to gather damaged nests and save them and put them back into the wild. I rescued sand hill cranes that were fast disappearing from the ranch. My challenge was to find a way to save them for posterity. I came up with ideas that have helped save the whooping crane. There were once 14 birds left in the U.S. There are now 300. When I see cranes of any sort fly over, it makes me feel good that I helped.

What will your legacy be?

The books will go on; that’s why I don’t write magazine articles. I’m reading books written 100 years ago, 200 years ago, and they’ve obviously lived on in their effects. Pastures and Beyond, my latest book, will live on. Sandy, my story of helping the endangered species, seems to have a life of its own.

Sum up in one sentence what the land means to you?

I take it as a living thing.

What do you want audiences to take away from the movie about your life?

That one guy who cares deeply can really have a profound effect on curing whatever danger he’s tilting at. I just started a new life at 62, because there were still challenges un-won. Now I’m 88 and I’m making plans for another 10 years. I win one battle, I’ll start another one. There’s a lot that’s wrong with the world, and it takes all sorts of people to stop being apathetic.

Are you optimistic?

Well, I’m not very optimistic when I see a lot of bad things happening that concern me. I’m optimistic when I start each battle. But there are a lot of large issues that upset me, and I’m sure I’ll always find something to get mad about. Angry would be a better word.

What do you hope America will look like in another 100 years?

I hope that all people will be able to look out of their windows and see wild horses running. Wild horses are a symbol of freedom, a symbol of so much. To me they’re worth worrying about, worth saving.

Editor-in-chief Katrina vanden Heuvel writes that, one year after Superstorm Sandy, we ignore climate change at our own peril.