Here’s what the authors had to say about their amazing experience:

You left everything behind, went to Africa, and lived in some of the most remote places on the continent. What drove you to do that?

As young graduate students back in 1972, we heard a lecturer talk about how Africa’s wildlife was disappearing. We worked for several years, sold some of our wedding presents, and left with one-way tickets and backpacks to conserve African wildlife.

Your book is written on several levels. Tell us about that.

On the surface, Secrets of the Savanna is a true-adventure story of how we stopped officially sponsored ivory poachers, who were operating like a drug cartel in an untamed remote African wilderness. So it is a thriller as well as the story of a great win for wildlife and for local village people. But on another level the book reveals how much we learned about humans by studying social animals like elephants and lions — such things as risk taking in males and the genetic basis for girls having close female friends. Wild animals show us why we need our natal troops and a real home and what we lose when these basic social units are fragmented for whatever reason. This book is as much about people as it is about elephants.

How did you stop the poaching?

The carrot-and-stick approach. First we developed the stick by supplying destitute government game scouts with equipment, training, and transport so that they could capture poachers. But we realized that we could not stop the poaching unless we found alternative jobs for the poachers and villagers. Ivory smugglers organized like a drug cartel — including high-level corrupt officials, who made a lot of money from the sale of ivory — paid indigent villagers as little as ten dollars to kill an elephant. They yanked children from school and paid them a mere lump of meat to carry their contraband. A lot has been said about how commercial poaching adversely affects wildlife, but not much has been said about how it corrupts and demeans rural people and steals their future. We set up a program that offered jobs, training, loans, health care, improved agriculture, and education to the people in villages where poaching was rampant, so that they could have legal jobs that were safe and provided a better livelihood to their families. That was the carrot.

Did this stop the poaching?

Mark: Not for a long time. Eventually I had to adopt some unconventional techniques. With permission from the government I flew at night with an assistant who shot firecrackers at the poachers’ camps. The firecrackers were harmless, but the poachers didn’t know that. They made a loud bang and a flash of light when they exploded. Poaching decreased. But then I began finding poachers’ camps at night using night-vision goggles, a GPS, and a helicopter. I landed game scouts virtually anyplace and at any time. But flying at night without lights to avoid being shot was extremely dangerous. One very dark night I descended into a deep ravine without knowing it and struck some trees with my main rotor. I had quite a number of near misses.

When did the poaching finally get better?

It took about six years, but finally the fish farms we had helped villagers start began producing lots of fish, the millers made a profit, and the beekeepers produced honey. The villages had schools and better health care. When the United Nations enacted a moratorium on the trade in elephant parts in 1990, black-market ivory became nearly worthless. A man could make more money as a fish farmer than he could as a poacher. The poaching stopped. When we started, they were shooting a thousand elephants a year; in 1996 they shot none.

So the elephants were finally safe, but were you?

When we shut down the poaching completely, we put very powerful men as high up as the president’s office out of the illegal ivory business. Somehow they had to stop us. So one year while we were in the States on home leave, the paramilitary stormed our compound in town and our bush camp and put our staff under house arrest, including a Peace Corps worker who had been seconded to our project. They didn’t even bother to produce a counterfeit warrant. Officials from the American embassy and the British High Commission flew a plane to rescue our staff. There were some pretty tense days and nights, but eventually our staff was set free. A lot of our equipment was confiscated, though, and the ambassador warned that it was not safe for us to return. We thought we had lost the project and that poaching would flare up again.

What happened to prevent that?

This is where the real hero of this story comes in. Hammer Simwinga was the Zambian coordinator of our village work. When corrupt officials took over our project in the main village and seized the office, the fax, the phones, our bank accounts, the trucks, and even our mailbox, we could not get in touch with Hammer. The officials had taken his motorbike, so to keep the project going he walked to remote villages and encouraged the people not to lose their trust in our work and its ideals. With no revolving fund, he kept the project going on the strength of his character alone. He made no salary. Finally, we got a letter from him with a new postal address and sent him money to start over.

And how are things today?

Our project is twenty years old this year. We have helped more than twenty thousand rural Zambians. From the original fourteen villages, the project has been expanded to fifty-two. The people now make one hundred times more money than they did while poaching elephants. Food security has more than doubled, and malnutrition has been eliminated. Our Rural Health Care initiative is still the only health care program in most villages. Elephant poaching is nil. Hammer Simwinga still directs the project, and now he contacts us from the Internet Cafe in Mpika!

How did you study the elephants?

We darted one cow from each of sixteen herds and put radio collars on them. Mark would fly our helicopter — around trees and through canyons — to within ten feet above the elephant; the vet would hang out of the door and shoot it with an immobilization gun. We would sometimes mistakenly dart a cow with a calf. Baby elephants weight 225 pounds or more shortly after birth, and they often charged us. One calf stood on Mark’s foot and butted him in the stomach, flattening him. The other way we studied them was to calculate the ages of most of the population by measuring their footprints. To do this, I (Delia) walked most of the rivers of the park every year. I took off from camp with a tracker (the first one was an ex-poacher) and several carriers, and we would walk for days along the rivers in completely wild areas. Not once in all those years did we come upon another person.

What was the most exciting thing that happened during your walks to study elephants?

Delia: I always insisted on camping about eighty yards away from my team of trackers so that I could have some privacy. One night I was reading by the campfire and heard a noise. I looked up to see a lioness circling in the grass; she would not go away and was unafraid of me. That’s a bad sign. Eventually she came within about ten yards of me, so I shouted to the men, and they rushed over with flashlights. We moved my tent over to their camp.

You found yourselves in very stressful situations: poachers shooting at you, assassination attempts in your camp. How did your marriage survive this?

Delia: Well, frankly, our marriage almost didn’t survive the stress. Poachers often shot at Mark when he flew at night. He flew low level, in the dark, among the mountains. I thought he was taking too many risks. I finally set up my own camp some distance away. I think every woman should have her own camp. During those bad years, occasionally we would get together in some neutral and peaceful corner of the wilderness to enjoy a pod of hippos in a pool or a mountain peak. This kept us together, but it was not easy.

What are the secrets of the savanna?

We studied the social structures of wild animals for years — Kalahari lions, brown hyenas, and elephants — and in so doing left our own families and groups behind. What we learned was this: our natal troops are extremely important. It is not so much that the herd, troop, or pride is incomplete without all its members, but that the individual elephant, baboon, or human is incomplete without the group. When we live in a society of strangers, we lose a great deal: feelings of security, self-esteem, confidence, and a sense of home. In the modern world we have lost so much of this, but the elephants can teach us how to get it all back again.

Miss Leavitt’s Stars: The Untold Story of the Woman Who Discovered How to Measure the Universe by George Johnson (Atlas/Norton, $13.95)

Interesting topics to consider when reading:

At one point Powers describes how well, or not so well, he transitions back into American life during a visit to his fiancée. Leaving much unsaid, the passage still resonates with the author’s disillusionment and trepidation as new and old ways of life clash.

A source of frequent discussion throughout the book is the definition of aid. Powers and many of the people he meets during his stay in Liberia voice very different opinions concerning what entails giving aid, and the price tag attached to such aid.

A continuous thread in Powers’ memoir is the desire for Liberia to move away from dependency toward self-sufficiency and sustainability. This is often linked with having a “first world” culture, which becomes problematic when the Liberian culture is lost or sacrificed in the transition.

The Grandest of Lives: Eye to Eye with Whales by Douglas H. Chadwick (Sierra Club Books/UC Berkeley, $24.95)

Lonesome George: The Life and Loves of a Conservation Icon by Henry Nicholls (MacMillan, $24.95)