Which regions of the world have seen the greatest rates of mammal extinction? Surprisingly, it's not the Amazon rain forest nor the clear-cut forests of the U.S. or Africa's Serengeti plain.

Humans have harmlessly harvested coral reefs for thousands—or even hundreds of thousands—of years. So why has our behavior in recent years suddenly put reefs at risk?

Because they feed on everything from monkeys and pacas to armadillos and alligators, jaguars play a key role in the rain forest ecosystem. Learn how protecting them safeguards the jungles of Belize.

From a humble start 25 years ago tossing seed-filled water balloons into abandoned city lots, the Green Guerillas have grown into an organization that has created and maintains 1,000 urban gardens.

There are more than 260 distinct ecosystems in the United States. Yet only a little over half of them are in protected wilderness areas. What does it take to obtain "wilderness status"?

In the mid-1970s, only 100 of these parrots were left in the wild. Learn how an international effort more than tripled the St. Lucia parrot population in 20 years.

In a single century, the salmon population of Washington State's Elwha River shrunk by more than 99 percent. What caused this dramatic decline, and what can be done to turn it around?

In the world's largest tropical lake, Nile perch have eaten their way through all but one of their prey species, bringing the ecosystem close to death. But don't blame the perch—humans are at fault.

Around the world, habitats are being destroyed and people are turning away from ancient traditions. Balick is working to make sure that plant wisdom isn't lost in the process.

From acting on the Broadway stage to acting on her concerns about habitat destruction in Madagascar, Penelope Bodry-Sanders has had a wide-ranging and active career.