In the past century, populations of wild tigers have plummeted from 100,000 to 3,500. Now the World Bank and conservationists have launched an eleventh-hour effort to save this great predator, focusing on reining in the black market for tiger parts and ending the destruction of tiger habitat.

With large swaths of forest destroyed by wartime defoliants, and even larger areas lost to post-war logging, Vietnam has set an ambitious goal for regenerating its woodlands. But proponents of reintroducing native tree species face resistance from a timber industry that favors fast-growing exotics like acacia.

The number of salmon in the Pacific Ocean is twice what it was 50 years ago. But there is a downside to this bounty, as growing numbers of hatchery-produced salmon are flooding the Pacific and making it hard for threatened wild salmon species to find enough food to survive.

Last spring, conservation groups and timber companies signed an historic agreement to protect a large swath of Canada’s boreal forest. In an interview with Yale Environment 360, the Pew Environment Group's Steven E. Kallick, a key player in the agreement, explains why the accord is integral to a larger plan to eventually preserve half of Canada’s extensive boreal forests.

When officials gather for an international summit on biodiversity next month, they might look to remind the world why species matter to humans: for producing oxygen, finding new drugs, making agricultural crops more productive, and something far less tangible — a sense of wonder.

Across the Far North, populations of caribou — an indispensable source of food and clothing for indigenous people — are in steep decline. Scientists point to rising temperatures and a resource-development boom as the prime culprits.

In the early 20th century, Russian botanist Nikolai Vavilov created a preserve outside St. Petersburg that today contains one of the world’s largest collections of rare seeds and crops. Now, scientists and conservationists are waging an international campaign to save the reserve’s fields from being bulldozed for housing development.

As Scotland asserts its identity and its autonomy,
environmentalists are working to restore its denuded landscape, planting native forests, creating wildlife corridors, and reintroducing species that were wiped out centuries ago.

The freshwater eel, which spawns in the middle of the ocean, was once abundant in much of the world. But the proliferation of dams, coastal development, and overfishing have drastically reduced eel populations, with few defenders coming to the aid of these fascinating — though still not fully understood — creatures.

Coffee production has long been vulnerable to drought or excess rains. But recently, a tiny insect that thrives in warmer temperatures — the coffee berry borer — has been spreading steadily, devastating coffee plants in Africa, Latin America, and around the world.

The Yangtze has been carved up by dams, used as an open sewer, and subjected to decades of overfishing. Now, Chinese scientists — alarmed by the disappearance of the Yangtze river dolphin and other creatures — are calling for a 10-year moratorium on fishing in the world’s third-longest river.

The Gulf of Mexico’s capacity to recover from previous environmental assaults — especially the 1979 Ixtoc explosion — provides encouragement about the prospects for its post-Deepwater future. But scientists remain worried about the BP spill's long-term effects on the health of the Gulf and its sea life.

As warming intensifies, scientists warn, the oxygen content of oceans across the planet could be more and more diminished, with serious consequences for the future of fish and other sea life.

Environmentalists in the U.S. are increasingly trying to use the Endangered Species Act to ease the impact of global warming on numerous animals and plants, including the American pika. The goal is not only to protect the habitat of at-risk species but also to force reductions in greenhouse gas emissions.

The polar bear has long been a symbol of the damage wrought by global warming, but now biologist Andrew Derocher and his colleagues have calculated how long one southerly population can hold out. Their answer? No more than a few decades, as the bears’ decline closely tracks that of the Arctic’s disappearing sea ice.

Primatologist Patricia Wright has spent the past 25 years studying — and protecting — Madagascar’s rich yet highly threatened biodiversity. Now, as many of the island’s remaining forests are being felled in the wake of a 2009 coup, Wright describes how she is helping organize the local residents and international conservation organizations to fight back.

Large corporations, not small-scale farmers, are now the major forces behind the destruction of the world’s tropical forests. From the Amazon to Madagascar, activists have been directing their actions at these companies — so far with limited success.

The images of pelicans and other Gulf of Mexico seabirds drenched in oil have stirred sadness and outrage around the world. But, says conservationist Melanie Driscoll, the unseen effects are probably far greater, with some birds perishing out of sight, far from shore, and others facing spill-related declines in the fish on which they depend.

A prominent marine biologist says the impacts of the oil gushing into the Gulf of Mexico will persist for years, no matter when the flow finally stops. What’s more, scientist Thomas Shirley says that most of the damage remains out of sight below the surface, as creatures succumb to the toxic effects of the rapidly spreading tide of oil.

Among the natural treasures at risk from the oil spill in the Gulf of Mexico is the Breton National Wildlife Refuge, created by Theodore Roosevelt to halt a grave threat to birds in his era — the lucrative trade in plumage. Now, oil from the BP spill is starting to wash up on beaches where Roosevelt once walked.

The chairman of the Intergovernmental Panel on Climate Change acknowledges it has been a rough few months for his organization. But, he argues, no amount of obfuscation and attacks by conspiracy theorists will alter the basic facts — global warming is real and intensifying.