Last week, the International Union for Conservation of Nature (IUCN) released the 2011 edition of the Red List of Threatened Species. As with most reports of this nature, much of the news is grave (especially for one featured species whose decline may be partially attributed to human consumption). However, one species in this gallery illustrates that while mankind does sometimes destroy nature, our conservation efforts truly make a difference. Scroll down to discover the tragically beautiful animals which comprise some of our planet’s most endangered species. — Global Animal

Brian Handwerk, National Geographic

Smiling Tarsier has been labeled Critically Endangered
Siau Island Tarsier: Putting on a Happy Face? Photograph courtesy Geoff Deehan

Threatened by a volcano and bush-meat hunters, the Siau Island tarsier is among animal species newly designated critically endangered in the 2011 update of the International Union for Conservation of Nature (IUCN)’s Red List of Threatened Species, released last week.

The world’s most comprehensive inventory of the global conservation status of plant and animal species, the Red List classifies species into eight categories, ranging from “not evaluated” to “extinct.” A critically endangered species is defined as a species at extremely high risk of extinction in the wild.

The Siau Island tarsier, for example, inhabits only one small Indonesian island dominated by an active volcano.

“Depending on the magnitude of the eruption and the path of the lava flows, the population could be severely affected or even possibly disappear,” said Rebecca Miller, program officer for the U.K.-based Red List Unit.

The big-eyed primates also face immediate pressure from islanders who have both degraded nearly the entire tarsier habitat and hunted the animals extensively—wiping out perhaps 80 percent during the past decade.

“There are credible reports that the locals regularly eat them and may serve five to ten in a single sitting,” Miller said.

The Dwarf Salamander is one of the new critically endangered species
Dwarf Salamander: Facing Shrinking Chances. Photograph courtesy Todd Pierson

The Chuj climbing salamander, a species of dwarf salamander  from Guatemala, is another addition to the critically endangered category of the 2011 Red List.

The salamanders are found in a limited area of hardwood forest, much of which has been cut for farming and firewood. But local authorities are also working hard to protect a remaining stretch of forest where the amphibians still thrive.

“It’s a classic example of how humans impact biodiversity around the world,” Miller said. “We have the power to destroy—but also the power to protect.”

The Bog Turtle is a new addition to the list of Critically Endangered Species
Bog Turtle, Big Trouble. Photograph by George Grall, National Geographic

This tiny, critically endangered bog turtle, Clemmys muhlenbergi, is one of the world’s smallest, squeezing into a 3- to 4.5-inch (7.9- to 11.4-centimeter) shell. But the eastern-U.S. reptile represents a big conservation problem. Wetland development and drainage have drastically reduced suitable habitat for this and many other species around the globe.

U.S. turtles, like C. muhlenbergi, are far less threatened than their Asian relatives, but their fates are increasingly bound together: Asia’s appetite for turtles as food and the pet trade is harming turtle populations halfway around the world.

The Harlequin Toad was recently designated as an ICUN Critically Endangered Species
Harlequin Toad: One of Only Two Known. Photograph courtesy Alessandro Catenazzi

Nineteen new frogs, toads, and salamanders were added to the Red List this year, and eight are said to be critically endangered—including Peru’s harlequin toad.

Extensive surveys of the toad’s forest habitat in 2010 turned up only two individuals.

Amphibians are one of the hardest hit animal groups, with an estimated four in ten species at risk of extinction from threats including habitat loss, pollution, and disease.

The Arabian Oryx is Proof that Endangered Species Conservation Works
Arabian Oryx: Bounding Back. Photograph by Michael Nichols, National Geographic

In addition to the newly critically endangered species, the new Red List boasts a few bright spots. The future looks bright, for example, for the Arabian oryx, which not long ago nearly vanished forever.

The last wild antelope was shot in 1972. But captive breeding and reintroduction efforts have rebuilt a wild population of at least a thousand individuals—moving the animal from “endangered” to the less serious “vulnerable” category.

“This is proof that conservation really does work,” Miller said.

“If it’s intelligently designed and done well, it can really pay off, and we can see recovery of species that were on the brink of extinction.”