Elusive Tree Kangaroo Spotted for First Time in 90 Years

The Wondiwoi tree kangaroo may summon up the image of a bouncing, long-tailed creature clumsily swinging through the forests with a bright-eyed, pouch-nestled baby in tow. But when biologist Ernst Mayr first spotted the marsupial in the mountains of West Papua, New Guinea, in 1928, he described it as more of a hybrid monkey-bear.

The Wondiwoi tree kangaroo proceeded to elude researchers for the next 90 years, prompting fears of its extinction. Then, this July, amateur botanist Michael Smith chanced upon a member of the species while exploring the dense thickets of the Wondiwoi mountain range. As John Pickrell writes for National Geographic, Smith's snapshots of the enigmatic kangaroo offer the first photographic evidence of the animal in its natural habitat and represent only the second recorded sighting of the species.

In an interview with his British hometown paper, the Alton Post Gazette, Smith explains that he and his team identified the animal as a likely member of the kangaroo species based on several distinguishing factors: scratch marks left by the creature’s giant claws (which enable them to climb trees), a “foxy” scent permeating the air, and scat, or kangaroo poop, dotting the ground.

The group spotted the kangaroo while hiking at a height of roughly 4,900 to 5,600 feet. As Smith tells National Geographic’s Pickrell, the animal itself was perched in a tree about 90 feet above the forest floor.

The Wondiwoi tree kangaroo is one of only 17 known species and sub-species of tree-dwelling kangaroos. Scientists’ sparse knowledge of the creature draws on the only specimen ever captured, a male shot and donated to London’s Natural History. According to the Tenkile Conservation Alliance, the male weighed about 20 pounds and was found at an elevation of 5,250 feet. His fur had a blackish underlying color but was frosted with silvery yellow tips, while his rump and limbs were reddish and his tail was almost white.

University of Melbourne zoologist Tim Flannery, author of Tree Kangaroos: A Curious Natural History, tells Pickrell that the distinctive coat coloring seen in Smith’s photographs leaves little doubt of the animal’s identification as a Wondiwoi tree kangaroo.

In an interview with the Huffington Post’s Sara C. Nelson, Flannery further explains that the species likely remained unseen for so long because its habitat is restricted to a small stretch of the Wondiwoi mountains. Pickrell adds, however, that the widespread presence of scratch marks and dung suggests the kangaroo “is amazingly common in a very small area.”

Flannery isn’t the only expert convinced of Smith’s find: As Pickrell reports, Smith reached out to a series of experts, including Australian Museum biologist Mark Eldridge and Roger Martin of Australia’s James Cook University, to confirm his suspicions before announcing them to the public.

Eldridge tells Pickrell that the Wondiwoi mountain range is “such a remote and difficult spot to access” that he was unsure whether scientists would ever find another member of the species. Martin seconds the sentiment, wryly noting, “Only an intrepid Pom [Brit] in pursuit of rhododendrons would have persevered.”

To further cement his discovery, Smith plans on importing collected tree kangaroo scat to the U.K. so it can be compared with DNA extracted from the 1928 specimen. Although Smith’s find suggests the Wondiwoi tree kangaroo has not been pushed to extinction as previously assumed, the species remains at risk. Poaching, as well as a planned gold mine set to overtake the montane region, both pose significant threats to the area’s wildlife.

“The tree kangaroo is walking a tightrope at the moment,” Smith tells the Alton Post Gazette, “[and] it could be genuinely extinct within a few years if things go wrong."

Meilan Solly | | READ MORE

Meilan Solly is Smithsonian magazine's senior associate digital editor, history.