Wondiwoi Tree Kangaroo: The Rare Species Rediscovered After Nearly 90 Years

VERIFIED: The rediscovery of the Wondiwoi tree kangaroo (Dendrolagus mayri) is a documented wildlife story. The species was known from a specimen collected in 1928 before a live animal was photographed in the Wondiwoi Mountains of West Papua in 2018. The rediscovery showed that the species had survived despite decades without a confirmed scientific observation.

The Wondiwoi tree kangaroo is one of the least-known mammals of New Guinea. For decades, scientists had no confirmed observation of the species after the original 1928 specimen. Then, in 2018, photographs taken in its remote mountain habitat provided compelling evidence that the animal was still alive.

The rediscovery became an important reminder that species living in remote and difficult-to-survey habitats can remain hidden from science for decades.

The Wondiwoi Tree Kangaroo at a Glance

• Scientific name: Dendrolagus mayri
• Common name: Wondiwoi tree kangaroo
• Location: Wondiwoi Mountains, West Papua, Indonesia
• Habitat: Montane forest
• Known scientific specimen: Collected in 1928
• Rediscovered: Photographed alive in 2018
• Conservation concern: Critically Endangered

The First Scientific Record in 1928

The story of the Wondiwoi tree kangaroo goes back to 1928, when evolutionary biologist Ernst Mayr collected the specimen that became the basis for the species' scientific recognition.

The animal came from the Wondiwoi Peninsula in what is now West Papua, Indonesia. The specimen was later formally described as Dendrolagus mayri.

The known specimen came from montane forest at roughly 1,600 meters above sea level. Its distinctive appearance included dark fur with lighter tips, reddish coloration on parts of the body, and a pale-looking tail.

Why Was the Species Missing for So Long?

The Wondiwoi Mountains are rugged and difficult to explore. Dense vegetation, steep terrain and remote montane forests can make wildlife surveys extremely challenging.

National Geographic reported that the 2018 expedition encountered dense bamboo forest and worked at elevations of roughly 1,500 to 1,700 meters, where signs of tree kangaroo activity began appearing.

Because there were so few scientific surveys focused on the species, the absence of observations did not necessarily prove that the Wondiwoi tree kangaroo had disappeared.

The 2018 Rediscovery

The breakthrough came in July 2018, when British amateur botanist Michael Smith led an expedition into the Wondiwoi Mountains.

Smith had originally been interested in rare plants, including rhododendrons. During the expedition, the team searched areas of montane forest where local information and earlier clues suggested that a tree kangaroo might still survive.

The expedition team included Papuan porters, a local hunter and Norman Terok, a student from the University of Papua in Manokwari.

As the team climbed into higher forest, they found signs that suggested tree kangaroo activity, including scratch marks on tree trunks and droppings.

Then came the crucial moment.

On one of the final days of the expedition, a tree kangaroo was spotted approximately 30 meters above the ground. Smith managed to photograph the animal through the vegetation.

The photographs were subsequently examined by experts in tree kangaroos. The animal's coloration and physical characteristics were considered consistent with the original description of Dendrolagus mayri.

National Geographic reported that the photographs represented the first confirmed images of a living Wondiwoi tree kangaroo in the wild after the species had gone undocumented for decades.

What Does the Wondiwoi Tree Kangaroo Look Like?

The species is a medium-sized arboreal marsupial with a distinctive dark coat. The original specimen was described as having blackish fur with lighter, yellowish or silvery tips, reddish coloration around the limbs and rump, and a pale tail.

Because the species has been observed so rarely, scientists still know very little about how much physical variation exists among individuals.

Where Does It Live?

The Wondiwoi tree kangaroo is associated with the remote Wondiwoi Mountains of West Papua, Indonesia.

The 2018 expedition reached montane forest at approximately 1,500 to 1,700 meters above sea level. Dense bamboo and steep terrain make this habitat particularly difficult to survey.

What Do Scientists Know About Its Biology?

Very little is known about the Wondiwoi tree kangaroo compared with better-studied kangaroo species.

• Arboreal lifestyle: It is adapted for movement in trees, using strong limbs and claws for climbing.
• Montane habitat: The known records are associated with high-elevation forest in the Wondiwoi region.
• Diet: The species-specific diet remains poorly documented.
• Population: There is no reliable modern population estimate.
• Reproduction: Detailed information about breeding and offspring remains limited.
• Behavior: Its behavior in the wild is still poorly understood because direct observations are extremely rare.

It is therefore important not to present detailed assumptions about its diet, population or behavior as established facts.

Conservation Status

The Wondiwoi tree kangaroo has long been associated with the highest levels of conservation concern. Historical IUCN records classified Dendrolagus mayri as Critically Endangered, Possibly Extinct (CR(PE)).

However, the 2018 photographic rediscovery demonstrated that the species was still surviving in the wild. That is why the rediscovery is better described as evidence of survival rather than a recovery of a known healthy population.

The species remains extremely poorly known, and the absence of a reliable population estimate makes conservation planning difficult.

What Threatens the Species?

Because the species is so poorly studied, the exact scale of individual threats is difficult to quantify. However, habitat disturbance and pressures affecting New Guinea's forests are important conservation concerns.

Habitat Loss

Logging, mining and agricultural expansion can threaten forest ecosystems. Protecting the montane forests associated with the species is therefore an important conservation priority.

Hunting

Hunting is a major threat to several tree kangaroo species in New Guinea. The Wondiwoi's remote high-elevation habitat may provide some protection, but the impact on this species remains poorly quantified.

Extremely Limited Knowledge

Perhaps the greatest challenge is the lack of reliable information. Scientists do not yet know the species' population size, complete distribution, reproductive rate or long-term population trend.

Why the 2018 Rediscovery Matters

The rediscovery of the Wondiwoi tree kangaroo is important for more than its novelty.

First, it demonstrates that remote forests can still contain species that are extraordinarily difficult to document.

Second, it provides researchers with an opportunity to investigate the species while there is still evidence that it survives.

Finally, the story highlights the importance of continued biodiversity surveys. A species missing from scientific records should not automatically be assumed to be extinct, particularly when its habitat is remote and poorly surveyed.

What Scientists Still Need to Discover

• How many Wondiwoi tree kangaroos remain?
• How large is their current range?
• Are there multiple breeding groups?
• What is their exact diet?
• How often do they reproduce?
• What habitats are essential to their survival?
• What are the most significant threats to the remaining population?

Future surveys could potentially use camera traps, environmental DNA, genetic material from naturally collected samples, and other non-invasive methods to learn more about the species.

The Rediscovery Was Not the End of the Story

Finding the Wondiwoi tree kangaroo in 2018 did not suddenly make the species easy to study.

In fact, its continued elusiveness is part of what makes the animal so remarkable. The species occupies remote mountain forests where fieldwork can be physically demanding and expensive.

The 2018 photographs therefore remain especially important because they provide direct visual evidence that the species survived after decades without a confirmed scientific observation.

Frequently Asked Questions

Is the Wondiwoi tree kangaroo real?

Yes. Dendrolagus mayri is a recognized species, and a living individual was photographed in the Wondiwoi Mountains in 2018.

Was it really missing for 90 years?

There was approximately a 90-year gap between the 1928 scientific specimen and the confirmed 2018 photographic observation.

Was the species declared extinct?

It was considered possibly extinct because there were no confirmed observations for decades. However, the 2018 photographs demonstrated that it had survived.

Where is the Wondiwoi tree kangaroo found?

It is associated with the Wondiwoi Mountains of West Papua, Indonesia, on the island of New Guinea.

How many Wondiwoi tree kangaroos are left?

There is currently no reliable population estimate. The species is extremely poorly known, which makes determining its population size difficult.

What does it eat?

The species-specific diet has not been adequately documented. It is safer to say that its feeding ecology remains poorly understood rather than treating assumptions based on other tree kangaroos as confirmed facts.

Why is the species important?

The Wondiwoi tree kangaroo is important because it represents a highly distinctive and poorly understood part of New Guinea's biodiversity. Its rediscovery also demonstrates why remote ecosystems require continued scientific exploration and protection.

Conclusion

The Wondiwoi tree kangaroo disappeared from scientific observation after a specimen was collected in 1928. Nearly nine decades later, photographs taken in the remote mountains of West Papua provided compelling evidence that the species was still alive.

The rediscovery was an extraordinary moment for wildlife science, but it should not be mistaken for proof that the species is secure. Scientists still know remarkably little about its population, reproduction, distribution and ecology.

The real conservation goal is not simply to find another photograph. It is to understand the Wondiwoi tree kangaroo well enough to protect the forests it depends on and ensure that this elusive marsupial does not disappear from scientific records — or from the wild — again.

Sources

• National Geographic — Rare Tree Kangaroo Reappears After Vanishing for 90 Years
• Smithsonian Magazine — Elusive Tree Kangaroo Spotted for First Time in 90 Years
• Re:wild — Lost Species / Rediscovery information
• Tenkile Conservation Alliance — Wondiwoi Tree Kangaroo
• IUCN Red List of Threatened Species

Editorial status: Verified and fact-checked. The 2018 rediscovery is documented by National Geographic and other credible sources. Claims about the species' current population size, reproduction and detailed ecology remain uncertain because the animal is exceptionally poorly studied.