A new study outlines where Javan leopards live – and where suitable habitat remains on the densely inhabited island.

National parks remain the most stable habitat for the critically endangered species, but the study finds that half its potential habitat is in unprotected areas.

Partnering with companies and local people is necessary to keep Java’s last big cat from going extinct.

The big cats of Java haven’t had it easy. First to vanish was the Sunda clouded leopard, a small species that today survives only on Borneo and Sumatra. Next to go was the Javan tiger, last glimpsed slinking through Meru Betiri National Park in 1976. Today, the Javan leopard (Panthera pardus melas) is the only big cat left on the Indonesian island. Although it’s one of the rarest felids on the planet, a new effort to map leopard whereabouts could direct efforts to save the island’s largest surviving predator.

Employing 228 confirmed leopard sightings as well as information on environmental conditions, the recent study published in the journal PLOS ONE provides the most reliable information to date of where Javan leopards are likely to be found on the island.

“The worrisome situation is that leopards mostly live in heavily isolated, unsustainable, small landscapes,” said lead author Hariyo Tabah Wibisono, from the San Diego Zoo Institute for Conservation Research.

Leopards first reached Java from the Asian mainland via a now underwater land bridge some 600,000 years ago, more than half a million years before modern humans set foot on the islands that now make up the Indonesian archipelago. Isolated by rising seas, they evolved into a unique subspecies, genetically and morphologically distinct from all other Asian leopards. But this natural diversity is in grave peril of dying out.

Alongside the Amur and Arabian leopards, the Javan leopard is the only leopard subspecies listed as critically endangered on the IUCN Red List — the final rung of the ladder before the descent into extinction. After weathering the cataclysmic eruption of the Toba supervolcano 74,000 years ago, Javan leopards are now struggling against the fallout from a very different kind of boom: human population.

No one knows exactly how many leopards survive on Java today. In 2013, scientists estimated a population ranging from 491 to 596, but a 2016 assessment by the IUCN put the number at fewer than 250 mature animals. Even if the population is around 500, including juveniles, that would mean that for every leopard alive on the island today, there are more than a quarter of a million people.

“Our study found only a few conservation areas on the island which might have the capacity to support viable Javan leopard populations,” he said.

These potential leopard hotspots include several of Java’s national parks: Meru Betiri in the east —the final stand of the Javan tiger — and Ujung Kulon on its westernmost tip both retain enough suitable habitat to support more than 50 leopards each. Only Gunung Halimun Salak in the mountainous west of the island, though, could be hosting more than a hundred cats, cementing its status as a flagship protected area. There is direct evidence that all nine of Java’s national parks are still home to the big cats, though no hard numbers for how many live in each park.

“National parks and protected areas provide the most stable and suitable ecological requirements for leopards,” Wibisono said. These parks have the prey, forest cover and human resources required to support leopards, but that doesn’t mean areas beyond park boundaries are uncritical.

In fact, more than half of Java’s potential leopard habitat is outside of protected areas, largely in forests regrowing on farmland and concessions earmarked for logging, according to the paper. Such areas are typically afforded much lower conservation value and security than protected areas, but Wibisono and his colleagues say they believe that engaging the local communities or private companies overseeing these lands could provide vital habitat extensions for leopards, bolstering connectivity between populations.

For instance, Wibisono’s research adds six new priority leopard conservation areas that were missed in previous maps from the Indonesian government and the IUCN. It also identifies seven further high-potential landscapes where future field checks might yet discover the big cats prowling.

Despite being Earth’s most resilient big cats, just as capable of surviving in the arid savannas of Africa as in the urbanized backyards of Mumbai, leopards remain vulnerable to conflicts with humans. More than a quarter of the big cat sightings gathered for Wibisono’s research came from reports of human-carnivore encounters.

“Leopards in anthropogenic landscapes kill livestock, dogs and other animals closely associated with people,” said Erik Meijaard, a long-term researcher and expert in Indonesian wildlife, who was not involved in the study. “But unlike the much larger leopards of Africa and the Asian mainland there are very few records of any lethal conflicts between people and Javan leopards.”

Nevertheless, rural communities are sometimes involved in retaliatory killings, or else request the capture of problem cats by conservation authorities. Between 2009 and 2017, residents of Cikupa village in western Java caught three leopards, handing one over to the local wildlife conservation agency.

“Once in captivity leopards are rarely if ever released because communities are unlikely to support the introduction of this predator in their vicinity,” Meijaard said, noting that “as much as possible such captures need to be avoided.”

Illegal hunting for leopard body parts could also be hurting wild populations. When researchers from Padjadjaran University in West Java and the University of Auckland in New Zealand interviewed residents of Girimukti village in 2016, they discovered that Javan leopard skins sell locally for about $140 to $425. Their bones, crushed and used for traditional medicinal purposes, go for around $18 per kilogram. And their tongues — dried, inserted into wood, and wrapped in Arabic-inscribed cloth — fetch $70 as religious amulets.

“Leopards are very good at surviving in human-dominated landscapes. Conservation efforts should therefore focus on ensuring that no animals are killed or caught, and maintaining healthy prey populations,” Meijaard said.

Despite being declared officially extinct in 2008, the legacy of the Javan tiger still looms large over Wibisono’s study. His team encountered many reports of local people convinced that tigers still roam the island.

“They might have been confused between Javan tigers and Javan leopards,” Wibisono said, adding that some people might be reluctant to accept that the Javan tiger is indeed extinct.

Incidences of confusion between leopards and tigers are not uncommon. In 2017, a photo taken by rangers at Ujung Kulon National Park sparked viral speculation that Java’s tigers could be back from the dead. Closer inspection by scientists revealed the cat to be of the spotted and not the striped variety.

The extinction of the Javan tiger due to many of the same threats faced by its smaller cousin provides a cautionary tale for the Indonesian government. Action, fast and science-based, is required to save the island’s leopard from the tiger’s fate.

References

Wibisono, H. T., Wahyudi, H. A., Wilianto, E., Pinondang, I. M. R., Primajati, M., Liswanto, D., & Linkie, M. (2018). Identifying priority conservation landscapes and actions for the Critically Endangered Javan leopard in Indonesia: Conserving the last large carnivore in Java Island. PloS one, 13(6), e0198369.

Wilting, A., Patel, R., Pfestorf, H., Kern, C., Sultan, K., Ario, A., … & Fickel, J. (2016). Evolutionary history and conservation significance of the Javan leopard Panthera pardus melas. Journal of Zoology, 299(4), 239-250.

Partasasmita, R., Shanida, S. S., Iskandar, J., Megantara, E. N., Husodo, T., Parikesit., & Malone, N. (2016). Human-leopard conflict in Girimukti Village, Sukabumi, Indonesia. Biodiversitas : Journal of biological diversity, 17(2), 783- 790.