The Sumatran rhino has not been seen in the state of Kalimantan, Borneo, for more than two decades, but recent evidence has been found to suggest that this threatened species still occurs in the Indonesian state.
Now considered to be one of the world’s most threatened mammals with just 200 to 275 individuals remaining in the wild, the Critically Endangered Sumatran rhino once roamed across the Himalayan foothills and east to southern China, Myanmar, Thailand, Cambodia, Lao PDR, Viet Nam and Peninsular Malaysia. However, this impressive range has since been dramatically decreased as a result of hunting and habitat destruction.
Also known as the ‘hairy rhino’ due to a covering of reddish-brown to black hair, the Sumatran rhino is known to survive in small populations on Borneo in the Malaysian state of Sabah, but this is the first time that scientists have been able to confirm the presence of this shy and elusive species in the state of Kalimantan for over 20 years.
While conservationists from WWF-Indonesia have yet to spot a rhino in Kalimantan, the discovery of footprints, mud wallows, tree markings and signs of rhino feeding all indicate that at least one Sumatran rhino persists in the area.
“This is a very important finding to the world, and especially to Indonesia’s conservation work, as this serves as a new record on the presence of Sumatran rhinos in East Kalimantan and especially in West Kutai,” said Bambang Noviyanto, the director for biodiversity conservation at the Forestry Ministry.
In such small and fragmented populations, it has become difficult for populations of the Sumatran rhino to breed successfully, and cases have been reported in the past of single rhinos surviving alone in a small forest fragment. The rarer the species becomes, the more challenging it is for scientists to count and monitor the number of remaining individuals.
As yet, there is no information on whether the recent evidence has been left by just one rhino or a small group, but scientists believe it is unlikely that the group is large.
“The Sumatran rhino is on the very brink of extinction. The fact that this discovery comes more than a decade after the last evidence of the species in Kalimantan, despite the opening up of previously remote areas during that period, suggests that this might be just one or a small number of individuals,” explained John Payne, a conservation scientist with the Borneo Rhino Alliance (BORA). “If so, they might not have been breeding. There may be inbreeding, or a skewed sex ratio, or simply old or otherwise infertile rhinos.”
Along with other scientists at BORA, Payne is currently working to breed two Sumatran rhinos in large, semi-wild enclosures in Sabah, Malaysia, one of which was found living alone in a fragment of forest with no hope of finding a mate to breed with.
A similar breeding programme in Sumatra led to the first successful birth of a captive Sumatran rhino since 2001. Given that it was only the fourth captive Sumatran rhino birth in the last century, this was an impressive achievement, but Payne believes that more rhinos will need to be captured to increase genetic diversity within the population and ensure that the breeding programmes are successful in the long term.
“I would hope that consideration might be given to capture to add to the global captive population of 10 individuals,” said Payne. “New genes are needed. Borneo Rhino Alliance (BORA), although a Malaysian NGO, would be happy to collaborate with WWF-Indonesia and the Indonesian authorities. Such collaboration would help in exchanging information and ideas, and help to better secure collaboration on this species between Indonesia and Malaysia.”
At present, WWF-Indonesia is focusing its efforts on determining how many rhinos are currently living in East Kalimantan, and the organisation is working with local communities to ensure that the area is protected.
Read more on this story at Mongabay.com – Sumatran rhino found in Kalimantan after unseen in region for 20 years.
Kathryn Pintus, ARKive Text Author