Yovanda, Mongabay | July 1, 2020
SAMARINDA, INDONESIA: The search for a potential mate for a captive female Sumatran rhinoceros in Indonesian Borneo has been put on hold for the year, one of many activities frozen by the COVID-19 pandemic.
Conservation experts and authorities around the world agree that breeding Sumatran rhinos (Dicerorhinus sumatrensis) in captivity is the best bet to save the critically endangered species, which numbers fewer than 80 individuals in the wild. The government of Indonesia, the last country where the species is found, has called for the capture and translocation of wild rhinos from critical subpopulations in Sumatra and Borneo to local sanctuaries for the breeding initiative.
But the coronavirus pandemic has prompted officials in the Bornean province of East Kalimantan, where a population of wild rhinos is believed to survive, to halt their capture efforts this year.
“Right now amid the pandemic, the focus on protection is increased,” said Jono Diputro, an official at the provincial government’s conservation agency. “After the coronavirus has passed, we will resume it.”
In 2018, conservationists captured a wild female rhino in East Kalimantan and moved her to the newly built Kelian Lestari sanctuary. The rhino, named Pahu, is the first of her species from Borneo to be placed in the breeding program. Another sanctuary, at Way Kambas National Park in Sumatra, hosts seven rhinos as part of the program.
While Pahu is believed to be healthy and showing no signs of reproductive problems, her isolation at Kelian Lestari could be problematic. Previous research indicates that female Sumatran rhinos do not ovulate naturally when males are not present.
Officials estimate there are fewer than 16 rhinos left in eastern Borneo, and have regularly monitored three individuals. Their plan is to find and capture a male that can join Pahu for the captive-breeding effort.
But the COVID-19 crisis has put a halt to field work, among other activities. Officials say the search for a wild rhino has also been hampered by locals who refuse to allow any rhinos captured in their areas moved to the Kelian Lestari sanctuary. They have demanded authorities build another facility in the area where the rhino is found and captured.
The East Kalimantan government has called on residents to support the program for the sake of the species.
Without a male in sight to join Pahu, the environment ministry says it will attempt to fertilize eggs harvested from Pahu with sperm obtained from one of the captive males at Way Kambas. While the main goal is to produce a newborn calf, this effort could also boost the gene pool of the species; with so few individuals left in the world, inbreeding is a major risk. The rhino populations in Sumatra, D. s. sumatrensis, and Borneo, D. s. harrissoni, are subspecies that have been genetically separated for hundreds of thousands of years.
The species has been driven to the edge of extinction by habitat loss, with Sumatra and Borneo losing vast swaths of forest to oil palm plantations and coal mines, as well as poaching. Now, with a dwindling number of rhinos scattered in fragmented pockets of forest, conservationists cite a low birth rate as the primary threat to Sumatran rhinos’ survival.