Nepal has had remarkable success at tackling the poaching of its greater one-horned rhinos but, since 2015, it has witnessed a sharp increase in deaths from unknown or natural causes.
Thousands of tourists from around the world flock to Nepal’s Chitwan National Park every year to get a glimpse of the greater one-horned rhinoceros. But for 46-year-old Nabin Adhikari, the animals are like colleagues. A wildlife guide for 16 years, Adhikari knows these rare animals and their habitat up close.
“Just a few months ago, I saw two rhinos fight for two to three hours,” he says at the beginning of an early morning tour. “Eventually, the brawl ended and one of the rhinos was dead.”
Adhikari says he reported the incident to the park’s veterinary staff.
The rhino whose death Adhikari witnessed was one of at least half a dozen to die of non-human-related causes in the park in the first nine months of 2018. And its death appears to represent a growing trend in the park. Between 2004 and 2014, a total of 81 rhinos died from unknown or natural causes—an average of around seven per year. That number has since shot up: From 2015 to 2017, 60 such deaths were recorded, an average of 20 per year.
“Whenever we get a call reporting a death, we have a feeling that it must be a greater one-horned rhino,” says one park staffer.
Nepali conservation authorities, who have been lauded for winning the war against poaching and shoring up the country’s rhino population to unprecedented numbers, are now worried that threats to the species persist. Now it’s these “unexplained” or “natural deaths” that are raising alarm. The spike in such deaths since 2014 is being taken seriously by the Department of National Parks and Wildlife Conservation, which recently formed a committee to prepare a report on the issue.
The results of the government study into rhino deaths have not yet been released. In the meantime, people on the ground advance a number of theories.
Guides like Adhikari keep a keen eye on the rhinos—their livelihood depends on knowing where tourists are most likely to spot the animals they pay to come and see. “For me, the reason rhinos are dying is that they are fighting among themselves more often,” Adhikari says. “But if you want to understand the rhinos, you need to look at the Rapti.”
Snaking from east to west along Chitwan’s northern border, the Rapti River is a lifeline for the rhinos, which spend much of their lives immersed in water or grazing on aquatic plants. Driving through the Kumroj Community Forest buffer zone in the park’s east, Adhikari gestures into the distance. “Those are the waterholes where we’d see rhinos wallow for up to 16 hours in summer,” he says. “But now, you neither see the waterholes, nor the rhinos.”
Adhikari’s observations are backed by science: The river is changing. Mammologist Shant Raj Jnawali points to a number of factors: increasing human settlement in the headwaters of the river has led to land degradation and more silt in the water. This sediment has reshaped the riverbed and buried waterholes previously used by rhinos. The construction of dikes along the eastern part of the park has also altered the river’s flow.
Rhinos are feeling the impact. Last year’s monsoon flood caused unprecedented property loss and animal casualties. The river inundated the eastern part of the park and at least 15 rhinos were swept away to India. One was found dead in the western sector. Many more were injured.
“That was the effect of the flood that was visible immediately. But there are other things that were not so obvious,” says Ram Kumar Aryal, head of the Biodiversity Conservation Centre at Nepal’s National Trust for Nature Conservation. Aryal, who has been involved in Nepal’s rhino conservation program since its inception, says the flood may have pushed the rhino population downstream, into the park’s western sector.
Rhinos also likely moved west in search of new watering holes after theirs were silted up, Jnawali says.