The endangered great one-horned rhinoceros have continued to die throughout the year, making the last fiscal year 2018-19 one of the worst years for pachyderms in the country.

A total of 46 one-horned rhinos died last year in and around the Chitwan National Park, recording the highest mortality of rhinos for the park in a year due to natural causes.

The fatality rate looks daunting, especially at a time when these deaths have been attributed to natural deaths with the authorities maintaining a complete control over illegal poaching. In the last five years, only one rhino has been poached.

Now, these rhinos are succumbing to injuries during territorial clashes and old age, drowning, labour pain during births, infections and other diseases.

Last year, eight rhinos died due to old age, seven were killed in territorial fights, two succumbed to infection and one each were killed in an attack by tiger, crocodile, falling into septic tank pit and after being electrocuted, among other known reasons.

The alarming rise in rhino deaths, especially due to natural factors, worries government officials.

“If we look at the total number of rhinos inside the Chitwan National Park, the death ratio might look normal. However, the sudden rise in the number of deaths due to natural factors cannot be usual,” Bishnu Prasad Shrestha, spokesperson for the Department of National Parks and Wildlife Conservation, told the Post.

Over two decades since the park started keeping track of the number of rhino deaths, only twice has the number of rhino deaths surpassed last year’s fatality rate—due to combined poaching and natural causes.

Forty-eight rhinos had died each in 2001-2002 and 2002-2003. But those deaths were attributed to poaching. A total of 37 rhinos were killed by poachers in FY 2001-2002, followed by 32 next year.

Never before in the park’s recorded history more than 28 rhinos were reported dead, which was recorded in fiscal year 1999-2000, due to natural causes—one of the only two categories maintained by park while maintaining figures on rhino deaths. A large number of rhinos had died because of natural factors at this rate when the country continues to celebrate zero poaching years.

The unprecedented upsurge in death of rhinos due to natural causes was witnessed in the last three years. In the fiscal year 2016-17, 25 rhinos were reported dead, including one killed by poachers—the first instance of poaching in the last five years. A total of 26 rhinos died inside the park in 2017-18.

Before such a terrifying increase, which was observed since mid-2017, the number of deaths due to natural causes would be around 15 annually, according to the department records.

Officials at the department said the sudden rise in natural death of rhinos inside the protected area could be linked to the Tarai flood of 2017 when many wild animals, including rhinos of the parks were killed. A number of rhinos were even swept down to India.

“When we witnessed an increase in such deaths, we beefed up monitoring of the rhino habitat. We scanned the whole potential habitat of rhinos and we found many carcases of rhinos, which might have died during the floods,” added Shrestha.

After shrinking of habitat which was attributed to fighting between rhinos over territory, which at times would result in their deaths, the park has also started working towards habitat management by improving grassland for rhinos and building and upgrading ponds inside the park.

Likewise, as causes of most of the deaths were unknown, the park authority had also tested samples from water resources inside the park and body parts of dead rhinos.

“We thought water pollution could be a cause of such unknown deaths. But nothing was found during the water sample tests,” said Shrestha. “Also, there were no serious diseases or infections when the body parts were examined in labs in Kathmandu.”

In the last 21 years, a total of 479 one-horned rhinos have died inside the Chitwan National Park due to various reasons. Rhino conservation was met with a new challenge during the decade-long armed conflict when there was rampant poaching.

While death of rhinos are on all time high, the government has said that it would be conducting the rhino census this year.

In its bid to find out the reason for these deaths, the department has also started a study to the carrying capacity of Chitwan National Park. It hosts 605 rhinos concentrated in an area of 932 square kilometres as per the last census of 2015.

“The department has formed a team of experts to study the carrying capacity of the park. The findings of the study will hopefully explain everything,” said Bed Kumar Dhakal, chief conservation officer of the park.