Leading the charge: wildlife experts plan for future of Nepal’s rhinos

© Provided by The Guardian Photograph: Sergi Reboredo/Alamy

© Provided by The Guardian Greater one-horned rhinos at Chitwan national park. More than 100 of the species died of natural or unknown causes between 2016 and 2020. Photograph: Hemis/AlamyBut the greater one-horned rhino is still classified as vulnerable by the International Union for Conservation of Nature (IUCN), and a new threat has emerged.

While there were only about five confirmed deaths due to poaching between 2016 and 2020, more than 100 rhinos were reported to have died of natural or unknown causes. “Poaching used to be the reason for rhino mortality. But in recent years, the government has done an excellent job in protecting rhinoceroses from poaching,” says Pant, a conservation officer working for the Department of National Parks and Wildlife Conservation in Nepal.

“At this point, we cannot say that [these deaths are] only due to the impacts of climate change,” says Pant, who is studying for a PhD with the University of Southern Queensland, Australia. But he believes that the climate crisis could be one of the underlying causes. Pant and a team of researchers developed a set of 21 indicators to assess the vulnerability of the rhinos in Nepal to climate change.

They concluded that they were “moderately vulnerable” to the impacts of global warming, primarily due to the likelihood of invasive species and extreme flooding in prime rhino habitat, along with habitat fragmentation, droughts and forest fires.

“I’ve tried to look at the likely shift in the habitat of the rhinoceros in Nepal in the next 50 years in different climate change scenarios,” he says. “And to find out what would be the adaptation measures – to enhance the resilience of the rhinoceros in the context of likely impacts of climate change.”

© Provided by The Guardian A one-horned rhinoceros grazing at Chitwan. They require enough flooding to maintain their grassland habitat. Photograph: imageBroker/AlamyRhinos are a highly adaptive species, hence their categorisation as moderately vulnerable. “That means it’s not at risk of immediate extinction due to climate change, but we have to consider it at the moment if we are to sustain the population for the long run,” says Pant.

Wendy Foden, a conservation biologist, agrees: “We are currently experiencing the fastest rate of climatic change in 65m years. If conservation planning efforts are to remain relevant and strategic, they must include the best available science on anticipated future impacts.”

Recent studies have shown several species of animals are already feeling the impact and are responding by shifting their habitats and even growing appendages or larger beaks, legs and ears to better regulate their body temperature in some cases. However, predicting the effects of the climate crisis on biodiversity is a challenge, in part because of the lack of long-term observational data.

“It would be very unwise to plan species conservation actions before thoroughly assessing what can go wrong for that species, the mechanisms of potential impacts, how sensitive it is to these, and whether it is likely to be able to adapt of its own accord,” says Foden, who chairs the IUCN Species Survival Commission’s climate change specialist group, and led the development of IUCN guidelines for assessing species vulnerability to climate change.

“These provide the foundations from which to build solid conservation plans. So in most cases, climate change vulnerability analysis is imperative for species conservation planning.”

© Provided by The Guardian A greater one-horned rhino in Janakauli community forest, a buffer zone bordering Chitwan. Working more closely with the local community, as well as increased security, has helped rescue Nepal’s rhinos from poachers. Photograph: Gemunu Amarasinghe/APPant’s research looked at the one-horned rhino’s climate crisis vulnerability according to sensitivity, exposure and adaptive capacity. Sensitivity is how strongly a species is likely to be affected by climate change; exposure is the extent to which their physical environment will change; and adaptive capacity is their ability to overcome the negative impacts of climate change.

While the one-horned rhinos fared well in the climate change vulnerability analysis, the changing climate is already threatening the rhino population in Chitwan national park. The species is dependent on a certain level of annual flooding to maintain its habitat.

But over the last few years, extreme flooding has affected the park several times, sweeping rhinos downstream into India and bringing debris and rubbish from upstream.

Drought is also occurring more often, leading to fewer of the ponds that rhinos wallow in to regulate their temperature. Invasive species such as the bitter vine (Mikania micrantha), and Chromolaena odorata, a flowering shrub also known as Siam weed, are spreading at an alarming pace, encroaching into the grasslands that are the rhinos’ prime habitat. Global heating is expected to exacerbate extreme flooding and prolonged droughts, as well as the rapid growth of invasive species in the future.

© Provided by The Guardian More frequent and longer droughts are likely as climate change intensifies. This will cause problems for rhinos, which need ponds to wallow in to help regulate their temperature. Photograph: Galyna Andrushko/AlamyAccording to Naresh Subedi, conservation programme manager at Nepal’s National Trust for Nature Conservation, better population and habitat management are crucial in the fight against the climate crisis. “Currently, our rhino population increment rate is 5%, for example. If we maintain 8% rhino population increment annually, then even if we lose 3% of the rhino population by the annual flood or climate-induced incident, they still will be in a good position.”

Pant agrees, noting that while floods are only seasonal, maintaining a suitable habitat all year is vital to sustain a healthy population. Another recent study by his team found that more than a third of rhinoceros habitat in Nepal could become unsuitable within 50 years due to mostly to climactic changes, but also land use changes.

Pant has proposed seven adaptation measures to secure the one-horned rhino’s future that include: maintaining the ponds rhinos need for wallowing; managing the impacts of floods; creating “refugia”; and actively managing habitats to provide a mosaic of grasslands and wetlands.

“We are talking about adaptation because mitigation might take a long time and also depends on several factors,” says Pant. “It’s not under our control, so the only thing we can do is safeguard the rhinoceros under these extreme conditions. That’s our priority at the moment.”

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Leading the charge: wildlife experts plan for future of Nepal’s rhinos (msn.com)