New brown bear ‘stronghold’ in Nepal redraws species’ range map

KATHMANDU – Researchers have discovered brown bears in a part of Nepal where the species was previously unknown, prompting them to protect the area as a bear stronghold.

The discovery, based on camera trap images, also expands the known range of the brown bear (Ursus Arktos) in Asia. It could also mark the Limi Valley in northwestern Nepal as a “contact zone” between two subspecies of this apex predator, the researchers write in the paper. recently published study.

“Bears were not a species for which we set up camera traps in the first place,” study lead author Naresh Kusi of the Himalayan Wolves Project told Mongabay.

As part of his research, Cusi and his project team have been operating a network of 61 camera traps since 2021 across the Leamy Valley, an area half the size of London. Since then they recorded images of species never previously confirmed outside of Nepal’s protected areas, such as the steppe ferret (Mustela Eversmania), manul (Otocolobus manul) and Eurasian lynx (Lynx lynx).

This time it’s a brown bear, a species found throughout the Northern Hemisphere but so vanishingly rare in Nepal (about 20 individuals) that it is considered critically endangered here. However, Cusi’s team was able to capture dozens of independent images of brown bears from their camera traps.

“Although we have not estimated population size in the Leamy Valley, based on our study and other studies of brown bears, we can say that their numbers currently appear to be underestimated,” Cusi said.

They took more images in their 2022-23 survey than in 2021, likely due to the season, he added.

“In 2021, we were there during the summer season. But the next year we went there in the spring,” Kusi said, adding that brown bears are known to be more active in the spring, when the snow has not yet completely melted and people do not often visit the grasslands.

Researchers say the find is significant because it comes from a region located between the known ranges of two subspecies of brown bear: the Himalayan brown bear (U. a. isabellinus), found further west in India and Pakistan, and the Tibetan brown bear (U. a. itchy), found further north and east as far as Tibet.

“This suggests that this area may be a ‘contact zone’ between the two subspecies,” Cusi said.

In their study, the researchers write that this discovery points to “the importance of the Limi Valley as a stronghold for brown bears in Nepal and highlights the importance of formally protecting currently unprotected wildlife habitats in the Limi Valley.”

They add that the photographed bears appeared to have the physical characteristics of a Tibetan brown bear, including a white “collar” (also called a yellow “scarf” by some researchers) around the neck and black ears. But genetic analysis will be needed to confirm which subspecies they belong to – or whether they are a hybrid of the Tibetan and Himalayan subspecies, if indeed the “contact zone” hypothesis is correct.

Rajan Paudel, co-author recent study about potential habitats for bears in a changing climate in Nepal, agreed that more research into this hypothesis is needed.

“Another interesting aspect to study is whether there are any barriers in and around the Limi Valley that could isolate the brown bear populations to the east (Tibetan) and west (Himalayan) valleys, leading to the development of two separate subspecies:” he added.

While Kusi and his team say their discovery expands the known range of brown bears in Nepal, Paudel and his team’s research suggests that the animals’ overall range is likely to shrink under warming conditions. Their study found that if average global temperatures rise by 2.7° Celsius (4.9° Fahrenheit) by the end of the century, brown bears in Nepal would lose more than two-thirds of their current suitable habitat by 2050. and 82% by 2070.

“Our study also shows the importance of saving brown bears in Limi,” Paudel said, echoing Kusi’s team’s call to protect the area. “If we can do this, we could potentially save both the Himalayan and Tibetan brown bears.”

The presence of brown bears in Nepal is as mythical as the beliefs surrounding them. Until recently, the Tibetan subspecies had never been recorded in the country. (Again, this was a camera trap shoot, confirmed their presence in 2022.) Bears are also considered a possible source of the enduring Yeti myth.

Their presence in the Leamy Valley adds to the wealth of wildlife still found in the area. The valley is located in the trans-Himalayan region, only a small part of which is in Nepal, a country mostly located south of the Himalayas. Exploring the flora and fauna of Nepal’s trans-Himalayan region, home to iconic species such as snow leopards (Panther uncia) and wild yaks (Bos mutus), was limited compared to the lower hills and plains where more famous species such as the great one-horned rhinoceroses (Rhinoceros unicorn) and Bengal tigers (Panther tiger) found.

Abhaya Raj Joshi Mongabay magazine staff correspondent for Nepal. Find him on 𝕏 @arj272.

Banner image: A captive Tibetan brown bear with a signature yellowish “collar” around its neck, similar to a scarf. Image by: Aardwolf6886 via Flickr (CC BY-ND 2.0).

Quotes:

Kusi, N., Gurung, S., Lama, D. T., Pathak, S., Pant, G., Timalsina, K., & Werhan, G. (2024). A New Look at the Geographical Distribution of Brown Bears Ursus Arktos in Nepal. Oryx1-5. doi:10.1017/S0030605324000796

Baral, R., Adhikari, B., Paudel, R. P., Kadaria, R., Subedi, N., Dhakal, B. K., … Tsubota, T. (2024). Predicting potential bear habitat under a changing climate in Nepal. Environmental monitoring and assessment, 196(11). doi:10.1007/s10661-024-13253-2

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It’s not a yeti, but the presence of the Tibetan brown bear in Nepal is no longer a myth