- A study of sloth bear dens in eastern Gujarat’s dry forests shows that natural caves and rocky hillocks serve as critical resting and cub-rearing sites.
- Bears tend to den on steeper slopes and farther from villages, suggesting they select sites that reduce disturbance and human contact.
- The study notes that rocky hillocks and natural caves can function as important refuges for sloth bears even outside protected areas.
In the dry forests of eastern Gujarat, sloth bears disappear into the landscape every day. Naturally occurring caves on rocky hillocks provide hidden shelters that offer shade, safety and, for some, a place to raise cubs. A recent study takes a closer look at these refuges to understand how sloth bears choose these sites, and why certain aspects of the landscape matter more than others.
“Denning behaviour is a really important part of sloth bear ecology, but surprisingly it has not been studied as much as other aspects like diet or habitat use. Like other bears, sloth bears depend on dens as safe places for resting and for raising their cubs. These sites also provide protection from environmental stress, disturbance and potential threats, especially when cubs are very young,” says Ashish Kumar Jangid, principal project associate at Wildlife Institute of India, and a sloth bear expert.
Finding sloth bears dens
The study was conducted between May 2022 and November 2023 in forests connecting Ratanmahal Wildlife Sanctuary and Jambughoda Wildlife Sanctuary in Gujarat. The landscape stretches across Dahod, Chhota Udepur and Panchmahal districts and covers roughly 324 square kilometres. The terrain is rugged and hilly. Rocky outcrops rise through dry deciduous forest dominated by teak, crocodile bark, mahua, tendu and dhak trees.
Although the sanctuaries themselves are protected areas, the corridor linking them is a mosaic of forest and human use. Sloth bears move through this landscape alongside species such as leopards, rusty-spotted cats, Indian giant flying squirrels, striped hyenas, golden jackals, four-horned antelope and Indian crested porcupines.
Understanding where bears find shelter in such mixed landscapes is important for conservation. But locating their dens and observing them in the wild is far from straightforward. “Sloth bears usually live in rugged terrain with rocky hillocks and dense scrub vegetation. They are also among the bear species most frequently involved in conflict with humans, especially females with cubs, which makes direct observation difficult and sometimes risky,” says Jangid.
To find dens, researchers interviewed 35 forest staff. Among them, two foresters, four forest guards and 15 forest watchers helped locate 62 active or recently used sloth bear dens. Once a potential den site was located, the team searched within a 20-metre radius for signs of bear activity. These included pugmarks, claw marks on rocks, scats, digging signs and disturbed termite mounds.
Infrared-triggered camera traps were placed at 10 dens, each operating for at least 10 trap nights, to confirm whether bears were actually using them. These fell into two categories: 41 resting dens, used by bears during the day, and 21 maternal dens, used by females giving birth or raising cubs. Almost all of the dens were natural caves formed within rocky hillocks, rather than excavated shelters.
Researchers then analysed each den’s surroundings, measuring elevation, slope, vegetation and distance from villages, to understand which features influenced where bears chose to den.
Bear preferences
The results revealed clear preferences. Sloth bears tended to select dens located on steeper slopes, areas that are harder for people and livestock to access. These locations likely offer greater security and reduced disturbance.
Distance from human settlements also mattered. Dens were more likely to occur farther from villages, suggesting these bears favour quieter areas when choosing resting sites.
Maternal dens showed even stronger patterns. These dens were generally located at higher elevations, averaging 219.2 metres, compared with 195.7 metres for resting dens. They were also structurally more complex. Most maternal dens had multiple openings or chambers, which may allow females to watch for danger or escape quickly if needed. On the other hand, most resting dens had single openings.
Some caves were not used exclusively by sloth bears. Researchers also recorded signs of leopards, Indian foxes, striped hyena and Indian mongoose around some dens. “Secure natural caves and boulder cavities may be limited in these landscapes, so several species depend on the same structures. These caves are also shared by other mammals, including leopards, jungle cats and porcupines,” says Nishith Dharaiya, director at the Center of Excellence for Wildlife and Conservation Studies, an independent expert associated with the study.
In many cases, different animals may use these shelters at different times. “The pattern suggests temporal niche partitioning, where different species occupy these sites at different times rather than simultaneously,” he adds. In rugged landscapes where caves are limited, such dens may become valuable resources for several species.
Why dens matter
Unlike many other bear species, sloth bears do not hibernate. They remain active throughout the year. Dens therefore serve mainly as daytime resting shelters and birthing sites.
In most parts of India, sloth bears usually use natural structures such as caves, rock crevices and boulder formations as dens. “Resting dens are often used only for a short time, maybe a day or two. Maternal dens are used for longer periods when the cubs are small,” says Jangid.
For female sloth bears, these shelters are especially important. Cubs are born extremely vulnerable and depend entirely on their mothers. Observations from captive bears suggest that females may remain inside dens for up to 28 days without food or water after giving birth. During this time, the den provides protection from predators, harsh weather and disturbance.
Small features, big importance
The study highlights how rocky hillocks and natural caves can shape where sloth bears live and reproduce. Such features are often overlooked in conservation planning, which usually focuses on forest cover at much larger scales.
The findings suggest that smaller landscape elements, such as steep slopes, rocky outcrops and caves, may be crucial for bear populations. “These rocky hillocks and natural caves can function as important refuges for sloth bears even outside protected areas. It shows that suitable microhabitats may be more important for denning than the formal protection status of the landscape,” says Dharaiya.
This is particularly important in human-dominated landscapes, where wildlife corridors link protected areas but also intersect with farms, villages and roads. Protecting these microhabitats could help maintain safe refuges for sloth bears in landscapes shared with people.
Banner image: A sloth bear mother and cub. Caves on rocky hillocks provide hidden shelters that offer shade, safety and a place for mothers to raise cubs. Image by L. Shyamal via Wikimedia Commons (CC BY-SA 3.0).
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