I have way too many (like too much) sources on sloth bear and tiger so I’ll post a few:
Sloth bears are known for their pugnacity and aggressiveness They can do some serious damage with their long claws. They sometimes bite with their semi-toothed muzzle and hold on like a pit bull. Females are generally accommodating to other females. Fights sometimes break out between males.
Sloth bears have been observed fighting with tigers and holding their own. One ranger told Smithsonian magazine he observed a sloth bear slap a tiger in the face and push it away. The tiger fled after that. The same ranger said he once saw a sloth bear take on three large tigers, each of which fled in a different direction after the encounter. However, tigers do kill sloth bears more often than visa versa. In most cases a tiger can kill a sloth bear of it wants to but is fearful if suffering severe wounds in the process.
redirect.viglink.com/?key=71fe2139a887ad501313cd8cce3053c5&subId=7226874&u=https%3A//factsanddetails.com/asian/cat68/sub433/entry-3574.htmlSloth bears are not the most frequently killed prey by tigers:
redirect.viglink.com/?key=71fe2139a887ad501313cd8cce3053c5&subId=7226874&u=https%3A//photos.app.goo.gl/eeeS2sDNASGq2pUr9Source:
redirect.viglink.com/?key=71fe2139a887ad501313cd8cce3053c5&subId=7226874&u=https%3A//link.springer.com/article/10.1007/s10531-012-0298-y%23Tab2In Chitwan National Park, Nepal, where there are sloth bears, its looks like the tiger predation is 0%
Diet of Bengal Tigers (Panthera tigris tigris) in Chitwan National Park, Nepal
Abstract and Figures
We studied the diet of the Bengal tigers (Panthera tigris tigris) in Chitwan National Park, Nepal, by identifying 109 prey items from 85 tiger scats. Tigers in this region fed upon eight different mammal species. Chital (Axis axis) was the major prey with a frequency of 45% of the Tigers’ diet. The occurrence of other prey species included sambar (Cervus unicolor, 23%), wild pig (Sus scrofa, 15%), hog deer (Axis porcinus, 9%), barking deer (Muntiacus muntjak, 4%), and gaur (Bos gaurus, 2%). Tigers also hunted livestock, but this prey comprised a small component of the relative biomass (buffalo 5% and cow 2%). Our study suggests that the tiger depends mostly upon wild prey for its subsistence in the Chitwan National Park, but will also sporadically hunt livestock.
www.researchgate.net/publication/320263844_Diet_of_Bengal_Tigers_Panthera_tigris_tigris_in_Chitwan_National_Park_Nepal"During a study on tigers in Taman Negara, Peninsular Malaysia, Kawanishi (2002) encountered one Sun Bear carcass presumed killed by tigers and two tiger scats containing the remains of Sun Bear(s), but again the frequency of these interactions is unknown. At the minimum, tigers and leopards are presumed to be antagonistic when encountering Sun Bears (Augeri 2001)".
Sloth bear, Melursus ursinus Shaw, 1 791 (Mammalia Ursidae), from India: conservation issues and management actions, a case study
Abstract and Figures
One of the 12 mega biodiversity centres of the world, India is unique in having four of the eight bear species (Mammalia Ursidae) that are found in the world. They are brown bear (Ursus arctos Linnaeus, 1758 s.l.), Asiatic black bear (Ursus thibetanus Cuvier, 1823), sun bear (Helarctos malayanus Raffles, 1821) and sloth bear (Melursus ursinus Shaw, 1791). The abundance of sloth bear in India, which is also present in Sry Lanka with the endemic sub-species Sri Lankan sloth bear, M. ursinus inornatus Pucheran, 1855, is determined by its location within the global distribution range, quantum, quality and continuity of habitat available and the anthropogenic pressures the species faces. Bears in India are threatened due to poaching for bear parts, retaliatory killings to reduce conflicts and habitat loss due to degradation and fragmentation. In addition to these concerns, the rehabilitation of communities that eke out a living on dancing bears has made bear conservation a challenge in India. Deforestation and hunting are major threats to bears in India. Unless urgent conservation measures are taken and degraded forest areas are restored, we suspect that sloth bear may soon become endangered in India.
Adult males weight 80-140 Kg and females weight 55-95 Kg (Prater, 1980; Garshelis et al., 1999b).
The median for males would be 110 kg (242 lbs). For females 75 kg (165 lbs).
redirect.viglink.com/?key=71fe2139a887ad501313cd8cce3053c5&subId=7226874&u=https%3A//www.researchgate.net/publication/272022633_Sloth_bear_Melursus_ursinus_Shaw_1_791_Mammalia_Ursidae_from_India_conservation_issues_and_management_actions_a_case_study"Tigers occasionally attack and kill Sloth bears as evidenced by one case in Chitawan during our study and accounts recorded in the older literature (Littledale, 1889; Fenton, 1909).."
Note: No details are provided for the Chitawan bear.
Source: Laurie, A., and J. Seidensticker. 1977. Behavioural ecology of the sloth bear (Melursus ursinus). Journal of Zoology, London 182:187-204.
Why are the sloth bears aggressive?
"While sudden encounters in poor visibility habitats may be a proximate factor determining the probability of attacks, the ultimate factor might be the defensive response of sloth bear to humans that manifests as an aggressive disposition. Sloth bears probably evolved within the Indian subcontinent sympatrically with larger predators such as the tiger. The evolutionary pressures of predators may have influenced the development of aggression in sloth bears (Plate 14b). Laurie and Seidensticker (1977) suggested that the aggressive behaviour of sloth bears may be a consequence of not being able to rely on trees for escape, in a habitat that holds tree-climbing predators like the leopard, and also makes it advantageous to live in fairly open habitats. Incidents of sloth bear mortality caused by predators have been reported from several places in its range (reviewed in Joshi et al. 1999). In Panna, sloth bears had several agonistic interactions with tigers and were also occasionally killed by tigers (unpublished data). Sloth bear cubs seldom climb trees to avoid predators. Therefore, offence may be the mother bears best defense strategy and this strategy has been considered to have important survival value for the grizzly bear cubs (Herrero 1970). However, there are also costs associated with attacking humans. Therefore, the bears may be making decisions based on the risks and benefits of attacking (or may have developed it over evolutionary time) and might not be acting arbitrarily, contrary to popular belief.
Aggression may have also developed due to competition among conspecifics over resources. The aggressiveness of the sloth bear is perhaps adaptive in their interactions with conspecifics, predators like tiger, leopard and other sympatric mammals like elephants and rhinos, and the bear may show the same kind of reaction to humans (Laurie and Seidensticker 1977, Herrero 1985, Garshelis et al. 1999). Humans might have been occupying the Indian subcontinent for at least 4000 years and probably have had regular agonistic interactions with the sloth bears. As a consequence, sloth bears may have evolved aggressive reactions towards humans. In the last 200 years or so, human persecution of bears has been more severe (Dunbar-Brander 1926, Rangarajan 1996, 2001) and these interactions might have reinforced the negative perceptions of humans. Sloth bears have been observed to have low tolerance towards people and conflicts with humans are common in most of its range (Garshelis et al. 1999, Yoganand et al. in press)."
"My observations on interactions that sloth bears had with conspecifics, tigers and humans in Panna indicate that there are several responses that are common in these interactions, particularly in the way sloth bears reacted to both tigers and humans. Sloth bears actively avoided tigers and humans when they became aware of their presence in advance. When they heard suspicious sounds made by humans, tigers, or even alarms raised by other animals such as sambar (Cervus unicolor) or common langur (Trachypithecus entellus) to the presence of predators or humans, the bears became vigilant. They paused their activity and waited for further sounds or scents, looked in the direction of the sound, or exhibited such vigilant behaviour. When the bears sensed the presence of adversaries, they stopped their activity, moved in a different direction or even took shelter under secure cover. Sometimes, they did not emerge out of dens until long after their usual times of start of activity. Occasionally they also fled on sensing a threat, or at other times, they rushed towards the tiger or the human. Similar reactions were also observed in Chitwan NP, Nepal. At close quarters, sloth bears reacted to humans and tigers similarly, often by roaring and running away, or roaring and attacking before retreating (Laurie and Seidensticker 1977). These observations indicate that the bears perhaps perceived humans as predators or equivalent to predators. However, a peculiar behaviour that I observed that may confound other observed patterns to a considerable extent is that the bears while foraging, were often quite preoccupied and did not pay attention to things other than searching for food, unless there was sound or scent coming by its way. Several times, when I was still and silent the bears approached me (mostly when in a jeep or treetop, but sometimes even when on foot) without noticing me, coming as close as a distance of 10 m, usually after which I made noise and scared it away."
Does the activity of tigers, humans, and adult male bears influence bear
activity?
"Tiger activity does not seem to influence bear activity timings. The hourly activities of both species (in dry and cold seasons) were strongly positively correlated, even after controlling for the effect of temperature. They both were mainly crepuscular and nocturnal in activity and were probably influenced by the same thermal factors or an endogenous rhythm. Tigers showed a more bimodal pattern of activity than sloth bears, which was because of more daytime activity and much less post-midnight activity. This kind of increased day activity could be caused by the more thermal-buffered microhabitats (shaded, riverine habitats, etc.) the tigers used, and by the different foraging behaviours and underlying physiologies of both species. I did not find any evidence to support the hypothesis that bears avoid encountering tigers (reduce predation risk) by choosing a different timing to be active. Joshi et al. (1999) believed that to have happened in Chitwan NP, Nepal, but did not present evidence to support it. American black bears are reported to avoid brown bears by being active at a different period (Aune 1994). Many prey species are known to avoid predation risk by temporal and spatial segregation from the predators (Clarke 1983, Caldwell 1986, Ferguson et al. 1988, Lima 1988, Lima and Dill 1990)."
"Tiger avoidance may not be a primary force in shaping the diel activity of sloth bear, because they do not seem to have a strictly prey-predator association. Tigers do prey on sloth bear (Laurie and Seidensticker 1977, Joshi et al. 1999, unpublished data), but the killings may happen primarily during close encounters between them, and not as a case of hunting. Sloth bears are aggressive, strong, with sharp claws and large canine teeth and they could inflict serious injuries on tigers. There have been instances when tigers have been injured or chased away by sloth bears or both withdrew during such close encounters (Joshi et al. 1999, personal observations). So, the tigers too may perceive a risk and therefore avoid encountering bears. For the bears, tigers may just be adversaries, with the outcome risky mainly when encountered suddenly. Therefore, it may not be critical for sloth bears to avoid the timings when tigers are active. Sloth bears in Panna NP did not seem to avoid tigers spatially either. They frequently use habitats such as escarpments (see Chapter 6: Space Use and Habitat Selection) that tigers also frequently used. Escarpment habitat offers suitable daytime resting sites for both species and they use this habitat frequently and simultaneously. However, it is possible that the bears may be avoiding certain microhabitats that tigers frequently use, or actively avoid tigers by avoiding places where they are present. I have found evidences of active avoidance of tigers by sloth bears and relatively frequent vigilance behaviour in bears (personal observations) in Panna NP."
I will also debunk some arguments from tiger enthusiasts in the coming days.