Big cat and Bear tale

[Diamir2]

"Sloth bears seldom feed on carrion (a highenergy resource and a possible source of protein), probably because of the risk of predation by sympatric predators, tiger and leopard, which generally guard their kills (Laurie and Seidensticker 1977). There could also be competition for carcasses from efficient scavengers such as the striped hyaena and wild pig."
"Tigers attack and kill sloth bears occasionally (Joshi et al.1999, personal observations), however encounters between them are fairly common (unpublished data).
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 In Panna, sloth bears had several agonistic interactions with tigers and were also occasionally killed by tigers (unpublished data).Tigers attack and kill sloth bears only occasionally (Laurie and Seidensticker 1977, Joshi et al. 1999 and the references therein), however encounters between them are fairly common (unpublished data).
Tiger avoidance may not be a primary force in shaping the diel activityof 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a strictly prey-predator association.Tigers do prey on sloth bear (Laurie and Seidensticker 1977,Joshi et al. 1999, unpublished data), but the killings may happen primarily during close encounters between them, and not as a case of hunting.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 mainlywhen 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 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.
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)"                                                               K.Yoganand, 2005, “Behavioural Ecology of Sloth Bear (Melursus ursinus) In Panna National Park, Central India”, thesis PhD, Saurashtra University
"We never observed Sloth bears eating carrion or preying on other mammals. McDougal (pers. comm.) who conducted an extensive tiger baiting programme in Western Chitawan reported only one instance of a Sloth bear feeding from a buffalo killed by a tiger. Sanderson (1890) reported that occasionally Sloth bears scavenged tiger kills and gnawed on cattle bones"                                         A. Laurie,J. Seidensticker 1976 "Behavioural ecology of the Sloth bear (Melursus ursinus)"

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