An important part of caring for animals in captivity is ensuring they live in the correct, natural social structure – but is equally important to look at a social structure that works for the species in a specific situation. Tigers are generally solitary animals with the exception of tigresses and their cubs and do not typically form family groups or packs like other large carnivores do [1]. However, this solitary nature should not be confused with being antisocial. In fact, tigers can be very social with other tigers especially as male territories overlap the females.
Tigers have also been seen together in larger groups with sisters raising cubs together and even been seen in larger numbers sharing a kill with dominant males allowing cubs to eat alongside peacefully. Often these tigers are related to each other or have previously mated. There have even been a few documented instances of tigers collaborating in a hunt. It’s possible that while tigers are solitary in the wild, this is only out of necessity due to competition for resources.
Conspecifics
Currently, research into whether tigers enjoy the companionship of other tigers shows the topic is up for debate. For example, studies have shown that tigers paired up at night had decreased pacing behaviour when compared to tigers housed alone [2] or showed more chuffing (positive greeting by tigers) when housed socially at night [3] indicating they enjoyed these interactions and possible benefit from being housed in pairs. Another study has shown that tigers paced more when they could see or have sensory interactions with other tigers but not reach them. Putting up a visual blockade reduced the amount of pacing these tigers performed [1,4] but in yet another study [5], pacing increased with the visual blockade possibly indicating tigers behave negatively when unable to control their exposure to visual or olfactory stimuli [6]. It’s unclear whether this increased activity was negative or positive – the tigers could have been active due to aggression or simply in their frustrated desire to interact in a positive way with the other tiger [6].
There is also the possibility of sex playing a part, with a male tiger pacing more when able to see female tigers in an adjacent enclosure [3] or simply a more aggressive, dominant male seeing another male. The personality of the tiger and previous experiences should also be factored in when considering the ability to see conspecifics [6]. Evidence does suggest that tigers kept in captivity are more social than their wild tiger counterparts, though it’s possible that personality is also key to these differences.
When keeping tigers together it’s very important to ensure that they get along, monitoring their behaviour toward one another. Social groupings can be beneficial, but not always. However, a recent study showed that tigers did tend to form small, social groups with preferred individuals and that group hosing is potentially tolerated in certain situations [7]. Factors such as age (younger tigers generally appear to enjoy the company of other tigers as they grow up), sex (females seem more likely to get along later in life though brothers or males raised together are also able to co-exist happily) and personality (like humans, some tigers just don’t enjoy other tigers being around), all impact social groupings.
Tigers can also show different behaviours in response to stress so it’s important for keepers to understand these behaviours to make changes accordingly. The context of the behaviour being performed should also be taken into account when viewing neighbours, and also what the neighbouring tigers are doing. To throw an extra element in the mix, what might be preferred by one tiger, might not be what another tiger enjoys particularly when it comes to male and female tigers and their differing reproductive drives. Increased activity due to a visual barrier preventing monitoring of a neighbour will need a different approach to a tiger pacing from social learning [6].
Other animals/prey animals
Another option for captive tigers is the ability to see other species. These species will not be kept within the enclosure as captive tigers are likely to want to hunt and chase them. Prey species can also suffer a huge amount of stress when being hunted by a predator – and it’s illegal in a number of countries, due to poor welfare. It’s also possible that the predator can get injured in such a hunt, as the prey fights back.
Some zoos will choose to put natural prey in the eye-line of the predator when in captivity. This can help to stimulate the tiger’s natural hunting instinct, but at the same time, the tiger cannot follow through with performing the hunt which can lead to frustrated behaviours and stereotypies occurring. It’s therefore important to carefully consider whether providing an eye-line to a prey species is actually beneficial to the tiger at all. And let’s not forget that the prey species could suffer from increased levels of stress due to the vicinity of the tiger as well.
References
1). Szokalski, M.S., Litchfield, C.A. and Foster, W.K. (2012). Enrichment for captive tigers (Panthera tigris); Current knowledge and future directions. Applied Animal Behaviour Science 139(1-2): 1-9
2). De Rouck, M., Kitchener, A.C., Law, G. and Nelissen, M. (2005). A comparative study of the influence of social housing conditions on the behaviour of captive tigers (Panthera tigris) Animal Welfare 14, pp. 229–238
3). Miller A, Leighty KA and Bettinger TL 2013 Behavioral Analysis of Tiger Night Housing
Practices. Zoo Biology 32: 189-194
4). Miller, L.J., Bettinger, T. and Mellen, J. (2008). The reduction of stereotypic pacing in tigers (Panthera tigris) by obstructing the view of neighbouring individuals. Animal Welfare 17(3), pp. 255-258
5). Bashaw, M.J., Kelling, A.S., Bloomsmith, M.A. and Maple, T.L. (2007). Environmental effects on the behaviour of zoo-housed lions and tigers, with a case study of the effects of a visual barrier on pacing. Applied Animal Welfare Science. 10(2), pp. 95-109 doi: 10.1080/10888700701313116.
6). Whitham, J.C. and Miller, L.J. (2019). A Zoo Animal’s Neighbourhood: How Conspecific Neighbours Impact Welfare. Animal Welfare. 28(2), pp. 127-136 doi: https://doi.org/10.7120/09627286.28.2.127
7). Galardi, E.G.Fabbroni, M., Rausa, F.A., Preziosi, R., Brereton, J.E., Pastorino, G.Q. (2021). An Investigation into the Behavior, Sociality and Enclosure Use of Group-Housed Lions and Tigers. Journal of Veterinary Medical and Animal Sciences. 4(1): 1068