Prevalence and determinants of stereotypic behaviours and physiological stress among tigers and leopards in Indian zoos

Abstract

India’s charismatic wildlife species are facing immense pressure from anthropogenic-induced environmental perturbations. Zoos play a major role in the conservation of threatened species, but their adaptation in captivity is posing a major challenge globally. Stress from inadequate adaptation could lead to suppression of cognitive functioning and increased display of stereotypic behaviour. It is thus necessary to measure biological traits like behaviour, stress physiology, and contextual factors driving the animals maintained at zoos. In this study, we assessed stereotypic behaviour and stress physiology employing standard behaviour scoring, non-invasive stress monitoring, and their contextual drivers in a sub-population of two large felid species managed in six Indian zoos. The prevalence and intensity of stereotypic behaviours and levels of faecal corticosterone metabolites (FCM) were ascertained among 41 Royal Bengal tigers Panthera tigris tigris and 21 Indian leopards Panthera pardus fusca between April 2014 and March 2015. Behavioural observations showed that tigers spent more time stereotyping (12%) than leopards (7%) during daylight hours. Stress levels assessed using FCM revealed that tigers (23.6 ± 1.62 ng/g) had marginally lower level of corticosterone metabolites than leopards (27.2 ±1.36 ng/g). Stereotypic behaviour increased significantly with FCM level when the effect of heath status was controlled in tigers, and the effects tree cover, stone, den and keeper attitude controlled in leopards. Comparison of stereotypes of tigers with various biological and environmental factors using binary logistic regression revealed that stereotypic prevalence decreased with increased enclosure size, and enclosure enrichments like presence of pools and stones, when managed socially with conspecifics, and with positive keeper attitude, these factors accounting for 43% of variations in stereotypic prevalence among tigers. Stereotype among leopards was significantly absent when associated with increased tree cover and presence of pool, and den in the enclosure, age and among zoo-born than wild-born ones. These factors explain 81% of variations in stereotypic prevalence in them. A comparison of FCM levels with context-dependent factors revealed that stress levels among tigers decreased significantly with enclosure size and with individuals from nil to low, and severity of health issues. These factors explain 64% of variations in FCM levels. In leopards, the presence of stones in the enclosure and keepers with positive attitude resulted in significant decrease in FCM levels, these factors together accounting for 94% of variations. Multiple regressions on selected variables based on Factor Analysis of Mixed Data showed that in tigers the intensity of stereotype decreased significantly with enclosure size, sociality and positive keeper attitude and FCM level with health problems. Similarly, analyses in leopards revealed that intensity of stereotype decreased significantly with tree cover, age and FCM level with positive kee...

Effects of a combined enrichment intervention on the behavioural and physiological welfare of captive Asiatic lions (Panthera leo persica)

“…The Asiatic lion conservation breeding programme has successfully maintained a viable captive population insulated from stochastic ecological events. Most research pertaining to captive Asiatic lions investigate their genetic and demographic status (Bagatharia et al, 2013;Pastorino et al, 2017) with only a handful mentioning their welfare (Goswami et al, 2020;Mallapur et al, 2002;Pastorino et al, 2017;Vaz et al, 2017). Our study is the first to assess the effects of enrichment protocols on the welfare of captive Asiatic lions.…”

“…The National Zoo Policy of India (MoEF,India, 1998) espouses animal welfare with captive animal management, yet welfare-centric management protocols remain divorced from husbandry practices across several zoos. Although few and far between, welfare research from Indian zoos report a prevalence of stereotypic behaviours (Goswami et al, 2020;Mallapur et al, 2007;Sanyal, 1892;Vaz et al, 2017) and elevated faecal corticosterone levels (Vaz et al, 2017) across several captive felids, and prescribe specie-appropriate enclosure design and enrichment interventions as remedial measures (Goswami et al, 2020;Mallapur et al, 2007;Vaz et al, 2017). Enrichment interventions have been shown to improve welfare conditions in several captive felids including African lions (Mellen and Shepherdson, 1997;Powell, 1995;Skibiel et al, 2007), yet enrichment protocols are seldom incorporated in the daily management of captive Asiatic lions at Indian zoos.…”

“…In this study, we measured two traditional negative welfare parameters like ARB (Mason and Latham, 2004) and faecal corticosterone levels (Schildkraut, 2016;Vaz et al, 2017) along with two positive welfare indicators (Miller et al, 2020) viz., spread of participation index (SPI) (Cabana et al, 2018;Powell, 1995) and behaviour diversity (Pastorino et al, 2017). Previous studies on captive African lions that establish the positive effects of enrichment interventions have primarily relied on behavioural welfare indices (Martínez-Macipe et al, 2015;Ncube and Ndagurwa, 2010;Powell, 1995;Regaiolli et al, 2019;Van Metter et al, 2008).…”

“…We measured faecal corticosterone metabolites of all subjects to contrast the physiological impacts of the enrichment interventions on control and test subjects. Faecal corticosterone is a reliable physiological indicator of stress and compromised welfare in captive felids (Ruskell et al, 2015;Schildkraut, 2016;Vaz et al, 2017;Young et al, 2004). We collected two fresh faecal samples/week from each subject (both control and test) during the entire study period (preenrichment and post-enrichment).…”

Conservation Physiology of Tigers in Zoos: Integrating Stress Physiology and Behaviour to Monitor Their Health and Welfare

“…In a recent research, Vaz et al [17] applied the concept of conservation physiology to evaluate the stress biology and stereotypic behaviour of tigers (41 Royal Bengal tigers) across six zoos in India. We used non-invasive stress hormone monitoring using faecal corticosterone enzyme immunoassays to quantify the levels of stress in the studied tigers.…”