Vinitpornsawan & Fuller: Predator and prey behaviours in Thailand Conservation & Ecology RAFFLES BULLETIN OF ZOOLOGY 68: 118–131 Date of publication: 8 April 2020 DOI: 10.26107/RBZ-2020-0013 http://zoobank.org/urn:lsid:zoobank.org:pub:ABF4C425-5FAA-40F9-A4EC-C4DF0DAB51C6 Spatio-temporal correlations of large predators and their prey in western Thailand Supagit Vinitpornsawan1,2 & Todd K. Fuller1* Abstract. The coexistence of predators with similar morphology can be achieved by avoidance through behavioural, temporal and spatial segregation, which separates niches and reduces competition. Partitioning of space and time can reduce competition by decreasing the frequency of interspecific encounters that exploit a common resource base. We investigated temporal and spatial partitioning of tigers (Panthera tigris), leopards (Panthera pardus), dholes (Cuon alpinus), and their ungulate prey in Thung Yai Naresuan (East) Wildlife Sanctuary in western Thailand from April 2010 to January 2012. We collected camera trap data from 106 locations over 1,817 trap nights. Kernel density estimation and Spearman’s rank correlation were used to quantify temporal and spatial activity patterns. Pianka’s index was used to investigate the temporal and spatial overlap for each species pair. Tigers (crepuscular activity pattern) showed no temporal correlation with leopards (mostly diurnal) or dholes (strongly diurnal), but leopard activity appeared to correlate positively with dhole activity. Tigers exhibited temporal overlap with larger gaur (Bos gaurus) and sambar (Rusa unicolor); leopards did so with barking deer (Muntiacus muntjak) and wild boar (Sus scrofa); and dholes did so with barking deer and wild boar. The spatial correlations of tigers, leopards, and dholes did not significantly overlap, though numerically overlap was higher between felids than with the canid. None of the three predators significantly correlated with prey distribution, except for dholes with sambar. Our findings suggest that tigers, leopards, and dholes co-occur with spatial and temporal partitioning due to differences in prey activity and low overlap in space use correlated to prey preference. The partition in space and time between tigers and leopards can minimise their competition-associated prey activity, while leopards and dholes seem to be more generalist and not spatially correlated with each other. Key words. activity, tiger, leopard, dhole, gaur, sambar, Malayan tapir, barking deer, wild boar, camera trap INTRODUCTION Predators affect prey populations and communities by direct and indirect effects on prey behaviours and life histories Interaction between species and the distribution of resources (Bolnick & Preisser, 2005). Selective predation on prey characterise ecological systems and provide essential may result from predators preferring prey of a certain size, information needed to understand the roles of species in behaviour, time, encounter rate, vulnerability, and predation communities (Schoener, 1974; Thompson, 1982). Spatial risk (Emlen, 1966; Polisar et al., 2003; Creel et al., 2005; and temporal partitioning is a viable strategy for minimising Jenny & Zuberbühler, 2005). This can cause prey to exhibit resource competition between species and increasing predator-avoidance behaviour by shifting to other food coexistence (Pianka, 1967; Thompson, 1982; Ramesh et patches or feeding times, or even aggregating into groups al., 2012). In general, activity patterns and spatial use for to repel the predators (Abrams, 1984; Overdorff, 1988; each species are influenced by several factors, which include Palomares & Caro, 1999; Eccard et al., 2008). Over time, physiological adaptations, food availability, distribution these interactions can result in the evolution of physical and pattern, human disturbance, and life-history strategies behavioural traits (Dawkins & Krebs, 1979). (Karanth & Sunquist, 2000). However, several predatory species hunting in the same area Interaction between carnivores and herbivores are can increase the pressure on prey populations (Johnsingh, characterised in terms of predator and prey interactions. 1992). The coexistence of predators with similar morphology can be achieved by avoidance through behavioural, habitat, temporal, and spatial segregation (Schaller, 1972; Malcolm & van Lawick, 1975; Ramesh, 2010; Ramesh et al., 2012). Accepted by: Norman Lim T-Lon Such differences in activities separate niches and reduce 1Department of Environmental Conservation, University of Massachusetts, Amherst, competition, presumably allowing the coexistence of * MA 01003 USA; Email: [email protected] ( corresponding author) sympatric living species (Bekoff et al., 1984; Sunquist & 2Wildlife Conservation Office, National Parks, Wildlife and Plant Conservation Department, 61 Paholyathin Rd., Chatujak, Bangkok 10900 Thailand Sunquist, 1989). © National University of Singapore ISSN 2345-7600 (electronic) | ISSN 0217-2445 (print) 118 RAFFLES BULLETIN OF ZOOLOGY 2020 Fig. 1. Thung Yai Naresuan (East) Wildlife Sanctuary (TYNE), Thailand. 119 Vinitpornsawan & Fuller: Predator and prey behaviours in Thailand Tigers (Panthera tigris), leopards (Panthera pardus), and Data collection. Data were recorded by 106 camera traps dholes (Cuon alpinus) selectively kill prey types of different (Stealth Cam I590 with 5.0 megapixels, Grand Prairie, TX; species, size, and age-sex classes, facilitating their coexistence and Bushnell Trophy Cam infrared with 8.0 megapixels, through ecological separation (Johnsingh, 1992; Karanth Overland Park, KS) for a total of 1,817 trap days from April & Sunquist, 1995, 2000). Ramesh et al. (2012) found that 2010 to January 2012. Cameras were set to operate 24 hours dholes were temporally segregated from tigers and leopards, per day with three images per trigger, with a one-minute delay while spatial overlap occurred with leopards but not with for Stealth Cams (minimum setting) and a 30-second delay tigers. Partitioning of space and time can reduce competition for Bushnell Trophy Cams to maximise animal detection. All by decreasing the frequency of interspecific encounters that camera trap stations contained a pair of cameras, one of each exploit a common resource base (Kronfeld-Schor & Dayan, type to control for detection biases inherent in the different 2003; Ramesh et al., 2012). In Thailand, diet and habitat camera models at the location. The units were installed facing partitioning between these three main predators and their prey each other on both sides of wildlife trails. Each camera trap have previously been reported (Rabinowitz, 1989; Rabinowitz was placed 0.4–0.5 m from the ground and secured to a tree. & Walker, 1991; Grassman, 1999; Ngoprasert et al., 2007; All vegetation and debris were cleared from the field of view Simcharoen et al., 2008; Jenks et al., 2012), but less is known so that both medium and large animals had the opportunity about the behavioural mechanisms underlying temporal and to be photographed. Cameras were deployed in the field spatial partitioning within this group. These large carnivores for 15–20 days before batteries and memory cards were are also known to occupy Thung Yai Naresuan (East) Wildlife replaced. We ensured spatial and temporal independence by Sanctuary, but the activity patterns of predator and prey within minimising trap spacing between camera stations to 2 km the sanctuary are poorly understood. Thus, this study aims to (Fig. 2). No baits or lures were used with the camera traps. enhance our understanding of the coexistence of carnivores Each trap location was checked on a weekly basis to reduce and their prey in the sanctuary, by using camera traps to: 1) their down time from the risks of interference (from humans investigate spatial and temporal activity patterns, 2) compare and large mammals) and to replace batteries and the memory spatial and temporal activity overlap, and 3) evaluate the card when necessary. We selected camera sites based on the avoidance among species through the diel cycle. presence (scats, scrapes, pugmarks, and urination sites) of tigers, leopards, and dholes, and their main prey signs (dung, footprints, calls, and sightings). We placed each camera trap MATERIAL AND METHODS where trails merged or where no alternative trails existed to increase the probability of capturing our target species. Study site. This study was conducted in Thung Yai Naresuan (East) Wildlife Sanctuary, located in the Western Forest Activity patterns were extracted from the camera data for three Complex (WEFCOM) along the Thailand-Myanmar border. predators (tigers, leopards, and dholes) and their five major The sanctuary is adjacent to Huai Kha Khaeng Wildlife prey species: gaur (Bos gaurus), sambar (Rusa unicolor), Sanctuary, which is located at the core of the WEFCOM barking deer (Muntiacus muntjac), wild boar (Sus scrofa), and was designated as a Natural World Heritage Site in 1991 and Malayan tapir (Tapirus indicus), based on an earlier food (Buergin, 2001; WEFCOM, 2004) (Fig. 1). The Thung Yai habits study in the adjacent protected area (Phetdee, 2000). Naresuan Wildlife Sanctuary contains a variety of forest Each photograph was stamped with the time and date. To types, including mixed deciduous (45%), dry evergreen avoid pseudo-replications, we considered the first capture of forest (31%), and hill evergreen forest (15%) (Nakhasathien the animal as an independent record (Yasuda, 2004; Ramesh & Stewart-Cox, 1990). Secondary forest of varying stages of et al., 2012). Any species captured