NATURAL HISTORY OBSERVATIONS OF THE FOUR-HORNED ANTELOPE 72 J. Bombay Nat. Hist. Soc., 106 (1), Jan-Apr 2009 Journal of the Bombay Natural History Society, 106(1), Jan-Apr 2009 72-82 NATURAL HISTORY OBSERVATIONS OF THE FOUR-HORNED ANTELOPE TETRACERUS QUADRICORNIS KOUSTUBH SHARMA 1 , ASAD R. RAHMANI 2 AND RAGHUNANDAN SINGH CHUNDAWAT 3 1 Snow Leopard Trust, 4649 Sunnyside Avenue, #325 North Suite, Seattle, USA. Email: koustubhsharma@gmail.com 2 Bombay Natural History Society, Hornbill House, S.B. Singh Road, Mumbai 400 001, Maharashtra, India. Email: bnhs@bom3.vsnl.net.in 3 BAAVAN (Baagh Aap Aur Van), S-17 Panchsheel Apartments, Panchsheel Enclave, New Delhi 110 016, India. Email: raghu.baavan@gmail.com The Four-horned Antelope is endemic to the Indian subcontinent and is defined as data deficient by IUCN. It is found mainly in forest habitats and is usually solitary. A four-year long study was conducted on the species in Panna National Park, Madhya Pradesh, during which behavioural observations were made using opportunistic focal sampling, mapping and monitoring middens, and cafeteria experiments. A total of 2,902 minutes of cumulative observations of the Four- horned Antelope were made in the field, including 352 events when anti-predatory behaviour was recorded. It was found that the species had a preference for browsing over grazing. It was found using closed canopy thickets, with dense undergrowth or grass cover, for resting unlike Chinkara, which is a sympatric antelope of the same size. The behavioural observations were restricted to the more obvious behaviours, but provided us with a good opportunity to document these for the first time. These include mating, inter and intra-specific interactions, and anti-predatory behaviour. Data on midden locations and their usage over time were also collected to understand the stimulus behind defecation by adults and young ones on middens. It was found that while the Four-horned antelope has a peculiar anti-predatory behaviour where it prefers to hide than run, making it conspicuous and this possibly affected its choice of habitat. The middens were found to be randomly placed in space and their usage pattern indicated that they were used as points of communication between conspecifics of different age and sex groups. Key words: Four-horned antelope, behaviour, Panna National Park, tropical dry deciduous forest, middens, anti-predatory behaviour INTRODUCTION Studying the behaviour of animals in the wild provides useful inputs for their management (Leuthold 1977; Kilgo et al. 1998). The pattern of usage of habitats by animals differs greatly with activity. For many species of animals, the behaviour changes to a great extent with different levels of anthropogenic pressure (Kilgo et al. 1998; Bolhuis and Giraldeau 2005; Rabin 2003). While almost all census methodologies rely on some basic understanding of animal behaviour, the reaction of animals to environmental conditions, degree of adaptability to different circumstances, and conflict with humans can be best understood by gaining an in-depth knowledge of their behaviour. Behavioural traits of living species provide useful information about their evolution (Janis 1981, 1990), and about other closely related or sympatric species that have gone extinct. Behavioural ecology also provides an insight into a species’ relationship with other ecological and evolutionary features, such as morphology, grouping tendencies and niche occupancy. The Four-horned Antelope Tetracerus quadricornis is endemic to the Indian subcontinent, being found only in India and a few pockets of Nepal. Due to its preference for forested and undulating terrain (Prater 1980) and solitary living, it is considered one of the most elusive antelopes in India. It was considered data deficient by IUCN (Rahmani 2001) as there was little information available about its behaviour and ecology other than some observations made by Berwick (1974) in Gir, and by Bhaskaran (1999) and Kannan (1999) in Mudumalai. Apart from these studies, there were only a few historic records that discuss the distribution and behaviour of the Four-horned Antelope in greater detail (Jerdon 1867; Blanford 1888-1891; Brander 1923; Prater 1980). The Four-horned Antelope differs in behaviour and habitat preference from the other five antelope species found in India. It is found predominantly in forest habitats, whereas the Nilgai Boselaphus tragocalemus uses forested and open habitats alike. The Chinkara Gazella bennettii and Blackbuck Antilope cervicapra are restricted to open habitats (Schaller 1967; Ranjitsinh 1982; Rahmani 1990a,b; Rahmani and Sankaran 1991; Isvaran 2005; Alfred et al. 2001), while the Chiru Pantholops hodgsonii and Tibetan Gazelle Procapra picticaudata dwell in the Himalayan mountain ranges that are scantily vegetated (Prater 1980; Menon 2003). The Four- horned Antelope is usually solitary but can be seen occasionally in loosely associated groups of three to five animals. The other antelopes usually have larger mean group sizes, with the exception of the Chinkara, which is found in smaller groups. However, even the Chinkara can be seen in groups as large as 17 in summer (Rahmani 1990b).