Behaviour and spatial ecology of the Bornean elephant (Elephas maximus borneensis) in Lower Kinabatangan, Sabah, Malaysia Borneo

• Main Author: Othman, Nurzhafarina
• Published: Cardiff University 2017
• Online Access: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.738373

The Bornean subspecies of Asian elephant (Elephas maximus borneensis) is mainly restricted to Sabah, Malaysia and the survival of these elephants in the wild is being jeopardized primarily through a combination of habitat loss, conflicts with people and low genetic diversity. Lower Kinabatangan Floodplain (LKF) which holds between 200 and 250 elephants is isolated from the other populations in Sabah and highly vulnerable to both anthropogenic and non-anthropogenic pressures such as climate change and further encroachments to their natural habitat. Solutions to these challenges require information on the factors affecting the movement and behaviour of the species. This thesis examines the behavioural and spatial ecology of the Bornean elephant in the Lower Kinabatangan region of Sabah, in Malaysian Borneo. Elephants were monitored visually, and to facilitate remote-monitoring of movement, six female elephants were fitted with satellite collars during the flooding and non-flooding seasons of 2011-2012 (n=3 individuals) and 2013-2014 (n=3 individuals) respectively. In Chapter 2, the seasonal variations in spatial utilization distribution were quantified using analytical methods such as dynamic Brownian Bridge Movement modelling (dBBMM) and Classification and Regression Tree (CART). This analysis showed that the size of utilization distribution (UD) varied significantly between individuals and seasonally. In both seasons, the elephants were observed to maintain their UD close to the river. In the flooding season elephants were less selective about their space use and were more predictable in their movements than in the non-flooding season and were more mobile in higher elevation and good quality habitats. In the non-flooding season, the utilization distribution of elephants was larger and mostly determined by anthropogenic factors such as roads. The core home range areas of elephants in both seasons mostly reflected the need to satisfy their dietary and water requirements. In Chapter 3, Brownian motion variance generated from the elephants’ movement data was used as a measure of behavioural state relating to motion, to describe the behaviour of the elephants (Chapter 3). Human activities and environmental features were used to explain the changes of motion variance and speed in a fragmented landscape. The data were analysed using generalized additive mixed model (GAMMs). This analysis revealed that elephant movement dynamics and speed show significant temporal (diurnal and seasonal) and spatial (between habitat) variation. Finally, in Chapter 4, I carried out the first longitudinal analysis of the activity budget of adult female elephants in the oil palm plantations, freshwater swamp and riparian habitats adjoining the Kinabatangan River, in order to understand how elephant behaviours vary in relation to habitat, time of day, season and group size. We used generalised additive mixed models (GAMMs) to examine how the behaviours of 40 individually-identified adult female elephants (primarily feeding, moving, resting, bathing, social interactions, and vigilance) varied in relation to time of the day, season and group size, in the major habitat types within this landscape. Elephants primarily fed in the morning and evening, and rested in the middle of the day. In oil palm plantations, elephants were observed to associate in smaller groups, and to feed less feed and to socialize less, and to be more restless, vigilant and mobile compared to riparian habitats. A similar comparison between semi swamp and riparian forest showed significantly higher feeding and vigilance behaviour in freshwater swamp forest but no significant difference in resting and moving. Our results show that riparian and seasonal freshwater swamp habitats play an important role as a social arena for the Bornean elephants in LKF, as well as providing food resources and connectivity for movement of elephants across this landscape that is increasingly fragmented by oil palm plantations and other human infrastructure such as roads and bridges. Chapter 5 summarises the main findings of this thesis and the implications for the conservation of the Bornean elephant at the local, national and global scale. These findings together comprise the most detailed account to date of the behaviour and spatial ecology of wild Bornean elephants, and will be used to inform conservation policy (e.g. maintaining connectivity between patches of natural habitat types) and mitigation of human-elephant conflict (e.g. through an improved understanding of daily and seasonal variation in behaviour, and behavioural differences between habitats).