Abstract
Identifying the consequences of tropical forest degradation is essential to mitigate its effects upon forest fauna. Large forest-dwelling mammals are often highly sensitive to environmental perturbation through processes such as fragmentation, simplification of habitat structure, and abiotic changes including increased temperatures where the canopy is cleared. Whilst previous work has focused upon species richness and rarity in logged forest, few look at spatial and temporal behavioural responses to forest degradation. Using camera traps, we explored the relationships between diel activity, behavioural expression, habitat use and ambient temperature to understand how the wild free-ranging Bornean banteng (Bos javanicus lowi) respond to logging and regeneration. Three secondary forests in Sabah, Malaysian Borneo were studied, varying in the time since last logging (6–23 years). A combination of generalised linear mixed models and generalised linear models were constructed using >36,000 trap-nights. Temperature had no significant effect on activity, however it varied markedly between forests, with the period of intense heat shortening as forest regeneration increased over the years. Bantengs regulated activity, with a reduction during the wet season in the most degraded forest (z = -2.6, Std. Error = 0.13, p = 0.01), and reductions during midday hours in forest with limited regeneration, however after >20 years of regrowth, activity was more consistent throughout the day. Foraging and use of open canopy areas dominated the activity budget when regeneration was limited. As regeneration advanced, this was replaced by greater investment in travelling and using a closed canopy. Forest degradation modifies the ambient temperature, and positively influences flooding and habitat availability during the wet season. Retention of a mosaic of mature forest patches within commercial forests could minimise these effects and also provide refuge, which is key to heat dissipation and the prevention of thermal stress, whilst retention of degraded forest could provide forage.
Highlights
Tropical forests harbour much of the world’s biodiversity and provide important ecosystem services [1], yet are increasingly impacted by selective logging and conversion to agricultural plantations [2]
In light of the extensive forest degradation in Sabah and induced changes in behaviour observed in tropical mammals following timber harvesting, this study focused on the impacts of logging on the Bornean banteng, and used camera traps to conduct the first behavioural study on this species
The least captures were obtained in Tabin Wildlife Reserve (TWR) (48 captures/9.3% of the total) it had the highest survey effort (18,112 nights) and the most camera trap stations (176 stations), whereas the most captures were recorded in Malua Forest Reserve (MFR) (313 captures/63%) (Table 1)
Summary
Tropical forests harbour much of the world’s biodiversity and provide important ecosystem services [1], yet are increasingly impacted by selective logging and conversion to agricultural plantations [2]. Our knowledge of the impacts of selective logging on vertebrate biodiversity is limited to a few taxa [2], and of the studies conducted, the majority focus on biodiversity metrics such as species richness [2,7], rather than behavioural adaptations to post-logging conditions. Considering that mammals are generally more sensitive to forest disturbance than taxa such as plants, invertebrates and birds [9], the impacts of timber harvesting may be evident in their behaviour sooner, making them more useful taxa for assessing the consequences. It is likely that changes in their community are induced by the logging activity and by the subsequent decades of forest regeneration [9,10]. Increases in species abundance and richness have been documented for some mammals [17] and birds [15]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
