Many plantations in Malaysia and Indonesia (which currently produce over 80% of the global supply of palm oil (FAO, 2014)) practice Integrated Pest Management approaches; they Doxorubicin manufacturer do not routinely apply pesticides and are therefore affected by naturally occurring densities of pests and pest predators (Corley and Tinker, 2003 and Koh, 2008). Forest is commonly retained along waterways in oil palm plantations to maintain water quality, reduce flood risk and prevent soil erosion (e.g. Sabah Water Resources Enactment 1998). However, these riparian reserves can also conserve forest-dependent species not otherwise found in areas of oil palm (Gray, Slade, Mann, & Lewis, 2014). As spillover from forest fragments increases species

richness in adjacent areas of oil palm (Lucey and Hill, 2012 and Lucey et al., 2014) it is possible that the Selleckchem GSK1210151A abundance or diversity of pests and/or pest predators increase with proximity to riparian reserves. However, non-crop habitat can also harbour crop-damaging insects (Naiman & Decamps, 1997) and birds (Deschênes, Bélanger, & Giroux, 2003). Overall, the extent to which riparian reserves support ecosystem services or disservices within agricultural

landscapes remains understudied. Here, we assess whether riparian reserves affect the activity of defoliating pests and their potential predators within an oil palm dominated landscape in Sabah, Malaysia. We hypothesised that proximity to a riparian reserve could either (a) increase predation on pests and decrease herbivory rates, or (b) increase pest activity and herbivory

rates. In addition, as positive relationships have been found between the size and species richness of forest fragments and the richness Metalloexopeptidase of species spilling over into surrounding oil palm (Lucey et al., 2014), we hypothesised that any increase or decrease in pest activity would be enhanced with greater riparian reserve widths. All study sites were located around the Stability of Altered Forest Ecosystems (SAFE) project site in Sabah, Malaysian Borneo (117.50N, 4.60E). Details of the landscape are given in Ewers et al. (2011). We collected data from a total of 14 riverside sites (see Appendix A: Fig. 1) between April and November 2012. Eight sites had a riparian reserve flanking the river (mean forest width measured on one side of the river = 54 m, sd = 38, minimum width = 12 m, maximum width = 101 m. Appendix A: Table 1 gives widths and data on vegetation structure for all sites). All Riparian reserves had been previously logged before conversion to oil palm and were structurally similar to nearby logged forest. Riparian reserve widths varied around the legal requirements for the state of Sabah (20 m either side of rivers wider than 3 m, Sabah Water Resources Enactment 1998) and fall within or above the guidelines specified by the Malaysian National Interpretation of RSPO principles and criteria (RSPO, 2010).