Habitat associations of the Sunda stink-badger Mydaus javanensis in three forest reserves in Sabah, Malaysian Borneo

The Sunda stink-badger Mydaus javanensis is one of the most frequently recorded carnivore species in portions of Sabah, Malaysian Borneo. However, its current distribution on Borneo is patchy, with recent records lacking from areas where the species was previously considered common. We assessed the hypothesis that occurrence of Sunda stink-badgers is restricted to areas of high earthworm density. We also assessed the influence of forest disturbance on occurrence, as the species is thought to be disturbance-tolerant. We compiled camera-trap data from three commercial forest reserves in central Sabah collected during 2008-2010 and 2014-2015. We used single season occupancy modeling to estimate probability of occupancy and detection. We obtained 323 detections of Sunda stink-badger over 19,875 trap-nights. We found no fine-scale association between occurrence and earthworm abundance, suggesting that Sunda stink-badgers have broader diets than currently assumed, or that earthworm density potentially influences their occurrence at larger scales. The influence of forest disturbance on occurrence was mixed; although our results suggested that Sunda stink-badgers might have a higher probability of occupancy in more disturbed forests, it is possible that a disturbance threshold exists where extreme forest conversion (e.g., oil palm plantations, human settlements) results in lower occupancy. We did not find strong associations with proximity to water, oil palm plantation, bare earth, or shrub landcovers, suggesting that Sunda stink-badgers are not affected by edge effects or the proximity of disturbed areas. Despite our large dataset across three forest reserves, this study is only a first step in understanding the current irregular distribution of Sunda stink-badgers on Borneo. Further studies across a larger gradient of habitat disturbance are needed to determine potential habitat disturbance thresholds, which will aid in management of this species as the landscape on Borneo continues to undergo anthropogenic change.