Identifying habitat and understanding movement resistance for the Endangered Bornean bantengBos javanicus lowiin Sabah, Malaysia

Hong Ye Lim,Benoit Goossens,Kalsum M Yusah,Penny C Gardner,Nicola K Abram

doi:10.1017/s0030605318001126

Abstract

AbstractHabitat prioritization and corridor restoration are important steps for reconnecting fragmented habitats and species populations, and spatial modelling approaches are useful in identifying suitable habitat for elusive tropical rainforest mammals. The Endangered Bornean bantengBos javanicus lowi, a wild bovid endemic to Borneo, occurs in habitat that is highly fragmented as a result of extensive agricultural expansion. Based on the species’ historical distribution in Sabah (Malaysia), we conducted camera-trap surveys in 14 forest reserves during 2011–2016. To assess suitable habitat for the banteng we used a presence-only maximum entropy (MaxEnt) approach with 11 spatial predictors, including climate, infrastructure, land cover and land use, and topography variables. We performed a least-cost path analysis usingLinkage Mapper,to understand the resistance to movement through the landscape. The surveys comprised a total of 44,251 nights of camera trapping. We recorded banteng presence in 11 forest reserves. Key spatial predictors deemed to be important in predicting suitable habitat included soil associations (52.6%), distance to intact and logged forests (11.8%), precipitation in the driest quarter (10.8%), distance to agro-forest and regenerating forest (5.7%), and distance to oil palm plantations (5.1%). Circa 11% of Sabah had suitable habitat (7,719 km2), of which 12.2% was in protected forests, 60.4% was in production forests and 27.4% was in other areas. The least-cost path model predicted 21 linkages and a relatively high movement resistance between core habitats. Our models provide information about key habitat and movement resistance for bantengs through the landscape, which is crucial for constructive conservation strategies and land-use planning.

Highlights

Human-induced destruction of natural ecosystems is one of the major threats to global biodiversity (Cincotta et al, ), with c. % of all known species threatened by destructive human activities (IUCN, )
Suitable habitat was highly associated with specific soil types, especially Kalabakan, Labau and Lokan, TABLE 1 Per cent contribution of spatial variables to the habitat suitability model for the Bornean banteng Bos javanicus lowi
Circa % (, km ) of Sabah was predicted to have suitable habitat, c. % of which was within Protected Areas and Protection Forest Reserves, % (, km ) was within Production Forest Reserves, and % (, km ) was outside these areas (Table ; Fig. )

Summary

Introduction

Human-induced destruction of natural ecosystems is one of the major threats to global biodiversity (Cincotta et al, ), with c. % of all known species threatened by destructive human activities (IUCN, ). Endemic species of Borneo are among the most vulnerable to timber extraction, deforestation for oil palm, habitat fragmentation and poaching (Gaveau et al, ; Hoffmann et al, ). Effective protection of these species requires a strategic conservation approach, involving in particular habitat protection and connectivity restoration (Koh & Sodhi, ). Bornean bantengs inhabit primary and secondary dipterocarp and swamp forests and are best described as mixedfeeders (Gardner et al, ). When the ambient temperature is high they rest in the shade of closed canopy forest to reduce heat stress and avoid dehydration (Gardner, ). Deforestation and the establishment of extensive monoculture plantations, especially of oil palm, have resulted in a highly fragmented population (Gardner, )

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