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Sarawak is the largest state in the megadiverse country of Malaysia. Its rich biodiversity is threatened by land-use change and hunting, with mammalian carnivores particularly affected. Data on the ecology, occurrence and distribution of small carnivores are crucial to inform their effective conservation, but no large-scale assessments have previously been conducted in Sarawak. Here we examine the status of the five species of felids in Sarawak based on data from camera-trap studies over 17 years (May 2003–February 2021) across 31 study areas, including protected areas of various sizes, production forests and forest matrix within oil palm plantations. Felids were detected at 39% of 845 camera stations. The marbled cat Pardofelis marmorata and Sunda clouded leopard Neofelis diardi had higher probabilities of occurrence in protected than unprotected areas, and vice versa for the leopard cat Prionailurus bengalensis and bay cat Catopuma badia. The marbled and bay cats were mostly diurnal, and the leopard cat was predominantly nocturnal; activity patterns did not substantively differ between protected and unprotected sites. The probabilities of occurrence of marbled and bay cats increased with greater distance from roads. The leopard cat and flat-headed cat Prionailurus planiceps were more likely, and the clouded leopard less likely, to occur near rivers. Flat-headed cats preferred peat swamp forest, bay cats lowland forest, and marbled cats and clouded leopards occurred in both lowland and montane forest. Felids may tolerate higher elevations to avoid anthropogenic disturbance; therefore, it is critical to preserve lowland and mid-elevation habitats that provide refugia from climate change and the destruction of lowland habitat. [ABSTRACT FROM AUTHOR]

Tropical regions are undergoing rapid land use change, with major implications for global biodiversity. Selective logging and agroforestry are particularly widespread across tropical forests, often occurring in close proximity. But while a number of studies have addressed their impacts separately, few have directly compared how they influence forest vertebrates. Here, we assessed the occurrence of medium‐ to large‐bodied mammals in logged forest, unlogged forest, and agroforestry areas in three study areas in interior Sarawak, Malaysian Borneo. We detected 34 species across 99 camera trap locations and used multi‐species occupancy models to estimate species‐specific occurrence while accounting for imperfect detectability, spatial autocorrelation, natural habitat heterogeneity, and metrics of site accessibility (distance to human infrastructure) as proxies for potential hunting pressure. We found that species occurrences were unaffected by the distance to the nearest road or village and only responded to elevation and the distance to the nearest river in a single species each. Detection rates tended to vary with micro‐habitat characteristics such as the size of tree stumps and the prevalence of trees and rattan palms, which are often not considered in camera‐based occupancy studies. Occurrence rates of five species varied across habitat types but were not detectably lower in agroforestry sites than in unlogged forest for any species. Our results indicate that without unsustainable hunting, agroforestry and logged forest provide usable habitat for some, though not all, rainforest mammals. We also suggest that camera trap studies may benefit from the incorporation of fine‐scale habitat information into detectability estimation. Abstract in Malaysian is available with online material. [ABSTRACT FROM AUTHOR]

Conservation outcomes could be greatly enhanced if strategies addressing anthropogenic land‐use change considered the impacts of these changes on entire communities as well as on individual species. Examining how species interactions change across gradients of habitat disturbance allows us to predict the cascading consequences of species extinctions and the response of ecological networks to environmental change.We conducted the first detailed study of changes in a commensalist network of mammals and dung beetles across an environmental disturbance gradient, from primary tropical forest to plantations, which varied in above‐ground carbon density (ACD) and mammal communities.Mammal diversity changed only slightly across the gradient, remaining high even in oil palm plantations and fragmented forest. Dung beetle species richness, however, declined in response to lower ACD and was particularly low in plantations and the most disturbed forest sites. Three of the five network metrics (nestedness, network specialization and functionality) were significantly affected by changes in dung beetle species richness and ACD, but mammal diversity was not an important predictor of network structure. Overall, the interaction networks remained structurally and functionally similar across the gradient, only becoming simplified (i.e. with fewer dung beetle species and fewer interactions) in the most disturbed sites.We suggest that the high diversity of mammals, even in disturbed forests, combined with the generalist feeding patterns of dung beetles, confer resilience to the commensalist dung beetle–mammal networks.This study highlights the importance of protecting logged and fragmented forests to maintain interaction networks and potentially prevent extinction cascades in human‐modified systems. [ABSTRACT FROM AUTHOR]

Selective logging is very widespread across the tropics and can alter the habitat for myriad wildlife species. But while many studies have assessed the impacts of past logging on forest animals, far fewer have investigated how species respond to logging while the timber operations are actually going on. This is an important knowledge gap because, considering the prevalence of logging across the world, numerous areas will be undergoing active extraction at any given time. We compared the occurrence and diel activity patterns of individual species of medium- to large-bodied terrestrial mammals, as well as the richness of the entire assemblage, among sites that were either unlogged, had been logged historically, or had ongoing 'reduced impact' timber extraction in the Kapit Region of Sarawak, Malaysian Borneo. We found no significant differences in estimated occupancy or activity patterns of particular species, or in overall species richness, among logging treatments. Across sites, species richness in this area appeared to be as high as or higher than in many other parts of the state, including some protected areas. Though monitoring is needed to assess potential long-term impacts, our results suggest that reduced-impact logging could allow economic development that is sustainable for many wildlife populations. [ABSTRACT FROM AUTHOR]

Periods of extreme food abundance, such as irregular masting events, can dramatically affect animal populations and communities, but the extent to which anthropogenic disturbances alter animal responses to mast events is not clear. In South‐East Asia, dipterocarp trees reproduce in mast fruiting events every 2–10 years in some of the largest masting events on the planet. These trees, however, are targeted for selective logging, reducing the intensity of fruit production and potentially affecting multiple trophic levels.Moreover, animal responses to resource pulse events have largely been studied in systems where the major mast consumers have been extirpated. We sought to evaluate the influence of human‐induced habitat disturbance on animal responses to masting in a system where key mast consumers remain extant.We used motion‐triggered camera traps to quantify terrestrial mammal and bird occurrences in Sabah, Malaysian Borneo, relative to variation in fruit biomass from 69 plant families during a major (2014) and minor (2015) masting event and a non‐mast year (2013), in both logged and unlogged forests.Bearded pigs (Sus barbatus) showed the clearest responses to masting and occurrence rates were highest in unlogged forest in the year following the major mast, suggesting that the pulse in fruit availability increased immigration or reproduction. We also detected local‐scale spatial tracking of dipterocarp fruits in bearded pigs in unlogged forest, while this was equivocal in other species. In contrast, pigs and other vertebrate taxa in our study showed limited response to spatial or temporal variation in fruit availability in logged forest.Our findings suggest that vertebrates, namely bearded pigs, may respond to masting via movement and increased reproduction, but that these responses may be attenuated by habitat disturbance. [ABSTRACT FROM AUTHOR]

Vertebrate granivores destroy plant seeds, but whether animal-induced seed mortality alters plant recruitment varies with habitat context, seed traits, and among granivore species. An incomplete understanding of seed predation makes it difficult to predict how widespread extirpations of vertebrate granivores in tropical forests might affect tree communities, especially in the face of habitat disturbance. Many tropical forests are simultaneously affected by animal loss as well as habitat disturbance, but the consequences of each for forest regeneration are often studied separately or additively, and usually on a single plant demographic stage. The combined impacts of these threats could affect plant recruitment in ways that are not apparent when studied in isolation. We used wire cages to exclude large (elephants), medium, (sambar deer, bearded pigs, muntjac deer), and small (porcupines, chevrotains) ground-dwelling mammalian granivores and herbivores in logged and unlogged forests in Malaysian Borneo. We assessed the interaction between habitat disturbance (selective logging) and experimental defaunation on seed survival, germination, and seedling establishment in five dominant dipterocarp tree species spanning a 21-fold gradient in seed size. Granivore-induced seed mortality was consistently higher in logged forest. Germination of unpredated seeds was reduced in logged forest and in the absence of small to large-bodied mammals. Experimental defaunation increased germination and reduced seed removal but had little effect on seed survival. Seedling recruitment however, was more likely where logging and animal loss occurred together. The interacting effects of logging and hunting could therefore, actually increase seedling establishment, suggesting that the loss of mammals in disturbed forest could have important consequences for forest regeneration and composition. [ABSTRACT FROM AUTHOR]

Habitat corridors are important tools for maintaining connectivity in increasingly fragmented landscapes, but generally they have been considered in single-species approaches. Corridors intended to facilitate the movement of multiple species could increase persistence of entire communities, but at the likely cost of being less efficient for any given species than a corridor intended specifically for that species. There have been few tests of the trade-offs between single- and multispecies corridor approaches. We assessed single-species and multispecies habitat corridors for 5 threatened mammal species in tropical forests of Borneo. We generated maps of the cost of movement across the landscape for each species based on the species' local abundance as estimated through hierarchical modeling of camera-trap data with biophysical and anthropogenic covariates. Elevation influenced local abundance of banded civets ( Hemigalus derbyanus) and sun bears ( Helarctos malayanus). Increased road density was associated with lower local abundance of Sunda clouded leopards ( Neofelis diardi) and higher local abundance of sambar deer ( Rusa unicolor). Pig-tailed macaque ( Macaca nemestrina) local abundance was lower in recently logged areas. An all-species-combined connectivity scenario with least-cost paths and 1 km buffers generated total movement costs that were 27% and 23% higher for banded civets and clouded leopards, respectively, than the connectivity scenarios for those species individually. A carnivore multispecies connectivity scenario, however, increased movement cost by 2% for banded civets and clouded leopards. Likewise, an herbivore multispecies scenario provided more effective connectivity than the all-species-combined scenario for sambar and macaques. We suggest that multispecies habitat connectivity plans be tailored to groups of ecologically similar, disturbance-sensitive species to maximize their effectiveness. Evaluación de la Conectividad de Terrenos Multiespecie en una Comunidad Tropical de Mamíferos [ABSTRACT FROM AUTHOR]

Selective logging is one of the most widespread disturbances to tropical forests worldwide, yet its impacts on large mammals remain poorly understood. We used camera trapping and hierarchical models to compare local abundance of a variety of terrestrial mammal species in Borneo between selectively logged and unlogged forest, and to assess the impacts of edge effects. Our methods circumvent confounding factors that have plagued previous assessments of logging impacts by explicitly accounting for differential detection probability among habitats, separating the effects of hunting from those of logging-induced habitat disturbance, and explicitly measuring the distances over which edge effects occur. We found that mammalian carnivore species were either largely or completely confined to primary forest, although habitat use for the Sunda clouded leopard ( Neofelis diardi ) increased toward the ecotone. Several large ungulates, however, were either completely (elephant Elephas maximus and banteng Bos javanicus ) or mostly (sambar Rusa unicolor ) found in logged forest. This suggests that, in the absence of hunting, disturbed habitats can be important for the conservation of certain endangered and vulnerable species. Sambar and muntjac ( Muntiacus spp.) both strongly avoided habitat edge in logged forest and primary forest, respectively. Lower habitat use by these species persisted 2–4 km from the habitat boundary – farther than has been observed for the infiltration of other edge effects such as canopy desiccation. Such avoidance of ecotones implies that 20–40% of the intact primary forest habitat in our study area is actually degraded “edge habitat” from the point of view of primary forest specialists. Our results suggest that, while selectively logged forests retain conservation value for certain large mammal species, it is critical that thresholds in logging intensity be identified so as to avoid declines in habitat use by taxa, such as carnivores, which appear intolerant of intensive logging pressure. [ABSTRACT FROM AUTHOR]

Abstract: When humans reduce top carnivore abundance in insular systems, herbivore populations may increase, with cascading impacts on the community. But the prevalence of such “trophic release” effects in non-insular ecosystems remains little known, particularly in tropical ecosystems. We assessed whether areas with low top carnivore abundance were associated with greater abundance of herbivores across seven rainforest study areas in Malaysian Borneo. We deployed 134 camera-trap stations and analyzed the resulting photographic detections from 16,608 trap-days using multi-species occupancy models that estimate abundance while accounting for imperfect detectability. Estimated local abundance of Sunda clouded leopards (Neofelis diardi), the apex mammalian predator, varied from 0.0 to 3.5 individuals per camera location. Clouded leopard abundance was not negatively correlated with the abundance of any of the four prey species that we analyzed. Rather, sites with few or no clouded leopards also had the lowest estimated abundance of pig-tailed macaques (Macaca nemestrina). Estimated abundance of muntjac (Muntiacus spp.) and mousedeer (Tragulus spp.) was statistically unrelated to estimated clouded leopard abundance. Bearded pig (Sus barbatus) abundance was likewise unaffected by predator abundance, but pigs appear to live in larger groups when clouded leopards are common, possibly to better defend their young. We found no evidence of trophic release, an important conservation threat in other areas, in this ecosystem, particularly relative to the massive impacts of agricultural conversion, habitat degradation, and unsustainable wildlife exploitation. [Copyright &y& Elsevier]

Many tropical mammals with important functional roles in forest ecosystems are threatened with extinction, yet how they respond to increasingly prevalent habitat disturbance, such as selective logging, is not well understood. We deployed 43 motion-triggered camera traps in 2013 and 2014 in unlogged forest and in a forest logged three decades previously in Malaysian Borneo. We used camera trap photographs to assess whether selective logging influenced the local abundance of medium to large-bodied ground-dwelling mammals. We focused our study on six locally common species: sambar deer, ( Rusa unicolor ), yellow muntjac ( Muntiacus atherodes ), chevrotains ( Tragulus spp.), banded civet ( Hemigalus derbyanus ), Malay civet ( Viverra tangalunga ), and pig-tailed macaque (Macaca nemestrina ). Occupancy models were used to estimate local abundance. None of the mammals in our study exhibited decreased abundance in logged forest, although yellow muntjac and pig-tailed macaque were associated with canopy height. Contiguous forest connects these two areas, allowing animal movement between them, potentially explaining the lack of responses. The elapsed time since logging may have further influenced our findings. The effects of logging on mammal local abundance may no longer detectable after 30 years. Overall, our results demonstrate the importance of regenerating forest as habitat for medium- to large-sized mammal species. [ABSTRACT FROM AUTHOR]