Population density, spatiotemporal use and diet of the leopard cat (Prionailurus bengalensis) in a human-modified succession forest landscape of Singapore

Loss of Sunda clouded leopards and forest integrity drive potential impacts of mesopredator release on vulnerable avifauna

Amongst the unintended consequences of anthropogenic landscape conversion is declining apex predator abundance linked to loss of forest integrity, which can potentially re-order trophic networks. One such re-ordering, known as mesopredator release, occurs when medium-sized predators, also called mesopredators, rapidly increase in abundance following the decline in apex predator abundance, consequently reducing the abundance of mesopredator prey, notably including terrestrial avifauna. We examine the cascading impacts of declining Sunda clouded leopard abundance, itself consequent upon a reduction in forest integrity, on the mesopredator community of Sabah, Malaysia, to determine whether the phenomenon of mesopredator release is manifest and specifically whether it impacts the terrestrial avifauna community of pheasants and pittas. To explore this trophic interaction, we used a piecewise structural equation model to compare changes in the relative abundance of organisms. Our results suggest that loss of forest integrity may have broad impacts on the community and trigger mesopredator release, the two acting additively in their impact on already vulnerable species of terrestrial avifauna: a result not previously documented in tropical systems and rarely detected even on a global scale. The limiting effect that the Sunda clouded leopard has on the Sunda leopard cat could illuminate the mechanism whereby mesopredator release impacts this system. Both Bulwer's pheasant and pittas appear to be significantly impacted by the increase in Sunda leopard cats, while the great argus pheasant shows similar compelling, although not statistically significant, declines as Sunda leopard cats increase. The inverse relationship between Sunda clouded leopards and Sunda leopard cats suggests that if a mesopredator release exists it could have downstream consequences for some terrestrial avifauna. These results suggest the under-studied interface between mammalian carnivores and avifauna, or more broadly species interactions in general, could offer important conservation tool for holistic ecosystem conservation efforts.

Effects of human disturbances on wildlife behaviour and consequences for predator-prey overlap in Southeast Asia

Some animal species shift their activity towards increased nocturnality in disturbed habitats to avoid predominantly diurnal humans. This may alter diel overlap among species, a precondition to most predation and competition interactions that structure food webs. Here, using camera trap data from 10 tropical forest landscapes, we find that hyperdiverse Southeast Asian wildlife communities shift their peak activity from early mornings in intact habitats towards dawn and dusk in disturbed habitats (increased crepuscularity). Our results indicate that anthropogenic disturbances drive opposing behavioural adaptations based on rarity, size and feeding guild, with more nocturnality among the 59 rarer specialists' species, more diurnality for medium-sized generalists, and less diurnality for larger hunted species. Species turnover also played a role in underpinning community- and guild-level responses, with disturbances associated with markedly more detections of diurnal generalists and their medium-sized diurnal predators. However, overlap among predator-prey or competitor guilds does not vary with disturbance, suggesting that net species interactions may be conserved.

Occurrence and temporal overlap of sympatric jungle cats and leopard cats in Parsa‒Koshi Complex, Nepal

Co-occurrence and spatial and temporal overlap of sympatric jungle and leopard cats are influenced by habitat preferences, and interspecific competition. Understanding these factors influence is crucial for developing effective conservation strategies. We conducted a camera survey in Parsa‒Koshi Complex (PKC), Nepal during December 2022-March 2023 to investigate factors influencing occupancy and spatial and temporal overlap between jungle cats (Felis chaus) and leopard cats (Prionailurus bengalensis). The mean detection probability (t = 0.664, p = 0.507) did not differ between jungle cats (p = 0.500 ± 0.289) and leopard cats (p = 0.501 ± 0.288); however, occupancy (t = 31.008, p < 0.001) was greater for jungle cats (ψ = 0.247 ± 0.020) than leopard cats (ψ = 0.178 ± 0.019). Jungle cats and leopard cats were positively associated with large predators, and jungle cats were positively associated with human presence and negatively associated with canopy cover. We observed high diel overlap between leopard cats and jungle cats (Dhat1 = 0.802, norm0CI: 0.720-0.884), with both species largely nocturnal. Co-existence of jungle cats and leopard cats in PKC appears to be facilitated by spatial segregation. These findings provide valuable insights into the complex ecological dynamics and interactions between sympatric jungle and leopard cats.

Singapore's herpetofauna: updated and annotated checklist, history, conservation, and distribution

Given Singapore's location at the confluence of important maritime trading routes, and that it was established as a British East India Company trading post in 1819, it is unsurprising that Singapore has become one of the centres of natural history collecting and research in Southeast Asia. Despite its small size, Singapore is home to a diverse herpetofauna assemblage and boasts a rich herpetological history. The first systematic studies of Singapore's herpetofauna (within the Linnaean binomial framework) date back to Stamford Raffles and the naturalists hired by him who first came to the island in 1819. Specimens that were collected during and after this time were deposited in museums worldwide. Over time, 39 species from Singapore were described as new to science. Due to the entrepôt nature of Singapore with its associated purchasing and trading of specimens (both alive and dead), poor record-keeping, and human introductions, numerous extraneous species from outside of Singapore were reported to occur on the island. Such issues have left a complicated legacy of ambiguous records and taxonomic complications concerning the identity of Singapore's species-rich herpetofauna, many of which were only resolved in the past 30-40 years. By compiling a comprehensive collection of records and publications relating to the herpetofauna of Singapore, we construct an updated and more accurate listing of the herpetofauna of Singapore. Our investigation culminated in the evaluation of 309 species, in which we compiled a final species checklist recognising 166 species (149 native and 17 non-native established species). Among the 149 native species are two caecilians, 24 frogs, one crocodilian, 13 turtles (three visitors), 34 lizards, and 75 snakes. Of the 17 non-native species are five frogs, four turtles, six lizards, and two snakes. The remaining 143 species represent species to be excluded from Singapore's herpetofauna species checklist. For each of the 309 species examined, we provide species accounts and explanatory annotations. Furthermore, we discuss Singapore's herpetofauna from a historical and conservation perspective. Immediate deforestation and nationwide urbanisation following colonisation completely eliminated many species from throughout much of the country and restricted them to small, degraded forest patches. We hope this publication highlights the importance of publishing observations and serves as a valuable resource to future researchers, naturalists, biological consultants, and policy makers in initiating studies on species ecology, distribution, status, and promoting conservation efforts to safeguard Singapore's herpetofauna.

Fine-Scale Interactions between Leopard Cats and Their Potential Prey with Contrasting Diel Activities in a Livestock-Dominated Nature Reserve

Habitat use and the temporal activities of wildlife can be largely modified by livestock encroachment. Therefore, identifying the potential impacts of livestock on the predator-prey interactions could provide essential information for wildlife conservation and management. From May to October 2017, we used camera trapping technology to investigate fine-scale spatiotemporal interactions in a predator-prey system with the leopard cat (Prionailurus bengalensis) as a common mesopredator, and its prey with contrasting activity patterns (i.e., nocturnal rats and diurnal squirrels) in a livestock-dominated nature reserve in Northern China. We found that the prey species showed different habitat preferences with the leopard cats. The nocturnal rats had strong positive effects on the site-use of the leopard cats, while the influence of livestock on the diurnal squirrels' site-use changed from strong positive effects to weak effects as the livestock disturbance increased. The temporal overlap between the leopard cats and the nocturnal rats was almost four times that of the leopard cats and the diurnal squirrels, regardless of the livestock disturbance. Our study demonstrated that the fine-scale spatiotemporal use patterns of the leopard cats were consistent and highly correlated with the nocturnal rats under livestock disturbance. We suggest that appropriate restrictions on livestock disturbance should be implemented by reserve managers to reduce the threat to wildlife and achieve multi-species coexistence.

Fine-Scaled Selection of Resting and Hunting Habitat by Leopard Cats (Prionailurus bengalensis) in a Rural Human-Dominated Landscape in Taiwan

Wildlife is increasingly forced to live in close proximity to humans, resulting in human-wildlife conflict and anthropogenic mortality. Carnivores persisting in human-dominated landscapes respond to anthropogenic threats through fine-scaled spatial and temporal behavioral adjustments. Although crucial for conservation, quantitative information on these adjustments is scarce. Taiwan’s endangered leopard cat occurs in rural human-dominated landscapes with a high anthropogenic mortality risk. To survive, the nocturnal leopard cat needs suitable habitats for foraging and safe refuge for resting during daytime hours when human activity peaks. In this study, we tracked seven VHF-collared leopard cats. To determine habitat selection patterns, we compared land use at nighttime locations and daytime resting sites with random points and fine-scaled vegetation characteristics at daytime resting sites with random points. Leopard cats selected natural habitats for nighttime hunting and avoided manmade and, to a lesser extent, agricultural habitats or used them according to availability. For daytime resting, leopard cats selected natural habitats and, to a lesser extent semi-natural habitats, such as unused land and abandoned orchards. Resting sites were preferentially situated in natural habitats, with little visibility (<2 m), shrubs, reed and stones, away from areas with high levels of human activity. This suggests leopard cats use a proactive strategy to avoid human encounters, which was supported by the reduced temporal overlap with humans and domestic dogs on agricultural land. Resting sites were placed ca. 1 km apart, 12.9 ± 0.3 m (mean ± SE) from the patch’s edges, in patches with a size of 1.21 ± 0.04 ha (mean ± SE). Our results will assist in identifying and preserving suitable resting habitats to support leopard cat conservation.

Combining vertebrate mitochondrial 12S rRNA gene sequencing and shotgun metagenomic sequencing to investigate the diet of the leopard cat (Prionailurus bengalensis) in Korea

The leopard cat (Prionailurus bengalensis), an endangered species in South Korea, is a small feline widely distributed in Asia. Here, we investigated the diet of leopard cats in the inland areas of Korea by examining their fecal contents using vertebrate mitochondrial 12S rRNA gene sequencing and shotgun metagenomic sequencing. Shotgun metagenomic sequencing revealed that the feces were rich in DNA not only of vertebrates but also of arthropods and plants, but care should be taken when using shotgun metagenomic sequencing to identify vertebrates at low taxonomic levels (e.g., genus level), as it was often erroneous. Meanwhile, vertebrate mitochondrial 12S rRNA gene sequencing was found to be accurate in the genus-level identification, as the genera identified were consistent with the Korean fauna. We found that small mammals such as murids were their main prey. By using these two sequencing methods in combination, this study demonstrated that accurate information about the overall dietary content and vertebrate prey of leopard cats could be obtained. We expect that the continued community efforts to expand the genome database of wildlife, including vertebrates, will alleviate the problem of erroneous identification of prey at low taxonomic levels by shotgun metagenomic sequencing in the near future.

Habitat use by the endangered spotted-tailed quoll in a fragmented landscape

The spotted-tailed quoll (Dasyurus maculatus) is an endangered mesopredator endemic to Australia. It is generally considered a forest-dependent species associated with large, intact forested habitats. In Australia’s mainland, quoll research has typically been conducted in contiguous forest, and consequently, the species’ presumed forest-dependency might reflect sampling bias rather than preferred habitat niche. Recent studies have revealed that quolls also persist in fragmented agricultural landscapes, raising questions about their true habitat requirements and preferences. In this study, we investigated quoll habitat use within a fragmented agricultural landscape in mainland Australia. We deployed 42 lured camera traps to determine quoll habitat preferences across four broad vegetation types (open grassland, grassy woodland, dry sclerophyll forest, and wet sclerophyll forest) based on quoll activity and occupancy. Quolls were detected in all vegetation types, and quoll activity indicated a preference for dry sclerophyll forest and grassy woodlands, although this preference varied depending on the time of year. Our results suggest that quoll habitat use in mainland Australia is more flexible than previously assumed, and we recommend further research on factors that may influence habitat preference such as prey availability and seasonal behavior. Understanding the factors that drive habitat use by quolls outside of contiguous forested landscapes will inform and improve conservation and management strategies to ensure critical habitat for the species is protected and retained in an increasingly fragmented landscape.

Density estimates reveal that fragmented landscapes provide important habitat for conserving an endangered mesopredator, the spotted-tailed quoll

Native predators are increasingly exposed to habitat loss and fragmentation globally. When developing conservation and management strategies, it is important to determine whether fragmented landscapes can still support similar predator densities to intact areas, and thereby constitute important habitat for these species. The spotted-tailed quoll (Dasyurus maculatus) is an endangered Australian mesopredator that is often considered to be forest-dependent. While quolls are known to occur in some fragmented forest landscapes, it is unclear whether these areas represent sub-optimal habitat where quolls merely persist, or whether quolls can still occur at densities similar to those observed in intact forest landscapes. We used camera traps to detect quolls in both a fragmented and intact forested site, over three years. We used each quoll’s unique pelage pattern to identify individual quolls and estimate population density at each site. We were able to assign more than 94% of quoll image sequences across both sites to identify 173 individuals during the study. Density estimates of 0.13–0.66 quolls per km² at the fragmented site were comparable to estimates of 0.28–0.48 quolls per km² at the intact site. Our results highlight the importance of retaining and protecting forest fragments for the conservation of endangered quoll populations.

Ecology, occurrence and distribution of wild felids in Sarawak, Malaysian Borneo

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.

Density and occupancy of leopard cats across different forest types in Cambodia

The leopard cat (Prionailurus bengalensis) is the most common wild felid in Southeast Asia, yet little is known about the factors that affect their population density and occupancy in natural habitats. Although leopard cats are highly adaptable and reportedly can attain high densities in human-modified habitats, it is not clear which natural habitat is optimal for the species. Also, this felid has been preyed upon by large carnivores in Southeast Asia, yet the intra-guild effects of large carnivore presence on leopard cats are almost unknown. To shed light on these fundamental questions, we used data from camera trap surveys for felids to determine the leopard cat densities in three different forest types within Cambodia: continuous evergreen, mosaic dominated by evergreen (hereafter evergreen mosaic), and mosaic dominated by open dry deciduous forests (hereafter DDF mosaic). We also conducted occupancy analyses to evaluate the interactions of the leopard cats with three large carnivores: leopards (Panthera pardus), dholes (Cuon alpinus), and domestic dogs (Canis familiaris). The estimated density (individuals/100 km2 ± SE) was highest in the continuous evergreen (27.83 ± 7.68), followed by evergreen mosaic (22.06 ± 5.35) and DDF mosaic (13.53 ± 3.23). Densities in all three forest types were relatively high compared to previous studies. Domestic dogs were detected on all 3 sites, and leopards and dholes had sufficient records on only one site each. The occupancy probability of leopard cats was not affected by the presence or absence of any large carnivore, indicating that large carnivores and leopard cats occurred independently of each other. Our findings support the claim that leopard cats are habitat generalists, but we show that evergreen forest is the optimum natural habitat for this species in the region. The DDF mosaic appears to sustain lower densities of leopard cats, probably due to the harsh dry season and wildfires that led to reduced prey base, although this generalist felid was still able to occupy DDF in relatively moderate numbers. Overall, the adaptability of leopard cats to various forest types, and lack of negative interaction with large carnivores, helps to explain why this species is the most common and widespread felid in Southeast Asia.

The ecology of the banded civet ( Hemigalus derbyanus ) in Southeast Asia with implications for mesopredator release, zoonotic diseases, and conservation

Habitat loss and degradation threaten forest specialist wildlife species, but some generalist mesopredators exploit disturbed areas and human‐derived food, which brings them into closer contact with humans. Mesopredator release is also important for human health for known zoonotic disease reservoirs, such as Asian civets (Viverridae family), since this group includes the intermediator species for the SARS‐CoV‐1 outbreak. Here we use camera trapping to evaluate the habitat associations of the widespread banded civet (Hemigalus derbyanus) across its range in Southeast Asia. At the regional scale, banded civet detections among published studies were positively associated with forest cover and negatively associated with human population. At the local scale (within a landscape), hierarchical modeling of new camera trapping showed that abundance was negatively associated with forest loss and positively associated with distance to rivers. These results do not support mesopredator release and suggest a low likelihood overlap with humans in degraded habitats and, therefore, a low risk of zoonotic disease transmission from this species in the wild. We also estimate that banded civet distribution has contracted to under 21% of its currently recognized IUCN Red List range, only 12% of which falls within protected areas, and a precipitous recent decline in population size. Accordingly, we suggest the banded civet's Red List status should be re‐evaluated in light of our findings.

The Winner Takes it All: Risk Factors and Bayesian Modelling of the Probability of Success in Escaping from Big Cat Predation

Simple Summary

Predation is a complex behavioural interaction that is conditioned by biotic and abiotic factors. In their struggle for survival, the agents participating in the hunt interaction adapt their strategies seeking an opposite interest which leads to the same outcome, success in surviving. Predator/prey interaction data was obtained from on-line posted videos. The examination of records suggested that the species and age range of the predator, its status at the end of the hunt, the time elapsed between the sighting of its prey and the physical contact with it, the species of the prey and the relief of the land were determined success of escape of the prey in case of attack. The present study sheds light on the multietiological nature of predatory abilities and the strategies to fend off anti-predation strategies of the prey in big cats. The theoretical and empirical contents derived from this work will allow the design of environmental enrichment programs in captivity to be substantially improved by providing preys and enough space for them to express big cats predating strategies. The extrapolation of these results to domestic contexts may enable approaching selection strategies from two perspectives, with the aim to boost predating ability of domestic felids for pest control or to enhance defence in domestic ruminant prey from big cats.

Abstract

The individuals engaged in predation interactions modify their adaptation strategies to improve their efficiency to reach success in the fight for survival. This success is linked to either capturing prey (predator) or escaping (prey). Based on the graphic material available on digital platforms both of public and private access, this research aimed to evaluate the influence of those animal- and environment-dependent factors affecting the probability of successful escape of prey species in case of attack by big cats. Bayesian predictive analysis was performed to evaluate the outcomes derived from such factor combinations on the probability of successful escape. Predator species, age, status at the end of the hunting act, time lapse between first attention towards potential prey and first physical contact, prey species and the relief of the terrain, significantly conditioned (p < 0.05) escape success. Social cooperation in hunting may be more important in certain settings and for certain prey species than others. The most parsimonious model explained 36.5% of the variability in escaping success. These results can be useful to design translatable selective strategies not only seeking to boost predation abilities of domestic felids for pest control, but also, biological antipredator defence in potential domestic prey of big cats.

Crop protection practices and viral zoonotic risks within a One Health framework

Recent viral zoonotic epidemics have been attributed partially to the negative impact of human activities on ecosystem biodiversity. Agricultural activities, particularly conventional crop protection (CP) practices, are a major threat to global biodiversity, ecosystem health and human health. Here we review interactions between CP practices and viral zoonoses (VZs), the first time this has been done. It should be noted that a) VZs stand at the interface between human, animal and ecosystem health; b) some VZs involve arthropod vectors that are affected by CP practices; and c) some crop pests, or their natural enemies are vertebrate reservoirs/carriers of certain VZs, and their contact with humans or domestic animals is affected by CP practices. Our review encompasses examples highlighting interactions between VZs and CP practices, both efficiency improvement-based (i.e. conventional with agrochemical insecticides and rodenticides), substitution-based (i.e. mainly with physical/mechanical or biopesticidal pest control), and redesign-based (i.e. mainly with conservation biological pest control, including some forms of crop-livestock integration). These CP practices mainly target arthropod and vertebrate pests. They also target, to a lesser extent, weeds and plant pathogens. Conventional and some physical/mechanical control methods and some forms of biopesticidal and crop-livestock integration practices were found to have mixed outcomes in terms of VZ risk management. Conversely, practices based on biological control by habitat conservation of arthropod or vertebrate natural enemies, falling within the Agroecological Crop Protection (ACP) framework, result in VZ prevention at various scales (local to global, and short-term to long-term). ACP addresses major global challenges including climate resilience, biodiversity conservation and animal welfare, and helps integrate plant health within the extended "One Health" concept.

Diet, prey selection, and activity of Asian golden cats and leopard cats in northern Laos

The Asian golden cat (Catopuma temminckii) occurs in small, declining, and highly fragmented populations throughout Southeast Asia, whereas the smaller leopard cat (Prionailurus bengalensis) is common and widespread. In contrast to leopard cats, little is known about the ecology of Asian golden cats, and resource partitioning between these species has not been studied. We used DNA-confirmed scats, camera-trap data, and prey surveys, to determine the diet, prey selection, and activity, of Asian golden cats and leopard cats in a protected area in northern Laos. The two felids had different diets: Asian golden cats consumed mostly ungulates (35% biomass consumed), murid rodents (23%), and carnivores (15%), whereas leopard cats consumed mostly murid rodents (79%). Asian golden cats were not random in their consumption of ungulates, because muntjac (Muntiacus spp.) were selectively consumed over larger ungulates, indicating muntjac were preyed upon rather than scavenged. Dietary overlap between the two felid species was moderate (R0 = 0.60), and the dietary niche breadth of Asian golden cats (B = 8.44) was nearly twice as high as that of leopard cats (4.54). The mean (± SD) scat diameter was greater for Asian golden cats (2.1 ± 0.3 cm) than leopard cats (1.8 ± 0.2 cm), although diameters of leopard cat scats were considerably larger than previously assumed for this species. The felid species differed in their activity patterns, because Asian golden cats were diurnal, whereas leopard cats were nocturnal, although they did not differ in their use of elevation, suggesting there was no habitat segregation. Overall, leopard cats appeared to coexist with Asian golden cats, a potential predator and competitor, by exhibiting dietary and temporal partitioning. Our results showed that muntjac were important prey of Asian golden cats, suggesting the management of muntjac might be important for conserving populations of Asian golden cats.

The influence of human disturbance on wildlife nocturnality

Rapid expansion of human activity has driven well-documented shifts in the spatial distribution of wildlife, but the cumulative effect of human disturbance on the temporal dynamics of animals has not been quantified. We examined anthropogenic effects on mammal diel activity patterns, conducting a meta-analysis of 76 studies of 62 species from six continents. Our global study revealed a strong effect of humans on daily patterns of wildlife activity. Animals increased their nocturnality by an average factor of 1.36 in response to human disturbance. This finding was consistent across continents, habitats, taxa, and human activities. As the global human footprint expands, temporal avoidance of humans may facilitate human-wildlife coexistence. However, such responses can result in marked shifts away from natural patterns of activity, with consequences for fitness, population persistence, community interactions, and evolution.

Spatio-temporal ecology of sympatric felids on Borneo. Evidence for resource partitioning?

Niche differentiation, the partitioning of resources along one or more axes of a species' niche hyper-volume, is widely recognised as an important mechanism for sympatric species to reduce interspecific competition and predation risk, and thus facilitate co-existence. Resource partitioning may be facilitated by behavioural differentiation along three main niche dimensions: habitat, food and time. In this study, we investigate the extent to which these mechanisms can explain the coexistence of an assemblage of five sympatric felids in Borneo. Using multi-scale logistic regression, we show that Bornean felids exhibit differences in both their broad and fine-scale habitat use. We calculate temporal activity patterns and overlap between these species, and present evidence for temporal separation within this felid guild. Lastly, we conducted an all-subsets logistic regression to predict the occurrence of each felid species as a function of the co-occurrence of a large number of other species and showed that Bornean felids co-occurred with a range of other species, some of which could be candidate prey. Our study reveals apparent resource partitioning within the Bornean felid assemblage, operating along all three niche dimension axes. These results provide new insights into the ecology of these species and the broader community in which they live and also provide important information for conservation planning for this guild of predators.