Multi-species Occupancy Model Research Articles

Landscape Structure and Seasonality: Effects on Wildlife Species Richness and Occupancy in a Fragmented Dry Forest in Coastal Ecuador

Despite high fragmentation and deforestation, little is known about wildlife species richness and occurrence probabilities in tropical dry forest (TDF) landscapes. To fill this gap in knowledge, we used a Sentinel-2-derived land-cover map, Normalized Difference Vegetation Index (NDVI) data and a multi-species occupancy model to correct for detectability to assess the effect of landscape characteristics on medium and large mammal occurrence and richness in three TDF areas that differ in disturbance and seasonality in Ecuador. We recorded 15 species of medium and large mammals, distributed in 12 families; 1 species is critically Endangered, and 2 are Near-Threatened. The results indicate that species occupancy is related to low forest cover and high vegetation seasonality (i.e., high difference in NDVI between the wet and dry seasons). We believe that the apparent negative effect of forest cover is an indicator of species tolerance for disturbance. The three sampling areas varied from 98% to 40% forest cover, yet species richness and occupancy were not significantly different among them. Vegetation seasonality indicates that more seasonal forests (i.e., those where most tree species lose their leaves during the dry season) tend to have higher mammal species occupancy compared to less seasonal, semi-deciduous forests. Overall, occupancy did not vary between the dry and wet seasons, but species-specific data indicate that some species exhibit higher occupancy during the wet season. This research offers a good understanding of mammal species’ responses to habitat disturbance and fragmentation in TDFs and provides insights to promote their conservation.

Bird occupancy in intensively managed agroecosystems under large-scale organic and conventional farming in Argentina: A multi-species approach

Several studies in European and North American agroecosystems conclude that organic farming benefits birds compared to conventional farming. Nevertheless, there are some biases toward these geographic regions and farm size. Argentinian agroecosystems are particularly homogeneous with large arable fields and sparse uncultivated field margins (i.e. large-scale homogenous cropping systems). In Argentina only 0.55% of the total farmland is under organic farming. Thus, our aims were to assess differences in bird occupancy between organic versus conventional farming regimes, and whether bird occupancy varied in relation to annual crop proportion in both farming regimes in central Argentina agroecosystems. We surveyed 156 points in farms under conventional and 154 in organic farming regimes during two bird-breeding seasons. We used multi-species occupancy models with a Bayesian approach to estimate bird occupancy. We observed that the type of farming regime (organic in relation to conventional) had a weak effect on avian occupancy, varying by species and groups. Probability of occupancy was higher for a few insectivorous and omnivorous species but lower for carnivores in organic farms in relation to conventional ones. The proportion of annual crops was positively correlated with occupancy of an insectivore aerial forager, some insectivore foliage gleaners, a granivore, and some omnivorous species in organic farms, but not conventional farms. This work contributes to reducing geographic and small-scale heterogeneous cropping system biases in the avian agroecological literature. Our results, together with future studies needed to assess landscape configuration and composition, and resource availability for birds in each farming regime, will allow the evaluation of organic farming as a tool for the conservation of bird species in large-scale homogeneous cropping systems in temperate regions.

Determining Community-level Carnivore Response to Landscape Factors in Bukit Barisan Selatan National Park, Sumatra, Indonesia.

Researchers are challenged to understand the distribution of biodiversity on the landscape or determine if community-level assemblages respond to landscape variability. Canonical ordinations and multispecies occupancy modeling are often utilized and differ in their analytical scale and technique. Community-level data for carnivores (n=18) from camera trapping data (n=60) were tested for their collective response to covariates (distance to villages, roads, plantations, streams, and also topographic variables for elevation and slope) in Bukit Barsan Selatan National Park. Redundancy analysis (RDA) results confirmed that the carnivore community responded to the anthropogenic covariates, with carnivore detections being higher in areas at a high distance from roads and plantations medium distance villages. Then, multispecies occupancy models (MSOM), a comparatively finer temporal scale analysis that incorporated imperfect detections, were compared to RDA. We fit four models (full, anthropogenic, natural, and null) that were mainly inconclusive. In some MSOM models, the carnivore community did respond to environmental covariates, although the coefficients did not show a consistent response between seasons or years. These results indicate that RDA was able to detect broad-scale covariate effects that were not able to be modeled by MSOM and that these scaling and imperfect detection issues should be considered when attempting to understand landscape community diversity.

Amphibian population responses to mitigation: Relative importance of wetland age and design

Wetland creation is a common practice to mitigate for the loss of natural wetlands. However, there is still uncertainty about how effectively created wetlands replace habitat provided by natural wetlands. This uncertainty is due in part because post-construction monitoring of biological communities, and vertebrates especially, is rare and typically short-term (<5 years). We estimated occupancy of 4 amphibian species in 8 created mitigation wetlands, 7 impacted wetlands, and 7 reference wetlands in the Greater Yellowstone Ecosystem in Wyoming, USA. Mitigation wetlands were created to replace wetland habitat that was lost during road construction and ranged in age from 1 to 10 years when sampled. Impacted wetlands were natural wetlands partially filled by road construction and were adjacent to a highway. We sampled for amphibian larvae during 6 summers from 2013 to 2020 and used multi-species occupancy models that estimated detection and occupancy of each of 4 amphibian species to determine how amphibian responses changed over time, especially in mitigation wetlands. Occupancy did not differ between impacted and reference wetlands for any of the 4 amphibian species. Western Toads (Anaxyrus boreas) were most common (although briefly) in created wetlands, and occupancy of Columbia Spotted Frogs (Rana luteiventris), Western Tiger Salamanders (Ambystoma mavortium), and Boreal Chorus Frogs (Pseudacris maculata) was lower in created wetlands than in impacted or reference wetlands. Individual wetland area was positively associated with occupancy for all 4 species and wetland vegetation cover was positively associated with Boreal Chorus Frog and Columbia Spotted Frog occupancy; these results emphasize the importance of design characteristics when planning mitigation wetlands. The link between wetland age and occupancy was complex and included threshold and quadratic relationships for three of the four species, but only Boreal Chorus Frog occupancy was still increasing slowly at the end of our study. Our results indicate created wetlands did not attain the suitability of impacted and natural wetlands for local amphibians, even several years after construction. The complex relationships between wetland age and species-specific occupancy illustrate the importance of long-term monitoring in describing population responses to the construction of wetlands as mitigation for wetland loss.

Marginal support for a trophic cascade among sympatric canids in peripheral wolf range.

Trophic cascades reportedly structure ecological communities through indirect species interactions. Though the predator-herbivore-autotroph relationship has received much attention, mechanistic evidence supporting intraguild trophic cascades is rare. We established 348 remote camera sites (1 August-5 September 2019) across seven study areas of varying wolf (Canis lupus) density including one study area where wolves were absent in northern Michigan, USA. Using multi-species occupancy modeling at species-relevant spatial scales, we evaluated the hypothesis that increased wolf occurrence suppresses coyote (C. latrans) occurrence with corresponding increased red fox (Vulpes vulpes) occurrence mediated by land cover edge density, human presence, and temporal partitioning. Remote cameras recorded >600,000 images and included 6,370, 10,137, and 4,876 detections of wolves, coyotes, and foxes, respectively. Fox occupancy probability was more than three times as high (0.29) at camera sites where wolves were present, relative to sites wolves were absent (0.09). Pairwise species interactions supported expected size-based dominance patterns among canids and insignificant effects were directionally consistent with reported reduced strength of top-down effects in peripheral wolf range. Increased edge density also increased co-occurrence of coyote and wolves, likely a function of increased prey availability and refugia for coyotes. Though foxes occurred in spatial proximity to wolves, competition was limited by greater temporal partitioning than observed between coyotes and foxes that were spatially segregated. Collectively, our results provide marginal support for the reported trophic cascade among wolves, coyotes, and foxes wherein top-down effects may be reduced near the edge of current wolf distributions. As predators continue to recolonize portions of their historic range, knowledge of the effects on intraguild predators has implications for species management and predicting prey population responses.

Intermediate fire severity diversity promotes richness of forest carnivores in California

AbstractAimFire can strongly influence ecosystem function, and human activities are disrupting fire activity at the global scale. Ecological theory and a growing body of literature suggest that a mixed severity fire regime promotes biodiversity in western North America. Some researchers advocate the use of pyrodiversity (i.e. heterogeneity in aspects of the fire regime such as time since fire or severity) as a conservation index to be maximized. Others caution against this approach arguing that the index oversimplifies fire–biodiversity interactions across trophic, spatial and temporal scales. We evaluated the effects of several landscape‐scale pyrodiversity indices, and their severity and time‐since‐fire components, on species richness of forest carnivores.LocationNorthern California, United States.MethodsWe gathered data on fire history and mammal occurrence from camera trap surveys at 1,451 sites across Northern California public and private forestlands during 2009–2018. We used these data to model the effects of fire severity diversity, and its components (i.e. low, moderate and high severity wildfires), on carnivore richness at short (10 years) and longer (25 years) timeframes. We repeated the modelling using a measure of time‐since‐fire diversity and its components (&lt;10 years, 10–20 years, 20–30 years, 30–40 years, 40–100 years). We used Bayesian multispecies occupancy modelling to correct for imperfect measurement of species richness.ResultsWe found that carnivore richness was highest at locations with intermediate fire severity diversity (0.46, 90%CI: 0.40–0.52) calculated using Simpson's Measure of Evenness (range: 0–1) for the 10‐year timeframe, and the results were almost identical yet less precise for the longer timeframe. When we separated fire severity diversity into its components, we found that carnivore richness was highest at locations where 17% (90%CI: 4–20) of the landscape had experienced low severity burns over the past decade. In contrast, we found no association between time‐since‐fire diversity and carnivore richness, however, an intermediate amount of one of the components (e.g., the total amount of fire in the past 10 years) was positively associated with carnivore richness. Our results are consistent with a mixed severity fire regime wherein there is a greater extent of low severity than high severity fire.Main conclusionsOverall our results suggest that carnivores would benefit from landscapes managed for greater, but not maximal, fire severity diversity. Our results also suggest that prescribed, low severity burns may provide ecological services to wildlife not otherwise provided by silviculture in a managed forest landscape.

Living in the concrete jungle: carnivore spatial ecology in urban parks.

People and wildlife are living in an increasingly urban world, replete with unprecedented human densities, sprawling built environments, and altered landscapes. Such anthropogenic pressures can affect multiple processes within an ecological community, from spatial patterns to interspecific interactions. We tested two competing hypotheses, human shields vs. human competitors, to characterize how humans affect the carnivore community using multispecies occupancy models. From 2017 to 2020, we conducted the first camera survey of city parks in Detroit, Michigan, and collected spatial occurrence data of the local native carnivore community. Our 12,106–trap night survey captured detection data for coyotes (Canis latrans), red foxes (Vulpes vulpes), raccoons (Procyon lotor), and striped skunks (Mephitis mephitis). Overall occupancy varied across species (Ψcoyote = 0.40, Ψraccoon = 0.54, Ψred fox = 0.19, Ψstriped skunk = 0.09). Contrary to expectations, humans did not significantly affect individual occupancy for these urban carnivores. However, co‐occurrence between coyote and skunk increased with human activity. The observed positive spatial association between an apex and subordinate pair supports the human shield hypothesis. Our findings demonstrate how urban carnivores can exploit spatial refugia and coexist with humans in the cityscape.

Multi‐Species Occupancy Modeling Provides Novel Insights into Amphibian Metacommunity Structure and Wetland Restoration

A fundamental goal of community ecology is to understand species-habitat relationships and how they shape metacommunity structure. Recent advances in occupancy modeling enable habitat relationships to be assessed for both common and rare species within metacommunities using multi-species occupancy models (MSOM). These models account for imperfect species detection and offer considerable advantages over other analytical tools commonly used for community analyses under the elements of metacommunity structure (EMS) framework. Here, we demonstrate that MSOM can be used to infer habitat relationships and test metacommunity theory, using amphibians. Repeated frog surveys were undertaken at 55 wetland sites in southeastern Australia. We detected 11 frog species from three families (Limnodynastidae, Myobatrachidae, and Pelodryadidae). The rarest species was detected at only one site whereas the most common species was detected at 42 sites (naive occupancy rate 0.02-0.76). Two models were assessed representing two competing hypotheses; the best-supported model included the covariates distance to the nearest site (connectivity), wetland area, presence of the non-native eastern mosquitofish (Gambusia holbrooki), proportion cover of emergent vegetation, an interaction term between Gambusia and emergent vegetation cover, and the proportion canopy cover over a site. Hydroperiod played no detectable role in metacommunity structure. We found species-habitat relationships that fit with current metacommunity theory: occupancy increased with wetland area and connectivity. There was a strong negative relationship between occupancy and the presence of predatory Gambusia, and a positive interaction between Gambusia and emergent vegetation. The presence of canopy cover strongly increased occupancy for several tree frog species, highlighting the importance of terrestrial habitat for amphibian community structure. We demonstrated how responses by amphibians to environmental covariates at the species level can be linked to occupancy patterns at the metacommunity scale. Our results have clear management implications: wetland restoration projects for amphibians and likely other taxa should maximize wetland area and connectivity, establish partial canopy cover, and eradicate Gambusia or provide aquatic vegetation to mitigate the impact of this non-native fish. We strongly advocate the use of MSOM to elucidate the habitat drivers behind animal occupancy patterns and to derive unbiased occupancy estimates for monitoring programs.

Effects of rice-field abandonment rates on bird communities in mixed farmland–woodland landscapes in Japan

Farmland abandonment can be a significant driver of biodiversity change in many parts of the world. Knowledge of the ecological impact of farmland abandonment at the landscape scale is particularly limited in Asia. We investigated how rice-field abandonment impacts bird diversity (i.e., species richness and composition) during the breeding and wintering seasons. Birds were surveyed in 31 grids (1 × 1 km) in rice ecosystems in central Japan, 16 of which were dominated by farmland while the others were surrounded by woodland. In each landscape type, survey grids were selected to ensure a broad range of abandonment rates, from fully cultivated to largely abandoned sites. Multi-species occupancy models showed that occupancy probabilities were associated with linear and quadratic terms of the abandonment rate, resulting in the highest predicted community-level occupancies and species richness at moderate abandonment rates (51.5–71%, depending on the season and surrounding landscapes, with the highest percentage in woodland landscapes in winter). Community composition was most associated with surrounding landscapes (i.e., woodland or farmland), followed by the abandonment rate. These results indicate the importance of habitat heterogeneity, related to moderate levels of farmland abandonment, in enhancing bird diversity in both farmland and woodland landscapes. Our findings illustrate the necessity for quantitative measures of farmland abandonment at landscape scales for understanding their nonlinear effects on farmland biodiversity. We suggest that agri-environmental schemes should consider the benefits of enhancing farmland mosaics at landscape scales, especially for small-scale farming in areas where farmland abandonment is increasing.

Mammal responses to reduced-impact logging in Amazonian forest concessions

Production forests are a dominant feature of most tropical forest landscapes and it is therefore important to understand the effects of timber extraction on the resident fauna. Here we investigate the effects of reduced-impact logging (RIL) on medium- to large-sized terrestrial mammals in two Jamari National Forest logging concessions, south-western Brazilian Amazonia. We used camera traps to survey the terrestrial mammal fauna. Bayesian multi-species occupancy models (MSOMs) were performed to assess the effect of logging intensity and density of logging roads on site-level species richness, occupancy and detection rates. Species richness was negatively affected by logging status and by increasing logging intensity, and positively affected by road density. Occupancy and detection rates of individual species were largely unrelated to model predictors, although responses across species tended to be consistent with that observed for species richness. Despite negative effects of logging on species richness, no individual species were lost at the landscape level, suggesting that concessions managed under RIL techniques may be a reasonable compromise between economic and conservation interests.

Multi-species occupancy modeling provides novel insights into amphibian metacommunity structure and wetland restoration.

A fundamental goal of community ecology is to understand species-habitat relationships and how they shape metacommunity structure. Recent advances in occupancy modeling enable habitat relationships to be assessed for both common and rare species within metacommunities using multi-species occupancy models (MSOM). These models account for imperfect species detection and offer considerable advantages over other analytical tools commonly used for community analyses under the elements of metacommunity structure (EMS) framework. Here, we demonstrate that MSOM can be used to infer habitat relationships and test metacommunity theory, using amphibians. Repeated frog surveys were undertaken at 55 wetland sites in southeastern Australia. We detected 11 frog species from three families (Limnodynastidae, Myobatrachidae, and Pelodryadidae). The rarest species was detected at only one site whereas the most common species was detected at 42 sites (naive occupancy rate 0.02-0.76). Two models were assessed representing two competing hypotheses; the best-supported model included the covariates distance to the nearest site (connectivity), wetland area, presence of the non-native eastern mosquitofish (Gambusia holbrooki), proportion cover of emergent vegetation, an interaction term between Gambusia and emergent vegetation cover, and the proportion canopy cover over a site. Hydroperiod played no detectable role in metacommunity structure. We found species-habitat relationships that fit with current metacommunity theory: occupancy increased with wetland area and connectivity. There was a strong negative relationship between occupancy and the presence of predatory Gambusia, and a positive interaction between Gambusia and emergent vegetation. The presence of canopy cover strongly increased occupancy for several tree frog species, highlighting the importance of terrestrial habitat for amphibian community structure. We demonstrated how responses by amphibians to environmental covariates at the species level can be linked to occupancy patterns at the metacommunity scale. Our results have clear management implications: wetland restoration projects for amphibians and likely other taxa should maximize wetland area and connectivity, establish partial canopy cover, and eradicate Gambusia or provide aquatic vegetation to mitigate the impact of this non-native fish. We strongly advocate the use of MSOM to elucidate the habitat drivers behind animal occupancy patterns and to derive unbiased occupancy estimates for monitoring programs.

The influence of species life history and distribution characteristics on species responses to habitat fragmentation in an urban landscape.

Fragmentation within urbanized environments often leads to a loss of native species diversity; however, variation exists in responses among-species and among-populations within species. We aimed to identify patterns in species biogeography in an urbanized landscape to understand anthropogenic effects on vertebrate communities and identify species that are more sensitive or resilient to landscape change. We investigated patterns in species richness and species responses to fragmentation in southern Californian small vertebrate communities using multispecies occupancy models and determined factors associated with overall commonness and sensitivity to patch size for 45 small vertebrate species both among and within remaining non-developed patches. In general, smaller patches had fewer species, with amphibian species richness being particularly sensitive to patch size effects. Mammals were generally more common, occurring both in a greater proportion of patches and a higher proportion of the sites within occupied patches. Alternatively, amphibians were generally restricted to larger patches but were more ubiquitous within smaller patches when occupied. Species range size was positively correlated with how common a species was across and within patches, even when controlling for only patches that fell within a species' range. We found sensitivity to patch size was greater for more fecund species and depended on where the patch occurred within a species' range. While all taxa were more likely to occur in patches in the warmer portions of their ranges, amphibians and mammals were more sensitive to fragmentation in these warmer areas as compared to the rest of their ranges. Similarly, amphibians occurred at a smaller proportion of sites within patches in drier portions of their ranges. Mammals occurred at a higher proportion of sites that were also in drier portions of their range while reptiles did not differ in their sensitivity to patch size by range position. We demonstrate that taxonomy, life history, range size and range position can predict commonness and sensitivity of species across this highly fragmented yet biodiverse landscape. The impacts of fragmentation on species communities within an urban landscape depend on scale, with differences emerging among and within species and populations.

Assessing mammal species richness and occupancy in a Northeast Asian temperate forest shared by cattle

AbstractAimAsian forests are becoming increasingly degraded and fragmented by the extensive intensification of anthropogenic activities; these activities threaten wildlife and ecosystem sustainability. Facing a defaunation crisis, managers need more information on species assemblages to guide conservation efforts. We tested the relative influence of natural and anthropogenic factors on mammalian species richness and occupancy in temperate forests in Northeast Asia.LocationNortheast China.MethodsCamera‐trapping data and multispecies occupancy models were used to estimate the species richness of a terrestrial mammal community in a working landscape and assess community‐, group‐, and species‐specific responses to natural and anthropogenic features while accounting for imperfect detection. Species were grouped based on body size, diet and activity pattern.ResultsWe deployed 138 cameras and photographed 21 mammalian species over 22,976 trap days across the China–Russia border. Both natural and anthropogenic correlates varied in their importance in predicting the presence of different animals. Vegetation cover and cattle were found to have significantly positive and negative influences on community‐level mammalian occupancy, respectively. The positive relationship with vegetation cover was most evident for large or diurnal species; the negative relationship with cattle was most evident for diurnal and wild ungulate species. Large species occupancy was also negatively associated with human settlements. The predicted richness across each station varied from 5 to 14 unique species, and species had a mean occupancy probability of 0.45 (95% credible interval = 0.09–0.86). Species richness was generally the lowest in livestock grazing areas and close to human settlements. Human influence is more important than the influences of vegetation and environmental variables.Main conclusionsOur results highlight that livestock grazing was the primary human disturbance that had a negative impact on species occupancy and richness. Multispecies occupancy models helped to identify drivers of biodiversity declines and will inform conservation strategies in human‐dominated landscapes in Northeast Asian forests. We suggest that landscape conservation planning seeks to maximize forest protection and ecosystem services such as biodiversity and carbon storage.

Amphibian responses to conventional and reduced impact logging

Unsustainable timber management, primarily via Conventional selective Logging (CL), has resulted in severe habitat degradation and biodiversity loss. Sustainable techniques, principally Reduced Impact Logging (RIL), are therefore essential for conserving highly threatened, physiologically sensitive taxa such as amphibians. In this study we compare the effects of CL and RIL on stream amphibians across a regeneration gradient in two forest reserves in Sabah, Malaysian Borneo. We analysed data from a community of stream amphibians across 29 transects subject to either CL (18 – 21 years since logging) or RIL (4 – 21). Multi-species occupancy modelling determined community and species responses to logging types, regeneration times and logging associated environmental factors. Diversity profiles, which capture representative diversity indices whilst accounting for community evenness, were calculated using occupancy model results. Our results indicated that several species and community occupancy generally responded negatively to logging associated covariates (lower aboveground carbon density and higher siltation). Stream breeding species occupancy was generally lower in CL compared to RIL sites, with higher generalist breeding species occupancy in CL sites. Diversity profiles identified higher anuran diversity and evenness in RIL compared to CL sites of the same age (18 – 21 years). Furthermore, anuran diversity and evenness exhibited a distinct recovery from 4 to 21 years following RIL. Our results provide strong evidence that RIL reduces the negative impacts on stream habitats, amphibian occupancy and diversity compared to CL, and suggest a far quicker recovery after RIL. We believe RIL presents a promising alternative for sustainable tropical timber management and stream amphibian conservation.

Hare today, gone tomorrow: the role of interspecific competition in shaping riverine rabbit occurrence

Effective conservation, particularly of threatened species, requires an understanding of both abiotic and biotic drivers of distribution. In the case of one of Africa’s most endangered mammals, the riverine rabbit Bunolagus monticularis, only environmental covariates of presence have been used to provide coarse predictions of their distribution. Two potential competitors, namely scrub hare Lepus saxatilis and cape hare L. capensis, have significant (&gt;90%) range overlap with the riverine rabbit, yet little is known about how these species interact. We used multi-species occupancy models, which model co-occurrence as a function of environmental variables, to assess the spatial response of riverine rabbits to both species of hare in Sanbona Wildlife Reserve, South Africa. We also examined temporal overlap between riverine rabbits and hares. Camera trapping data were collected from 150 camera traps distributed in clusters of 5 cameras at 30 independent sites, covering 223.24 km2. Contrary to prior studies, we found that riverine rabbits were not restricted to riparian habitat, and that their occurrence was conditional on hare absence and was negatively affected by terrain ruggedness. Whilst hare occurrence was independent of terrain ruggedness, it was negatively affected by rabbit presence. Activity patterns revealed high temporal overlap between hares and rabbits (Δ = 0.828, CI = 0.745-0.940); however, neither species co-occurred at any given site. Our results suggest that conservation management has greatly underestimated the importance of competition with other lagomorphs in understanding riverine rabbit occurrence.

The value of pastoral ranches for wildlife conservation in the Kalahari

Abstract Context Rangelands can play an important role in conservation by providing additional habitat for many threatened species and maintaining global biodiversity. Identifying areas that can integrate both pastoral and conservation activities is important for capturing benefits from wildlife in non-protected areas. Aims To investigate wildlife distribution in a contiguous landscape comprising both pastoral ranches and wildlife-based areas in western Botswana. Methods We deployed motion-activated camera traps to assess mammal richness and occupancy using a multi-species occupancy model. We tested whether environmental factors influenced these parameters in a commercial ranching block in the western Kalahari region of Botswana, and whether species-specific occupancy varied between ranches and neighbouring wildlife management areas. Key results In the ranching block, vegetation, season and distance to wildlife areas influenced species-specific occupancy and species richness, whereas farm type and water availability affected only a few carnivore species. Commercial ranches supported several threatened species such as African wild dog, cheetah and pangolin, and we detected two species, African civet and serval, not previously considered being present in this region. Mammal diversity was similar between ranches and wildlife areas, but species composition varied. Land use affected species-specific occupancy, with many carnivore species occurring close to or in wildlife areas. Conclusions We showed that commercial ranches in the Kalahari are utilised by many mammal species, and these areas may play an important role in the conservation of threatened species. Understanding species-, group- and community-level responses to the impacts of human activities in rangelands is vital as the need for pastoral land increases. Implications We predicted regions of high occurrence of carnivores that can be important for tackling human–wildlife conflict as well as regions with high species diversity that may be useful for increasing integration of conservation endeavours (e.g. eco-tourism) that promote the benefits of wildlife in predominantly livestock regions.

Responses of Polylepis birds to patch and landscape attributes in the High Andes

ABSTRACT Habitat loss and fragmentation can devastate biodiversity, especially at regional and global scales. However, generalizing to individual species is challenging given the wide variety of intrinsic and extrinsic factors that shape species-specific responses – particularly among species that are specialists, generalists, or adapted to naturally patchy landscapes. In this study, we examined how patch and landscape attributes affected bird communities within Polylepis forest ecosystems, which are patchily distributed within landscapes of Puna grasslands and shrublands in the High Andes of Peru (3,300–4,700 m). We surveyed birds in 59 Polylepis patches and 47 sites in the Puna matrix, resulting in 13,210 observations of 88 bird species, including 15 species of conservation concern specialized on Polylepis. Data were analysed using Multi-Species Occupancy-Models (MSOM) and cumulative species-area curves. Species richness was generally greatest at mid-to-low elevations, within small fragments, and in landscapes with comparatively little forest cover; this was especially true for birds associated with the Puna matrix. Consistent with the hypothesis that Polylepis specialists are adapted to naturally patchy landscapes, we found no evidence that Polylepis specialists were sensitive to patch size, though two of nine species were positively related to forest cover within 200 m. Our work shows that small patches of Polylepis have high ecological value and that conservation of species of concern may depend more on retaining at least 10% forest cover within landscapes than on the presence of large patches of Polylepis.

Mountains and traits: environmental heterogeneity and mammal assemblages along an elevational gradient in the Northern Andes

ABSTRACT We assessed the variation of both composition and functional diversity of mammals along an elevation gradient (1600–3600 masl) at the Tabaconas Namballe National Sanctuary (TNNS) in northern Peru. Using a camera-trap design (85 stations, 8,825 camera days, ~ 317 km2), we recorded a total of 33 mammalian species during the dry season of 2016. Species-specific effects of environmental covariates based on multi-species occupancy modeling showed that only elevation had a statistically significant effect on occupancy. Also, a principal coordinate analysis and a distance-based redundancy analysis suggested that the variation in species composition is mainly explained by elevation, and moderately by both the normalized difference vegetation index (NDVI) and the distance to roads. The highlands appear to be dominated by a reduced assembly of species consisting of the montane guinea pig, the Andean fox, and the northern pudu. Functional diversity decreased with elevation, providing evidence that lowland and highland communities are functionally dissimilar. Moreover, land-use is changing rapidly in the areas surrounding the TNNS, suggesting that increased connectivity at the two extremes of the elevational gradient (the highlands and the lowlands) will ensure the long-term viability of terrestrial mammalian populations and, thus, the ecological processes in which they are involved.

Multi‐species occupancy models: an effective and flexible framework for studies of insect communities

Entomological studies often aim to estimate species distribution, community composition, or species‐richness patterns. False absences can, however, bias these estimates and should consequently not be overlooked in insect studies. Multi‐species occupancy models (MSOMs) afford a flexible solution to cover the main topics in ecological entomology while dealing with detectability issues. We sampled Orthoptera communities at 81 mountain grasslands sites in France, using three sampling techniques: sighting, listening, and sweep netting. Five plots were sampled per site. This sampling design allowed MSOMs to be used to estimate richness, occupancy, and detection probabilities while accounting for the effect of covariates. We also used MSOMs to evaluate the efficiency of the survey design and to assess the effects of sampling optimisation. The estimates obtained for altitudinal distribution were reliable, with known species distributions confirming the relevance of MSOMs to model the effects of covariates on Orthoptera communities. The species‐specific detection probability was often less than one and varied with the detection technique used and the grass height, confirming the need to deal with detection issues in orthopteran studies. We estimated an inventory completeness superior to 0.80 for 93% of the sites, and an overall detection probability superior to 0.95 for 52% of the species, suggesting the sampling design was suitable for studying occupancy in Orthoptera communities. We also found that the sweep netting step may be omitted or the number of plots reduced without affecting species detectability or inventory completeness. Those recommendations may help to optimise future sampling strategies.

Application of Multi-Species Occupancy Modeling to assess mammal diversity in northeast Bangladesh

Bangladesh is one of the most densely populated countries on earth with 1033 persons/km2, yet it also harbors a high level of mammal diversity. Unfortunately, general ecological knowledge is limited in many areas of the country, leading to a lack of cohesive conservation initiatives. As a result, the country is quickly losing integral wildlife habitat. Here we assess the presence and community composition of mammal species in Northeastern Bangladesh. Between May 2014 and January 2015 we conducted camera trapping in four Reserve Forests in Northeastern Bangladesh: Atora Hill Reserve Forest (Atora Hill), Patharia Hill Reserve Forest (Patharia Hill), Rajkandi Reserve Forest (Rajkandi), and Tarap Hill Reserve Forest (Tarap Hill); for a combined total of 1283 trap nights across the four reserves. We then used a Multi-Species Occupancy Model (MSOM) to estimate mammal species occupancy, richness, and community composition in Northeastern Bangladesh. We recorded 27 species of mammals, 23 of which were non-domesticated mammals, consisting of six orders and 15 taxonomic families. Our model suggests there are potentially 37 species of mammals occur in the Northeast Bangladesh. MSOM model also suggests occupancy for each species varies in the region from 69 percent for wild boar (Sus scrofa) to 0.1 percent for small Indian Civet (Viverricula indica). Our study provides the baseline for mammal species richness and community composition in Northeastern Bangladesh. Based on our findings we recommend that public-private partnerships, targeted protected areas, and increased capacity of the local people, are integral to facilitate coexistence between humans and wildlife and to aid in the conservation of mammal diversity in Northeastern Bangladesh.