Using camera trapping and hierarchical occupancy modelling to evaluate the spatial ecology of an African mammal community

Abstract

1. Emerging conservation paradigms have shifted from single to multi-species approaches focused on sustaining biodiversity. Multi-species hierarchical occupancy modelling provides a method for assessing biodiversity while accounting for multiple sources of uncertainty. 2. We analysed camera trapping data with multi-species models using a Bayesian approach to estimate the distributions of a terrestrial mammal community in northern Botswana and evaluate community, group, and species-specific responses to human disturbance and environmental variables. Groupings were based on two life-history traits: body size (small, medium, large and extra-large) and diet (carnivore, omnivore and herbivore). 3. We photographed 44 species of mammals over 6607 trap nights. Camera station-specific estimates of species richness ranged from 8 to 27 unique species, and species had a mean occurrence probability of 0Á32 (95% credible interval = 0Á21-0Á45). At the community level, our model revealed species richness was generally greatest in floodplains and grasslands and with increasing distances into protected wildlife areas. 4. Variation among species' responses was explained in part by our species groupings. The positive influence of protected areas was strongest for extra-large species and herbivores, while medium-sized species actually increased in the non-protected areas. The positive effect of grassland/ floodplain cover, alternatively, was strongest for large species and carnivores and weakest for small species and herbivores, suggesting herbivore diversity is promoted by habitat heterogeneity. 5. Synthesis and applications. Our results highlight the importance of protected areas and grasslands in maintaining biodiversity in southern Africa. We demonstrate the utility of hierarchical Bayesian models for assessing community, group and individual species' responses to anthropogenic and environmental variables. This framework can be used to map areas of high conservation value and predict impacts of land-use change. Our approach is particularly applicable to the growing number of camera trap studies world-wide, and we suggest broader application globally will likely result in reduced costs, improved efficiency and increased knowledge of wildlife communities.

Carnivore distributions in Botswana are shaped by resource availability and intraguild species

“…Among the resources included, mopane cover had the largest influence on species’ distributions where species were generally less likely to occupy areas dominated by mopane shrub and woodlands. This is consistent with previous studies reporting greater biodiversity of African mammals in grassland savannas (Oindo & Skidmore, ; Rich et al ., ). In contrast with previous studies (Pettorelli et al ., ; Schuette et al ., ), we found no evidence that permanent water was a significant predictor of carnivore distributions.…”

Logging and indigenous hunting impacts on persistence of large Neotropical animals

“…, Rich et al . ). Our model represents a multi‐species approach to obtain composite information by estimating occurrence probabilities for each species (Dorazio & Royle ).…”

Assessing global patterns in mammalian carnivore occupancy and richness by integrating local camera trap surveys

“…We analysed the two study areas in Argentina separately because they were independent studies carried out in vastly different ecosystems. In Africa, studies were located in the Cederberg mountains of Western Cape, South Africa (Martins, ), Ngamiland District of northern Botswana (Rich et al, ), Niokolo Koba National Park of Senegal (Kane, Morin, & Kelly, ) and the Masoala‐Makira protected landscape of Madagascar (Farris et al, ). In Asia, we included studies from the southern Riau landscape of central Sumatra in Indonesia (Sunarto, Kelly, Parakkasi, & Hutajulu, ), the Churia habitat in Chitwan National Park in the south‐central Terai Arc in Nepal (Thapa & Kelly, ) and seven reserves across central Iran (Farhadinia et al, ).…”