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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.

Baited camera surveys are often used to study white‐tailed deer Odocoileus virginianus populations and inform harvest decisions. Surveys are commonly conducted in late summer or early fall when deer populations are expected to be segregated sexually, whereas hunting seasons typically occur during the breeding season when sexes are likely to be mixed. However, the effects of socio‐sexual shifts in space use on pre‐season camera surveys has not been evaluated. We conducted a baited survey before the hunting season followed by passive camera surveys during the hunting season on three properties in southwestern Georgia, USA. We collected 51 106 images of deer before and during the hunting season from baited and passive cameras. Based on interpolated maps of camera detections, the populations were highly segregated during the September baited surveys. In contrast, subsequent passive camera surveys indicated high overlap of males and females during the breeding months, with males shifting their distribution towards females. Because most management units on private lands are substantially smaller than our camera arrays (typically < 1000 ha), our results suggest that pre‐season surveys may not accurately reflect the population available for harvest during the hunting season. Establishment of cooperative management programs among adjacent landholdings may improve management effectiveness. In addition, managers should anticipate shifts in male distributions during the breeding months and real‐time analytical approaches could be developed with the use of cellular‐based cameras to rapidly alter harvest objectives.

Seasonality drives natural processes, impacting environmental factors like temperature and resource availability, leading to shifts in wildlife communities. The Andean dry forests exhibit a marked seasonality, with a dry and cold season (May–September) and a warm, wet season (October–April). In a year-long remote camera survey in Southern Bolivia, we identified 29 medium to large mammal species, 18 outside their known distribution ranges. While overall species richness remained stable, photographic records varied between seasons. Capture rates, reflecting species richness and abundance, were more influenced by season and habitat. Wet season rates were lower, but higher in all other habitats compared to the mountain bush and grasslands. Rates increased with altitude and distance to hiking trails, but decreased with increasing distance from main roads. Medium to large mammals were more active during the dry season, indicating adjustments in response to seasonal changes. Our results suggest a cumulative impact of various factors beyond mere seasonality, and call for adjustments in global species distributions. Moreover, emphasize the need for biodiversity monitoring in dry forest habitats, particularly regarding responses to environmental shifts and human-induced alterations.

Long-term monitoring is an important component of effective wildlife conservation. However, many methods for estimating density are too costly or difficult to implement over large spatial and temporal extents. Recently developed spatial mark–resight (SMR) models are increasingly being applied as a cost-effective method to estimate density when data include detections of both marked and unmarked individuals. We developed a generalized SMR model that can accommodate long-term camera data and auxiliary telemetry data for improved spatiotemporal inference in monitoring efforts. The model can be applied in two stages, with detection parameters estimated in the first stage using telemetry data and camera detections of instrumented individuals. Density is estimated in the second stage using camera data, with all individuals treated as unmarked. Serial correlation in detection and density parameters is accounted for using time-series models. The two-stage approach reduces computational demands and facilitates the application to large data sets from long-term monitoring initiatives. We applied the model to 3 years (2015–2017) of white-tailed deer (Odocoileus virginianus) data collected in three study areas of the Big Cypress Basin, Florida, USA. In total, 59 females marked with ear tags and fitted with GPS-telemetry collars were detected along with unmarked females on 180 remote cameras. Most of the temporal variation in density was driven by seasonal fluctuations, but one study area exhibited a slight population decline during the monitoring period. Modern technologies such as camera traps provide novel possibilities for long-term monitoring, but the resulting massive data sets, which are subject to unique sources of observation error, have posed analytical challenges. The two-stage spatial mark–resight framework provides a solution with lower computational demands than joint SMR models, allowing for easier implementation in practice. In addition, after detection parameters have been estimated, the model may be used to estimate density even if no synchronous auxiliary information on marked individuals is available, which is often the case in long-term monitoring.

Deep-sea benthic environments can be home to diverse communities of corals and sponges which are important habitat for marine fishes and invertebrates. From 2010 to 2014, underwater camera surveys in the Aleutian Islands were completed with the objective of evaluating potential effects of substrate type, tidal currents, depth, and fishing pressure on distribution, abundance, diversity, and size of structure-forming invertebrate (SFI) communities. The presence of rocky substrates was associated with higher probability of presence, higher density, and taller SFI. Multivariate analyses showed community structure changed over gradients of substrate, tidal currents, and longitude, with sea whips typically occupying deeper depths and mostly unconsolidated substrates, while other corals were largely found in rocky, shallower areas. These patterns were also reflected in co-occurrence analyses indicating sea whips were negatively associated with other SFI taxa. Most SFI occupied areas of swift tidal currents; however, heights of individual SFI decreased with increasing tidal currents. Coral and sponge densities at some sites in this study exceeded densities reported from other global coral and sponge habitats. Identifying the environmental conditions leading to high-density and high-diversity SFI communities is important for management of fisheries and evaluating potential impacts of climate change in benthic marine ecosystems.

Bait is often used to increase wildlife harvest susceptibility, enhance viewing opportunities, and survey wildlife populations. The effects of baiting depend on how bait influences space use and resource selection at multiple spatial scales. Although telemetry studies allow for inferences about resource selection within home ranges (third-order selection), they provide limited information about spatial variation in density, which is the result of second-order selection. Recent advances in spatial capture-recapture (SCR) techniques allow exploration of second- and third-order selection simultaneously using non-invasive methods such as camera traps. Our objectives were to describe how short-term baiting affects white-tailed deer (Odocoileus virginianus) behavior and distribution. We fit SCR models to camera data from baited and unbaited locations in southwestern Georgia to assess the effects of short-term baiting on second- and third-order selection of deer during summer and winter surveys. We found little evidence of second-order selection during late summer or early winter surveys when camera surveys using bait are typically conducted. However, we found evidence for third-order selection, indicating that resource selection within home ranges is affected. Concentrations in space use resulting from baiting may enhance disease transmission, change harvest susceptibility, and potentially bias the outcome of camera surveys using bait.

The status of several small carnivores in Asia remains poorly known because of the lack of rigorous population assessments. The leopard cat Prionailurus bengalensis is one such species assumed to be common and widespread within the Indian subcontinent. We conducted surveys using automated cameras to estimate densities and abundance of leopard cats in and around 4 protected reserves in the Western Ghats of India. A total effort of 16,736 camera-days across a 2,075-km2 area resulted in 65 detections of 43 uniquely identified individuals. We estimated leopard cat densities using closed population spatial capture–recapture models under a Bayesian framework. Estimated density was highest in Bhadra Tiger Reserve at 10.45 (± 3.03 SD)/100 km2 followed by 4.48 (± 1.31 SD)/100 km2 in Biligiri Rangaswamy Temple (BRT) Tiger Reserve. The surveys yielded sparse data from Nagarahole and Bandipur reserves. High local densities in Bhadra and BRT were clustered around secondary, disturbed or partially modified forests and human-use areas. Our results provide information critical to the conservation of leopard cats, emphasizing the importance of maintaining habitat buffers and wildlife-permeable areas around protected reserves. Insights from our study highlight the potential of the Western Ghats landscape to serve as a long-term conservation area for leopard cats. Further, our study demonstrates the utility of spatially explicit capture–recapture methods for estimating populations of leopard cats, and may be applied to other threatened small carnivores that are uniquely identified from their morphological features.

Context Repeated surveys to investigate mammalian assemblages at the landscape level are crucial to understanding how natural ecosystems function and regulate over time. Objectives We assessed mammalian species richness and occupancy changes across selected protected areas (PAs) in northern KwaZulu-Natal in the Maputaland Conservation Unit, South Africa. Methods We collected data using 366 camera traps during 2013–2014 and 2022–2023, consisting of 183 camera trap sites covering four PAs (iSimangaliso Wetland Park, incorporating Eastern Shores, Western Shores, and False Bay PAs, and Tembe Elephant Park) that varied in size, habitat diversity and disturbance levels. Our study assessed whether changes in mammalian species richness and occupancy occur across protected areas in northern KwaZulu-Natal, relative to biotic drivers (habitat and path type) in protected areas over two independent survey cycles using a multi-species occupancy model. We applied the Royle–Nichols multi-session multi-species hierarchical model to estimate species richness and occupancy dynamics of 39 mammalian species for different PAs while accounting for imperfect detection. Results Species richness increased with PA size across both camera trap cycles. Two PAs (False Bay and Western Shores) experienced major declines in estimated species richness compared with the previous study. Mammalian community richness remained relatively stable. Notable shifts in mammal occupancy for eight species and detection for ten species over two survey periods were found, reflecting changes in habitat composition and potential pressures from poaching and human activities. Eight mammalian species showed marked increases in detection, while others, hippopotamus ( Hippopotamus amphibius ) and serval ( Leptailurus serval ), experienced declines. Occupancy pattern shifts were present, with some species increasing in occupancy, particularly in habitats such as grasslands and forests, while cane rats ( Thryonomys swinderianus ) and white rhinoceroses ( Ceratotherium simum ) showed significant declines. Conclusions Our results suggest that habitat composition changes, particularly the expansion or reduction of specific habitats (e.g., grasslands, forests), influenced species occupancy trends, with more generalist species adapting to broader habitat types and specialist species experiencing occupancy reductions based on habitat specificity. Additionally, poaching was widespread in sections near the Western Shores fence line. Management should intensify antipoaching resources in hotspot areas (security and ranger patrols) to reduce illegal hunting within the reserve. Our multi-species, multi-season models revealed the resilience and stability of terrestrial mammals in PAs within the Maputaland Conservation Unit, KwaZulu-Natal. Through a systematic survey approach, we emphasise the value of long-term monitoring for tracking large-scale population trends in this ecologically and economically significant region.

We used southeastern fox squirrels (Sciurus niger) in the southeastern United States as an example of how modern approaches to estimate density coupled with a reevaluation of previous estimates can provide important new insights into the management and conservation of mammals. There are few rigorous density estimates of southeastern fox squirrels, which hinders our ability to manage and conserve their populations. Based on an initial estimate from 1957 of 38 squirrels/km2 and subsequent decreases in estimates of population densities, noted decreases in hunter harvest reports, and anecdotal observations, southeastern fox squirrels are believed to be declining. To assess the extent of this decline, we first estimated the density of a subspecies of southeastern fox squirrel, Sherman's fox squirrel (S. n. shermani), using live trapping and camera trapping and modern analytical approaches for mark–recapture analysis. Then, to compare our densities to previous work, we calculated a standardized effective survey area correction factor for past studies and recalculated their population densities. Once standardized, we found little temporal or geographic variation in densities of southeastern fox squirrels (2.4–8.5 squirrels/km2) spanning nearly 70 years of research. Past densities were substantially lower than initially reported with corrected survey areas, suggesting that densities may have always been naturally low but were incorrectly inflated due to study designs and statistical approaches. Moreover, corrected densities from all studies were correlated with the bounded survey area, suggesting that researches aiming to estimate population densities of southeastern fox squirrels were frequently conducted at scales too small relative to the size of their home ranges. The use of methodological and analytical approaches such as those used in this study may help to avoid misdirected conservation designations or management actions and misuse of conservation funding.

Estimates of abundance are fundamental for the management and conservation of threatened species. The Mahogany Glider (Petaurus gracilis) is an Endangered marsupial endemic to the Wet Tropics of northeastern Australia. Despite its status, there is no reliable estimate of abundance. In this study, we conducted camera trapping surveys for the species and employed a Bayesian integrated species distribution model to derive abundance estimates. Presence–absence data from camera trapping surveys and presence‐only data from historical sighting records were included in the integrated species distribution model. The model estimated median abundance at 6036, 4834 and 2820 individuals for home range estimates of 9, 16 and 25 ha, respectively. We suggest using the more conservative abundance estimate of about 2800 individuals, based on the 25 ha home range, because it likely best summarizes density across the distribution. Using simulated data, we tested the effects of camera placement and subsampling, demonstrating that clustered camera arrangements and subsampling from aggregation did not significantly affect model outcomes, with predictions primarily dependent on home range estimates. Our survey results suggest considerable spatial variation in glider density across its range. The abundance estimates provide a baseline for future conservation initiatives and highlight the importance of ongoing monitoring and the application of advanced modeling techniques to inform species management. We estimated the total abundance of the Endangered Mahogany Glider (Petaurus gracilis) using camera trapping and a Bayesian integrated species distribution model. Our results suggest a median abundance of 2820 to 6036 individuals, with 2820 being the most conservative estimate. These findings provide a baseline for future monitoring and highlight the importance of advanced modeling techniques in species conservation.