Live Trapping Research Articles

The Hidden Diet: Determining the Distribution of the Threatened Julia Creek Dunnart (Sminthopsis douglasi) Using Eastern Barn Owl (Tyto javanica delicatula) Pellets.

Approximately 30% of the world's biodiversity has been threatened or driven to extinction since the 1500s, with Australia losing 10% of its endemic terrestrial mammal species in the last 200 years. The Julia Creek dunnart (Sminthopsis douglasi) is a threatened small mammal endemic to Queensland (Australia) that requires monitoring and protection. However, there is insufficient ecological data to determine its distribution adequately, and the species has only been sporadically caught in live trapping surveys, with no population size estimates. In the present study, eastern barn owl (Tyto javanica delicatula) pellet analysis was used to assess a range of locations for the presence of the Julia Creek dunnart as a prey species. Owl pellet deposit sites were chosen to encompass areas of high, medium, and low likelihood of Julia Creek dunnart occurrence based on Australian Government habitat models for the species with the goal of better understanding the species' distribution. In the analysis, Julia Creek dunnarts were present at four (of nine) locations, including all high-likelihood locations, half of the medium-likelihood locations, and no low-likelihood locations. This result supported the accuracy of the Australian Government habitat models. Results also demonstrated the importance of the long-haired rat (Rattus villosissimus) in the eastern barn owl diet during plague years. The research will assist with prioritizing sites for protection and monitoring of the Julia Creek dunnart. It also adds support to the utility of owl pellet analysis alongside or independent of traditional surveying techniques, such as live trapping, when targeting cryptic small mammal species.

Camera trap method effectively identifies small mammal species in forested habitats

Effective survey methods to detect small mammal species are often needed to develop conservation and management plans in forested ecosystems. The ability to use non-invasive methods to identify small mammal species in the field is particularly useful as live trapping can be time consuming and potentially harmful to the study species. We tested a camera trap method in a coastal redwood (Sequoia sempervirens) forest for small mammals, originally designed by Gracanin et al. (2019) and called the “selfie trap”, that uses a camera trap with a modified lens in a baited PVC tube. We determined if we could use this camera trap set-up on the ground to accurately identify small mammals to species to assess species diversity in a forested ecosystem as well as if it could withstand disturbance from larger mammals (e.g., bears). We surveyed for small mammals in areas of old-growth and second-growth coastal redwood forests in northwestern California. We detected 10 small mammal species and were able to identify most individuals to species including squirrel, chipmunk, mice, woodrat, shrew, vole and mole species. This camera trap set up also detected approximately 77% of small mammal species known to potentially occur in the area. Moreover, although larger mammals could interact with the camera trap set up, their disturbance was limited to when they were interacting with the trap, and the bait and camera set-up remained functional for subsequent small mammal detections. Thus, this method could be used instead of live trapping in complex forested ecosystems to effectively determine small mammal species presence, diversity, and activity levels, avoiding disturbance from large mammals.

Evidence of Persistence of Two Small, Sympatric Threatened Mammals (Dasyuridae) Following a Major Flood Event

ABSTRACTLarge‐scale, extreme flood events can potentially cause catastrophic declines in floodplain‐dwelling species, especially small terrestrial mammals. We undertook surveys to assess the status of two species of threatened Dasyurid mammals (Giles' Planigale Planigale gilesi and Fat‐tailed Dunnart Sminthopsis crassicaudata) to see if they were persisting in a region of northwest Victoria 12 months after a large‐scale flood event. We tested three possible detection techniques: live trapping using Elliott traps, camera traps with drift fences and thermal imaging transects. Surveys revealed that sympatric House Mice (Mus musculus) were in very high abundance following the flood. Both target species were detected using camera traps only, although at a very low rate. This demonstrates the limited availability of an effective survey technique for these cryptic species. These surveys resulted in the threatened Giles' Planigale being detected for the first time in 11 years in Victoria. There are two likely scenarios for the persistence of native mammals: in situ survival either by taking refuge in trees within small cavities for the duration of the flood event or on small island refuges nearby, or ex situ survival whereby animals perished in the flood event and individuals recolonised our sites from larger islands that remained dry throughout the flood. Further research is needed to understand the mechanisms by which small, ground‐dwelling mammals can survive large‐scale flooding events and the potential for competition with the invasive House Mouse following these disturbances.

Management of the feral European Rabbit, Oryctolagus cuniculus, on Akdamar Island, Lake Van, Türkiye

Lake Van is Türkiye’s largest lake, and within it lies Akdamar, a small seven-hectare island. In 2008, eight feral European rabbits were introduced to the island to attract tourists. With no natural predators, their population had increased to 3,000 by 2016, causing severe ecological damage, destroying almond trees, accelerating soil erosion, and damaging historical buildings through burrowing. In response, local authorities launched a management programme from 2016 to 2017, removing 1,500 rabbits through physical control methods such as live trapping, net trapping, and night spotlighting. However, funding shortages halted further efforts, and the population surged to an estimated 4,000–5,000 by 2023. The rabbits now occupy the entire island, degrading vegetation, diminishing ecosystem services, and threatening tourism. According to the assessment conducted in this study, the situation is classified as causing major ecological impacts under the Environmental Impact Classification for Alien Taxa and minor cultural effects under the Socio-Economic Impact Classification of Alien Taxa. Therefore, urgent, long-term management solutions are essential to prevent further degradation, with public awareness campaigns, community involvement, and education can help reduce human-mediated spread and promote responsible behaviour. Coupled with sustainable, effective management strategies, these efforts are vital to preserving the island’s ecosystem and cultural heritage.

Depauperate Small Mammal Assemblage in Wolin National Park (Poland): Effects of Insular Isolation, Topography, and Vegetation

Terrestrial small mammal species typically assemble according to plant communities, but multiple factors, including large-scale geographic patterns, influence their assemblage structure. Despite their ecological significance, small mammals are often underrepresented in biodiversity assessments, and many Polish national parks lack comprehensive surveys. This is also the case for Wolin National Park (WNP), Poland’s only national park on a coastal marine island, which is known for its unique bat fauna. Here, we surveyed small mammals in WNP using live and pitfall trapping, identifying only nine species—the lowest richness among the five regional national parks (which host 11–13 species based on trapping data alone). Rarefaction analysis indicated a very low probability of detecting additional species with further sampling. This unexpectedly low richness is likely linked to insular isolation and the park’s location at the edge of the regional distributions of three species. Cluster analysis revealed a key pattern in WNP’s small mammal assemblages: a division between two distinct landscape units—moraine hills and the alluvial delta—where Apodemus flavicollis and Apodemus agrarius were the predominant species, respectively. This division had a greater influence on assemblage clustering than local vegetation.

A case of non-metric multidimensional scaling of alpha (α), beta (β) and gamma (ɣ) biological diversity across the diverse forest habitats

The ecological intricacies that govern biodiversity is an essential understanding for the effective conservation of natural ecosystems. The study examines the impact of different forest habitats i.e. forests, rivers, and tourist areas on biodiversity across trees, birds, mammals, reptiles, and invertebrates. Field data were collected from 90 plots using various methods, such as quadrat sampling for trees, circular strip transects for aves, and live trapping for mammals and reptiles. Biodiversity indices (alpha, beta, gamma) were analyzed using the R programming environment, employing the vegan and iNEXT packages. Results revealed significant differences in species richness and composition among habitats. Forests exhibited high alpha diversity indices, with values of 86 for trees, 104 for aves, and 46 for mammals. River-associated forests showed increased species richness and evenness, with notable beta diversity, especially for invertebrates. Conversely, tourist areas displayed reduced species richness and slightly lower alpha diversity indices for trees and invertebrates. The Shannon diversity index was highest for trees (3.60) and lowest for invertebrates (1.00), highlighting the negative impact of human activities in tourist areas. Games-Howell tests and NMDS confirmed significant variation in species distributions between habitats, with rarefaction curves indicating the highest richness in forests. The study also linked conservation efforts, such as reforestation and anti-poaching activities, to improvements in biodiversity. Recommendations include prioritizing the protection of high-biodiversity areas, habitat restoration, ongoing monitoring, public education, and strict enforcement of environmental policies. These strategies are essential for enhancing biodiversity conservation and maintaining ecological integrity. The findings provide critical insights into the relationship between habitat types and biodiversity, supporting effective conservation and management practices.

Smart camera traps and computer vision improve detections of small fauna

Abstract Limited data on species' distributions are common for small animals, impeding conservation and management. Small animals, especially ectothermic taxa, are often difficult to detect, and therefore require increased time and resources to survey effectively. The rise of conservation technology has enabled researchers to monitor animals in a range of ecosystems and for longer periods than traditional methods (e.g., live trapping), increasing the quality of data and the cost‐effectiveness of wildlife monitoring practices. We used DeakinCams, custom‐built smart camera traps, to address three aims: (1) To survey small animals, including ectotherms, and evaluate the performance of a customized computer vision object detector trained on the SAWIT dataset for automating object classification; (2) At the same field sites and using commercially available camera traps, we evaluated how well MegaDetector—a freely available object detection model—detected images containing animals; and (3) we evaluated the complementarity of these two different approaches to wildlife monitoring. We collected 85,870 videos from the DeakinCams and 50,888 images from the commercial cameras. For object detection with DeakinCams data, SAWIT yielded 98% Precision but 47% recall, and for species classification, SAWIT performance varied by taxa, with 0% Precision and Recall for birds and 26% Precision and 14% Recall for spiders. For object detections with camera trap images, MegaDetector returned 99% Precision and 98% Recall. We found that only the DeakinCams detected nocturnal ectotherms and invertebrates. Making use of more diverse datasets for training models as well as advances in machine learning will likely improve the performance of models like YOLO in novel environments. Our results support the need for continued cross‐disciplinary collaboration to ensure that large environmental datasets are available to train and test existing and emerging machine learning algorithms.

Mammal diversity survey of Ko Pha-ngan in Surat Thani Province, Thailand.

This study aims to survey mammal diversity on Ko Pha-ngan, located 80 km off the east peninsular coast of Surat Thani province, Thailand. Thirteen camera trap sites, 32 transects, six drift line fence traps, five mist net trap sites, and nine live trap sites placed in human settlement, human-disturbed forest, and national park forest from February 2021 to September 2023 were utilized. A total of 28 mammal species of eight orders, 17 families, and 21 genera were found. Among them, 11 species are flying mammals while the remaining are terrestrial. Of the species detected, Manisjavanica (pangolin) is critically endangered, while Nycticebuscoucang (slow loris monkey) is endange by IUCN Red List. Additionally, Rusaunicolor (sambar deer) is vulnerable and Pteropuscf.hypomelanus (island flying fox), Trachypithecusobscurus (dusky leaf monkey), and Ratufabicolor (giant black squirrel) are near threatened. These findings highlight the need to conserve and protect both national park forest and human-disturbed forest from anthropogenic pressures due to the finite area of an island, in which potential local extinction risk is higher.

Initial Effects of Clearcutting and Partial Retention Forest Harvesting Methods on Some Small Mammals in Northern British Columbia

British Columbia’s interior forests have been heavily subjected to logging, burning, and beetle outbreaks for decades. Partial retention forest harvesting may be a method that could mitigate some of the negative effects of clearcut harvesting on wildlife. We conducted live trapping for small mammals at John Prince Research Forest in north-central BC to estimate species diversity, population density, and habitat use across a gradient of overstory tree retention. We detected 7 species, with diversity highest in the uncut forest (control) relative to the clearcut (control mean Shannon Index = 1.01, SE = 0.14) and partial retention treatments (30% and 60% retention, mean Shannon Indices = 0.99, 0.98; SE = 0.17, 0.17), and significantly lower in the seed tree treatment (mean = 0.63, SE = 0.17, p = 0.02). Greater population densities of North American deer mouse (Peromyscus sonoriensis) and southern red-backed vole (Myodes gapperi) in partially harvested stands, as estimated with spatially explicit capture-recapture models, support these practices for supporting populations of forest specialists. More experimental approaches to forest operations are needed across larger spatial scales, such as adaptive management of forest harvest methods with rigorous wildlife monitoring to ensure ecological objectives are met.

Owl Pellet Content Analysis Proves an Effective Technique to Monitor a Population of Threatened Julia Creek Dunnarts (Sminthopsis douglasi) Throughout a Native Rodent Plague.

Logistical, environmental and temporal considerations can limit the effectiveness of long-term live trapping for small mammals in remote environments. Owl pellet content analysis offers a low-cost, non-invasive alternative to live trapping, as it is generally reflective of prey abundance within the broader small mammal community. One species to which this detection technique could be readily applied is the threatened Australian dasyurid, the Julia Creek dunnart, Sminthopsis douglasi. Most population information is outdated, and the species is notoriously difficult to monitor. Here, we aimed to monitor S. douglasi and other small terrestrial vertebrates over time and in relation to a native long-haired rat (Rattus villosissimus) plague, assessing their occurrence as dietary items in eastern barn owl (Tyto javanica delicatula) pellets collected at Toorak, north-west Queensland, Australia. A total of 1007 individual vertebrates were identified from 706 barn owl pellets spanning 3 present-day collections (2023-2024), with further analysis incorporating a prior published historical dataset (1994-2001, 210 pellets). We demonstrated a shift in Toorak small mammal community structure both over time and in response to an active R. villosissimus plague. Despite declines across present-day pellet collections, S. douglasi was always detected in high abundance, peaking at 30.75% of all individuals. Cumulative probability of detection indicated that analysis of owl pellets was highly effective at detecting S. douglasi (within 20 pellets) despite the ongoing rodent plague, which has undermined the effectiveness of parallel live trapping efforts across the region. Owl pellet analysis is thus an effective methodology for rapidly assessing S. douglasi populations and should be incorporated into both S. douglasi and other small mammal species monitoring regimes.

The continuing search for a better mouse trap: Two tests of a practical, low-cost camera trap for detecting and observing small mammals.

The advent of digital wildlife cameras has led to a dramatic increase in the use of camera traps for mammalian biodiversity surveys, ecological studies and occupancy analyses. For cryptic mammals such as mice and shrews, whose small sizes pose many challenges for unconstrained digital photography, use of camera traps remains relatively infrequent. Here we use a practical, low-cost small mammal camera platform (the "MouseCam") that is easy and inexpensive to fabricate and deploy and requires little maintenance beyond camera service. We tested the MouseCam in two applications: a study of small mammal species composition on two transects across a barrier island and a study of small mammal occupancy along a subtle elevation gradient in a mainland forest. The MouseCam was reasonably efficient, with over 78% of all images containing a recognizable small mammal (mouse, vole, rat or shrew). We obtained an accurate estimate of species composition on the island transects, as indicated by comparison with both concurrent and long-term trapping records for the same transects. MouseCams required a smaller expenditure of personnel and transportation resources than would be required for live trapping. They also detected subtle elevation-related differences in species occupancy in the mainland forest for the marsh rice rat, with the species occurring at lower elevations in the forest. This is consistent with the typical occurrence of the marsh rice rat in marshes and wetlands. We also tested devices (barriers, runways) designed to reduce disturbance by mesopredators (e.g., raccoons). Adding an internal barrier to the MouseCam did not reduce use by white-footed mice, whereas adding an external runway did. We believe specialized small mammal camera-based sensors may have wide applicability in field studies of small mammal distribution, abundance and biology.

Conservation status of Sorex alpinus within a community of small mammals in the Oberpfälzer Forest (Bavaria, Germany): results of a 16-year study (Eulipotyphla: Soricidae)

We collected data on small mammals at the southeastern foothills of the Oberpfälzer Forest (Upper Palatinate Forest), a low mountain range along the border between Bavaria and the Czech Republic. Special attention was paid to the conservation status of the Alpine shrew, Sorex alpinus. Over a 16-year period, 2009–2024, live trapping was carried out each year from mid/end September to mid/end October. A total of 2,976 small mammals of 15 species (eight rodent species, six insectivore species, and one carnivore species) were captured, with the most abundant species being the bank vole (Clethrionomys glareolus), followed by the yellow-necked mouse (Apodemus flavicollis) and the wood mouse (A. sylvaticus). The bank vole and yellow-necked mouse populations showed remarkable fluctuations, with peaks and crashes in subsequent years. Shrews were represented by six species, including the bicoloured white-toothed shrew (Crocidura leucodon), whose presence in a closed woodland is rather unusual. The Alpine shrew was recorded with a total of 26 specimens (0–4 individuals caught per year). This makes it by far the rarest of all the Soricinae species that have been recorded. We consider the Alpine shrew to be endangered in the lower mountain ranges of Bavaria due to climate change and habitat shift.

Temporal and interspecific comparisons reveal shifts in the distributions of two Florida skunk species

Abstract Understanding the distribution of wildlife species is key to their effective conservation and management. Comparing distributions of similar species can provide valuable insights regarding range overlap and how overlap changes over time. We estimated the geographic distributions of 2 skunk species, the eastern spotted skunk (Spilogale putorius) and the striped skunk (Mephitis mephitis), in Florida, USA, for historical (1997–2002) and contemporary (2017–2022) periods using opportunistic presence data (e.g., public sightings, camera trap records, live trap records). For each species, we produced range models at 2 levels: a generalized boundary (range extent) using a concave hull and a more detailed delineation (occupied range) using kernel density estimation. We expected spotted skunk range to decline (as it has elsewhere), striped skunk range to remain stable, and both species' ranges to have a relatively high geographic overlap. The contemporary models show spotted skunk range encompassing 26% of Florida land area, primarily in southern and coastal Florida, and striped skunk range encompassing 55% of Florida land area, primarily in northern and interior Florida. Range size for spotted skunk declined by approximately 30% between periods, although range expansion occurred in some localized areas. Range size for striped skunk was stable over time, with some localized contractions and expansions. Considerable temporal shifts occurred in skunk distribution, where only 34% of spotted skunk and 54% of striped skunk occupied range remained spatially constant between periods. Divergent geographic use between the 2 species increased over time, yielding a low range overlap of 23% between their contemporary occupied ranges. Our study fills a spatial data gap in skunk research, can inform state‐ or species‐level conservation decisions for spotted skunk, and supports the need for further research on habitat requirements of skunks in Florida.

Knowledge, risk perceptions and practices regarding rodents and their associated pathogens: environmental consultants in Chile

BackgroundRodents play essential ecological roles but are also significant reservoirs of zoonotic pathogens, posing risks to humans. Individuals with frequent occupational contact with rodents face an elevated risk of exposure to rodent-borne diseases. This study examines the knowledge, risk perceptions, and practices of Chilean environmental consultants (ECs) concerning rodents and rodent-borne diseases.MethodsA 32-item questionnaire, which focused primarily on biologists, veterinarians, and environmental engineers, was administered. The questionnaire included closed, open-ended, and semi-open-ended questions. Data analyses, performed using R software, involved calculating frequencies and proportions for questions related to knowledge of rodents and rodent-borne diseases, rodent management and handling, biosafety procedures, and training. Additionally, generalized linear models (GLMs) were used to assess knowledge of rodent hosts and diseases, whereas correspondence analysis was used to examine associations between EC characteristics (undergraduate fields of study and years of experience) and responses regarding risk perception and the importance of zoonotic disease training.ResultsCompleted questionnaires were received from 206 ECs. Although the ECs demonstrated a strong awareness of hantavirus cardiopulmonary syndrome, identifying it as a significant rodent-borne threat, knowledge gaps were evident regarding the specific role of certain rodent reservoir species and other rodent-borne diseases in Chile. For example, leptospirosis was well recognized, particularly among veterinarians, whereas emerging zoonoses such as scrub typhus was rarely mentioned. The study also revealed the frequent use of live trapping and direct handling of rodents, resulting in injuries to 32% of the respondents. Despite the widespread use of personal protective equipment, key elements such as respiratory protection and disposable suits were underutilized, and inadequate cleaning practices for traps were reported. Nevertheless, ECs expressed a willingness to participate in zoonotic disease training, underscoring the need for further education.ConclusionsThis study highlights the critical need for ongoing education for ECs on rodent reservoirs, diseases, and biosafety measures to enhance their safety and reduce the risk of zoonotic infections. The findings offer valuable insights for developing strategies aimed at improving awareness and strengthening biosafety practices within this occupational group.

Comparing Methods of Detecting an Elusive Dasyurid Marsupial, the Threatened Julia Creek Dunnart (Sminthopsis douglasi), in Central Western Queensland, Australia.

The Julia Creek dunnart, Sminthopsis douglasi, is a small, threatened carnivorous marsupial occurring in scattered populations in the grasslands of central and northwestern Queensland, Australia. The distribution of the species is largely unknown due to sporadic survey efforts and its historically low detection using traditional live trapping methods. There is an urgent need to determine the best methods of detection to optimise survey methodologies and more effectively manage species conservation efforts. In this study, we compared the effectiveness of live (Elliott) traps, baited white flash camera traps and thermal imagery binocular surveying for detecting S. douglasi. We deployed 40 white flash camera traps at two sites in Bladensburg National Park (south of Winton), where the species is known to occur, for three consecutive periods between June and November 2022. Four comparative sessions of live trapping were undertaken between April and August 2022 at the same locations. During the live trapping periods, a total of 12 nights of surveying were conducted with thermal imagery binoculars in a preliminary assessment of the technique. The total live trapping effort was 3600 trap nights (approximately 700 trap nights per site in each trapping event). Live trapping resulted in 12 detections of individual S. douglasi from 19 total captures. The highest trap success on a given trapping session was 1.71%, and overall trap success from both sites across all sessions was 0.53%. In comparison, baited camera traps (deployed facing the ground at 70 cm range) took 1,269,884 images over 5383 trap nights. There were 11 confirmed images of S. douglasi, on three individual occasions, which represented 2.10% of all small mammal captures and just 0.0009% of the total images. Four species of small mammals were detected using camera traps, whereas live trapping detected only two species. No small mammals were detected on any of the 12 thermal binocular surveys. Overall, our study highlights the comparative high utility of traditional live trapping for detecting S. douglasi. This research provides a framework for ongoing monitoring of the Bladensburg National Park population. It will be more broadly beneficial for informing the best detection techniques of S. douglasi in ongoing work investigating the overall distribution of the species. Similar studies assessing multiple detection methods for small terrestrial mammals have shown an advantage of white flash camera traps compared to other traditional detection techniques. Our contrasting results serve as a reminder that the utility of different techniques for detecting small mammals is best assessed on a species-by-species basis.

Hantavirus Pulmonary Syndrome Outbreak Anticipation by a Rapid Synchronous Increase in Rodent Abundance in the Northwestern Argentina Endemic Region: Towards an Early Warning System for Disease Based on Climate and Rodent Surveillance Data.

Hantavirus pulmonary syndrome (HPS) is an American emerging disease caused by the rodent-borne virus genus Orthohantavirus (Family: Hantaviridae: Order: Elliovirales Class: Bunyaviricetes). In Argentina, almost half of the HPS infections occur in the northwestern endemic region. In this study, we monitored rodent abundance during 2022 and 2023 in three sites with different sampling methods (removal trapping, live trapping and hunted rodents by domestic cats) to evaluate their relationship with human infections. We found a similar pattern of variation in rodent abundance across time, and particularly a synchronous rise of rodent abundance that anticipated an HPS outbreak in 2023. Our dynamic regression models revealed a positive relationship between HPS cases and rodent abundance with a three-month lag, as well as rainfall with an eight-month lag. Our results provide a framework for the planning and implementation of public health prevention campaigns based on climatology and rodent monitoring. Domestic cats bringing rodents into houses can be an overlooked risk factor, particularly if viral shedding of infected rodents is magnified by stress. HPS is a disease of public health concern due to its high mortality rate, the lack of a specific therapeutic treatment and no vaccine. Thus, prevention of infections is of the utmost importance.

Rediscovery of the Bavarian pine vole (Microtus bavaricus) in Germany

Abstract We report the rediscovery of Microtus bavaricus in Germany, a small mammal that had not been recorded here in more than 60 years. Between 2012 and 2014, a citizen science project addressed cat owners and farmers to collect rodents killed by cats and traps. Until 2017, we conducted 3,432 live trap nights to rediscover the species in and around the area of its discovery. However, only a three-step approach (screening large areas for the occurrence of pine voles using camera trapping, live trapping for collecting genetic material, DNA-barcoding) allowed for the rediscovery of this elusive species near Mittenwald in 2023.

Home range overlaps of the brushtail possum (Trichosurus vulpecula): implications for disease transmission

Understanding how bovine tuberculosis (TB) is maintained in wildlife reservoirs is critical for the management of this disease impacting cattle in many countries. For the primary wildlife reservoir of the disease in New Zealand, the brushtail possum (Trichosurus vulpecula), transmission of this contagious bacterial disease among possums is often assumed to be linked to home range overlap. Identifying drivers of possum home range, and home range overlap between individuals, is thus important for informing wildlife reservoir TB management in New Zealand. We monitored four sub-populations of free-living possums in New Zealand native forests during 10 consecutive months using live trapping, to give the first direct insight into how the frequency and area of overlaps alters with density, sex and age. A total of 832 individuals were captured (average 9.3, range from 1 to 40 captures per animal with a median value of 7) and 35,820 home range overlaps were recorded. Both the number and area of overlaps were significantly associated with age class, with 66.6% of overlaps occurring between adults, 30% between adults and juveniles, and only 3.4% between juveniles. Overall, adult males showed significantly higher numbers of overlaps than expected, while adult and juvenile females showed significantly lower numbers of overlaps than expected and no differences were observed in juvenile males. In addition, males exhibited more and larger overlaps than females. The number and size of overlaps per individual decreased with increasing local population density. Understanding shared areas of activity among individuals can provide insights into the interactions occurring and potential pathways for diseases transmitted by contact such as TB. These results can inform to develop effective strategies for the control of diseases carried and dispersed by possums.

Density of a cryptic Australian small mammal: The threatened Julia Creek dunnart (Sminthopsis douglasi).

Globally, hundreds of mammal species face the threat of extinction in the coming decades, and in many cases, their ecology remains poorly understood. Fundamental ecological knowledge is crucial for effective conservation management of these species, but it is particularly lacking for small, cryptic mammals. The Julia Creek dunnart (Sminthopsis douglasi), a threatened, cryptic carnivorous marsupial that occurs in scattered populations in the central west of Queensland, Australia, was once so poorly studied that it was believed extinct. Sporadic research since its rediscovery in the early 1990s has revealed that S. douglasi is distributed across land at risk from many threats. Fundamental knowledge of S. douglasi population density is urgently required to inform conservation management at key sites, yet the species has historically proven hard to detect. Indeed, the status of the largest known population of S. douglasi, in Bladensburg National Park, is unknown. Here, we conducted a population study on S. douglasi at two sites within Bladensburg National Park via live mark-recapture surveys during 2022 and 2023. From likelihood-based spatially explicit capture-recapture (SECR) modelling we provide the first estimates of density and population size for S. douglasi. Live trapping resulted in captures of 49 individual S. douglasi (with 83 captures total, including recaptures). We estimated S. douglasi to occur at a density of 0.38 individuals ha-1 (0.25-0.58) at one site and 0.16 individuals ha-1 (0.09-0.27) at another site, with an estimated mean population size in suitable habitat at Bladensburg National Park of 1211 individuals (776-1646). Our S. douglasi density estimates were similar to that reported for other threatened small mammals in Australia. We also found evidence of extreme S. douglasi population fluctuations over time at Bladensburg National Park, which is of concern for its future conservation. Our study has provided the first estimate of density for S. douglasi, a threatened dasyurid species from the Mitchell Grass Downs of central western Queensland, Australia. Our research provides crucial population data to assist the management of this poorly studied species. We demonstrate a method that can be applied to species with low detection probability to ultimately help address the mammal extinction crisis faced by Australia and the rest of the world.

Багаторічна динаміка угруповань ссавців у Національному природному парку «Гомільшанські ліси» (2015-2022)

The article analyses survey data of small mammals collected by the method of live trapping on two trap lines, the dynamics of beaver numbers in one of the colonies, and random encounters of roadkill mammals in the Homilshanski Lisy National Nature Park and nearby areas. The data were collected in 2015–2022 during field research. Small mammals were studied on the second, pine barren terrace of the Siverskyi Donets River. Two trap lines (trapping trenches with five traps in each, made of two-litre PET bottles) were laid in the pine forest. The first was in an undamaged area of the forest, and the second was in an area damaged by a grassland fire in 2005 and currently undergoing natural forest ecosystem restoration. A total of six species of small mammals were recorded during the survey period, including Sylvaemus uralensis, Myodes glareolus, Sylvaemus tauricus, Mus musculus, Sorex araneus, Crocidura suaveolens, as well as an unidentified Sylvaemus sp. The research has shown that, during the years of peak numbers, not only the abundance of individual species increases, but also the number of recorded species. The beaver colony, where the surveys were conducted, is located in a floodplain on the left bank of the Siverskyi Donets River in a system of three small lakes interconnected by channels. There are also seasonal peaks in the numbers of roadkill species. In total, 17 species have been recorded dead on the roads, which is almost a third of all mammalian species of the Homilshanski Lisy National Nature Park (as of 2020, 60 species have been registered in the Park). It was found that there is a positive correlation between population increase in different groups of mammals and the frequency of deaths of different groups of mammals and the number of species killed on roads. We identified the places where certain anthropogenic factors (poaching, road repairs) are superimposed on natural phenomena and how this affects the state of fauna protection in the National Nature Park. In general, the population dynamics of mammals over the years correlates with the dynamics of encounters of roadkill birds, reptiles, and amphibians, which we also studied during this period. We have proposed a number of recommendations for developing a strategy for the protection of various species in the National Nature Park and its protected area: measures to reduce the risk of animal death on highways.