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Egg predation is the primary cause of nest failure for tundra nesting birds. Taverner's Cackling Geese (Branta hutchinsii taverneri) breeding on the North Slope of Alaska have increased approximately 5-fold over the last 25 years and are now one of the most encountered waterbird species breeding at our study site on the coastal plain of Arctic National Wildlife Refuge. This rapid population growth may offer a new food resource for egg predators, impacting predator populations, which in turn could have cascading effects for other tundra nesting bird species, many of which are declining. To determine how the population growth of geese may affect the nest-predator community, and to establish a baseline of predators as the area is impacted by climate change and development, we used digital time-lapse cameras to record predation events at Cackling Goose nests. We determined fate for 52 nests in 2017, 2019, and 2021, of which 20 were depredated. The most frequent predator differed each year. Red foxes (Vulpes vulpes) were responsible for 89% of depredations in 2017 and wolverines (Gulo gulo) for 67% in 2019, and those species only depredated nests in those single years. In contrast, Arctic foxes (Vulpes lagopus) were responsible for nest failure in all years, but did not exceed 40% of total depredations in any year. Golden Eagles (Aquila chrysaetos) were an unexpected egg predator, depredating 2 nests. Our results were notably different than work on other Arctic goose species, where Arctic foxes were the primary predator. The inter-annual variability of egg predators at this Arctic Refuge study site provides insights into complex predator–prey interactions on the Arctic Coastal Plain. La depredación de huevos es la causa primaria del fracaso de nido para aves que anidan en la tundra. El ganso Branta hutchinsii taverneri, que se reproduce en la pendiente Norte de Alaska ha quintuplicado su presencia en los últimos 25 años y ahora es una de las especies acuáticas en reproducción más observadas en nuestro sitio de estudio en la planicie costera del Arctic National Wildlife Refuge. Este crecimiento poblacional acelerado puede ofrecer una nueva fuente de alimentación para depredadores de huevos, impactando las poblaciones de depredadores, que podría tener efectos en cascada en otras especies de aves que anidan en la tundra, muchas en declive. Para determinar cómo el crecimiento poblacional de gansos puede afectar la comunidad de depredadores de nidos y establecer una línea base de depredadores en un área que es impactada por el cambio climático y el desarrollo, usamos cámaras digitales con temporizador automático para registrar eventos de depredación en nidos de ganso Branta hutchinsii. Determinamos el destino de 52 nidos en 2017, 2019 y 2021, de los cuales 20 fueron depredados. El depredador más frecuente varió cada año. Los zorros rojos (Vulpes vulpes) fueron responsables del 89% de las depredaciones en el 2017, mientras que los glotones (Gulo gulo) lo fueron del 67% en el 2019, y esas especies solo depredaron nidos en esos años. En contraste, el zorro artico (Vulpes lagopus) fue responsable de fracaso de anidación durante todos los años, pero su cuota de depredación no excedió el 40% en ninguno de los años. El águila real (Aquila chrysaetos) fue un depredador inesperado, depredando 2 nidos. Nuestros resultados fueron notablemente diferentes que otros estudios con otras especies de gansos silvestres del Artico, donde los zorros articos fueron los depredadores primarios. La variación interanual de depredadores de huevos en este sitio de estudio en el Refugio Artico proporciona información en interacciones complejas depredador-presa en la Planicie Costera Artica. Palabras clave: cámaras para vida silvestre, depredador de huevos, ganso Branta hutchinsii taverneri, gansos de anidación artica, Planicie Costera Artica. [ABSTRACT FROM AUTHOR]

Highways can fragment habitat and be a significant mortality source for mammals. Wildlife exclusion fencing has been shown to reduce wildlife-vehicle collisions, but can also prevent animals from escaping the highway corridor if they enter at access roads or at fence ends. Earthen escape ramps, or “jumpouts,” have been proposed as a possible solution but remain relatively untested. From 2012-2014, we used wildlife cameras to continuously document wildlife use of four jumpout ramps constructed as part of a 2.5-mile wildlife exclusion fence project along Highway 101 near San Luis Obispo, California. Mule deer occasionally used the jumpouts, but quantifying the rate of utilization was confounded by repeated visits by the same individuals. Male and female deer appeared to have different responses to the jumpouts, which warrants deeper investigation using additional data collected from further monitoring through mid-2017. The longer dataset will also better document how individual deer learn to use the jumpouts. Fenced highways can also reduce connectivity unless there is sufficient use of crossing structures. We documented mountain lion, bobcat, black bear, and mule deer used culverts and underpasses in and adjacent to the wildlife fence zone from 2012-2014. Mule deer used the large underpasses almost exclusively, and rarely if ever used culverts. Bear used a wider variety of structures, and bobcats were detected at almost every site and at a higher rate than the other taxa. Mountain lion detections were quite rare, likely due to lower population density in the study area. We propose a deeper multivariate analysis of the factors influencing these species’ use of culverts including culvert dimensionality, nearby habitat, and proximity to cover, based on an expanded dataset of up to five years of continual monitoring at certain sites. The goal of these analyses is to provide information that will help reduce wildlife-vehicle collisions while facilitating regional wildlife connectivity.

Time is a fundamental component of ecological processes. How animal behavior changes over time has been explored through well-known ecological theories like niche partitioning and predator–prey dynamics. Yet, changes in animal behavior within the shorter 24-hr light–dark cycle have largely gone unstudied. Understanding if an animal can adjust their temporal activity to mitigate or adapt to environmental change has become a recent topic of discussion and is important for effective wildlife management and conservation. While spatial habitat is a fundamental consideration in wildlife management and conservation, temporal habitat is often ignored. We formulated a temporal resource selection model to quantify the diel behavior of 8 mammal species across 10 US cities. We found high variability in diel activity patterns within and among species and species-specific correlations between diel activity and human population density, impervious land cover, available greenspace, vegetation cover, and mean daily temperature. We also found that some species may modulate temporal behaviors to manage both natural and anthropogenic risks. Our results highlight the complexity with which temporal activity patterns interact with local environmental characteristics, and suggest that urban mammals may use time along the 24-hr cycle to reduce risk, adapt, and therefore persist, and in some cases thrive, in human-dominated ecosystems.

A cost-efficient approach to long-term monitoring is to focus on one species or group of organisms as indicators of ecological condition. Through the use of autonomous monitoring technologies, monitoring programs can efficiently expand the biological community surveyed and inferences made. Amphibians have been monitored in Yellowstone and Grand Teton national parks by the Greater Yellowstone Inventory and Monitoring Network (GRYN) since 2006, yet other taxa dependent on wetlands have not been systematically studied. Our main aim was to explore what additional insights we could gain about wetland biodiversity by combining GRYN’s amphibian surveys with multiple autonomous technologies. We deployed wildlife cameras and acoustic recorders (for audible and ultrasonic sounds) at 4 permanent wetlands in Grand Teton National Park, WY during early and late summer 2017 and used descriptive metrics to summarize our findings. During GRYN’s surveys, 3 of 4 native amphibians were detected. With autonomous monitoring tools, we also documented avian and mammalian communities and detected changes in the degree of activity over the summer. Combining multiple, complementary technologies with field-based surveys provides a more comprehensive picture of wetland biodiversity and enhances insights about ecological condition and change.

Living shoreline stabilization is a technique that utilizes plants and other natural elements to protect estuarine coasts. Research has provided minimal information about which vertebrate species utilize living shorelines post-deployment. For this project, ten wildlife cameras were placed along a living shoreline site in Canaveral National Seashore (CANA) to document which vertebrate species utilize the living shoreline and surrounding vegetation. This shoreline was stabilized with red mangroves (Rhizophora mangle) and eastern oyster (Crassostrea virginica) shell bags in June 2019. The cameras, activated by motion sensors, remained at the site for five days a month for seven months (September 2019 - March 2020) to identify vertebrates and their behaviors. Wildlife camera footage provided data on which vertebrate species visited the site, what behaviors were exhibited, and what impact (if any) the vertebrate species had on the stabilization materials. Birds (i.e., wading birds and songbirds) and mammals (i.e., raccoons, feral hogs, deer, opossums, rats, and bobcats) were observed (total n=1,608). The North American raccoon (Procyon lotor; n=799) and the feral hog (Sus scrofa; n=523) were the most abundant vertebrates. Solitary foraging was the most observed behavior (n=552) among all vertebrate species, followed by group foraging (n=518). Both individuals and groups of P. lotor (n=9 for mangroves; n=38 for shell bags) and S. scrofa (n=6 for mangroves; n=0 for shell bags) contacted the stabilization materials. No consumption or dislodgement of stabilization materials by any species was observed. Results indicate that living shorelines provide habitat for many vertebrates (25 unique species) and these species do not negatively impact stabilization materials less than one-year post-deployment. [ABSTRACT FROM AUTHOR]

Human activity affects plant and animal populations across local to global scales, and the management of recreation areas often aims to reduce such impacts. Specifically, by understanding patterns of human activity and its influence on animal populations, parks and recreation areas can be managed to provide spatial and temporal refuge to wildlife most sensitive to this type of human disturbance. However, additional research is necessary to understand how human activity influences wildlife populations, habitat use, and activity patterns for a diversity of wildlife species. We studied the potential impacts of human activity (as measured by nonmotorized recreationists) on populations and activity patterns of 12 mammal species, including herbivores and carnivores, from 63 motion‐activated cameras that sampled game trails and human trails with varying degrees of human activity along the Front Range of Colorado. Human activity was greatest during the day and minimal or absent during the night. All wildlife species in our study used human trails, although the extent to which human recreation altered the occupancy, relative habitat use, and activity patterns of wildlife varied across species, where some animals appeared to be more influenced by human activity than others. Some species (e.g., fox squirrel, red fox, and striped skunk) did not demonstrate a response to human activity. Other species (e.g., black bear, coyote, and mule deer) altered their activity patterns on recreation trails to be more active at night. Across all wildlife, the degree to which animals altered activity patterns on human trails was related to their natural activity patterns and how active they were during the day when human activity was greatest; species that exhibited greater overlap in natural activity patterns with humans demonstrated the greatest shifts in their activity, often exhibiting increased nocturnal activity. Further, some species (e.g., Abert's squirrel, bobcat, and mountain lion) exhibited reduced occupancy and/or habitat use in response to human recreation. Managing spatial and temporal refuges for wildlife would likely reduce the impacts of human recreation on animals that use habitat in proximity to trail networks. [ABSTRACT FROM AUTHOR]

Broad-scale abundance estimates of the southern hairy-nosed wombat population use a proxy measure based on counting the number of active burrows, which is multiplied by an index of ‘wombats/active burrow’. However, the extant indices were calculated in the 1980s, prior to the use of calicivirus to control rabbits, and used invasive monitoring methods which may have affected the results. We hypothesise that the use of video might provide a logistically simple, non-invasive means of calculating updated indices. To this end, motion-activated, infra-red still and video cameras were placed at various distances outside active wombat burrows in the South Australian Murraylands and Eyre Peninsula regions. The captured imagery was inspected to determine how often the burrow was occupied by one or more wombats, and how effective the cameras were at detecting wombat activity. Video data was clearly superior to the still imagery, with more than twice as many burrow occupancies being positively identified (still: 43%). The indices of wombats/active burrow calculated based on video imagery were: Murraylands: 0.43, Eyre Peninsula: 0.42. 1948 false positive videos were recorded, of which 1674 (86%) occurred between noon and sunset.

Contemporary methods for sampling wildlife populations include the use of remotely triggered wildlife cameras (i.e., camera traps). Such methods often result in the collection of hundreds of thousands of photos that must be identified, archived, and transformed into data formats required for statistical analyses., Cpw Photo Warehouse is a freely available software based in Microsoft Access® that has been customized for this purpose using Visual Basic® for Applications ( VBA) code. Users navigate a series of point-and-click menu items that allow them to input information from camera deployments, automatically import photos (and image data stored within the photos) related to those deployments, and store data within a relational database. Images are seamlessly incorporated into the database windows, but are stored separately from the database., The database includes menu options that (i) facilitate identification of species within the images, (ii) allow users to view and filter any subset of the databased on study area, species, season, etc., and (iii) produce input files for common analyses such as occupancy, abundance, density and activity patterns using Programs mark, presence, density and the r packages 'secr' and 'overlap'., Our database makes explicit use of multiple observers, which greatly enhances the efficiency and accuracy with which a large number of photos can be identified. Modular subsets of the data can be distributed to an unlimited number of observers on or off site for identification. Modules are then re-incorporated into the database using a custom import function. [ABSTRACT FROM AUTHOR]

Automatically triggered cameras taking photographs or videos of passing animals (camera traps) have emerged over the last decade as one of the most powerful tool for wildlife research. In parallel, a wealth of camera trap systems and models has become commercially available, a phenomenon mainly driven by the increased use of camera traps by sport hunters. This has raised the need for developing criteria to choose the suitable camera trap model in relation to a range of factors, primarily the study aim, but also target species, habitat, trapping site, climate and any other aspect that affects camera performance. There is also fragmented information on the fundamentals of sampling designs that deploy camera trapping, such as number of sampling sites, spatial arrangement and sampling duration. In this review, we describe the relevant technological features of camera traps and propose a set of the key ones to be evaluated when choosing camera models. These features are camera specifications such as trigger speed, sensor sensitivity, detection zone, flash type and flash intensity, power autonomy, and related specifications. We then outline sampling design and camera features for the implementation of major camera trapping applications, specifically: (1) faunal inventories, (2) occupancy studies, (3) density estimation through Capture-Mark-Recapture and (4) density estimation through the Random Encounter Model. We also review a range of currently available models and stress the need for standardized testing of camera models that should be frequently updated and widely distributed. Finally we summarize the "ultimate camera trap", as desired by wildlife biologists, and the current technological limitations of camera traps in relation to their potential for a number of emerging applications. [ABSTRACT FROM AUTHOR]

Time is a fundamental component of ecological processes. How animal behavior changes over time has been explored through well-known ecological theories like niche partitioning and predator-prey dynamics. Yet, changes in animal behavior within the shorter 24-hr light-dark cycle have largely gone unstudied. Understanding if an animal can adjust their temporal activity to mitigate or adapt to environmental change has become a recent topic of discussion and is important for effective wildlife management and conservation. While spatial habitat is a fundamental consideration in wildlife management and conservation, temporal habitat is often ignored. We formulated a temporal resource selection model to quantify the diel behavior of 8 mammal species across 10 US cities. We found high variability in diel activity patterns within and among species and species-specific correlations between diel activity and human population density, impervious land cover, available greenspace, vegetation cover, and mean daily temperature. We also found that some species may modulate temporal behaviors to manage both natural and anthropogenic risks. Our results highlight the complexity with which temporal activity patterns interact with local environmental characteristics, and suggest that urban mammals may use time along the 24-hr cycle to reduce risk, adapt, and therefore persist, and in some cases thrive, in human-dominated ecosystems., Competing Interests: TG, MF, BG, AA, JA, MA, AC, DD, DG, EL, MM, TR, CS, CS, HS, TS, JW, JB, KS, SM No competing interests declared

• We combined field surveys with autonomous tools to document wetland biodiversity. • Three of 4 extant native amphibians were detected during visual encounter surveys. • We recorded avian and mammal communities via cameras and acoustic recordings. • We also detected variation in the degree of activity over the summer. • Field surveys and technology together provide a more complete picture of diversity. A cost-efficient approach to long-term monitoring is to focus on one species or group of organisms as indicators of ecological condition. Through the use of autonomous monitoring technologies, monitoring programs can efficiently expand the biological community surveyed and inferences made. Amphibians have been monitored in Yellowstone and Grand Teton national parks by the Greater Yellowstone Inventory and Monitoring Network (GRYN) since 2006, yet other taxa dependent on wetlands have not been systematically studied. Our main aim was to explore what additional insights we could gain about wetland biodiversity by combining GRYN's amphibian surveys with multiple autonomous technologies. We deployed wildlife cameras and acoustic recorders (for audible and ultrasonic sounds) at 4 permanent wetlands in Grand Teton National Park, WY during early and late summer 2017 and used descriptive metrics to summarize our findings. During GRYN's surveys, 3 of 4 native amphibians were detected. With autonomous monitoring tools, we also documented avian and mammalian communities and detected changes in the degree of activity over the summer. Combining multiple, complementary technologies with field-based surveys provides a more comprehensive picture of wetland biodiversity and enhances insights about ecological condition and change. [ABSTRACT FROM AUTHOR]

Roads increase wildlife mortality and present a movement barrier for many species. While wildlife passages have been advocated as a solution to many of the problems associated with roads, they are expensive and many roads still have none. However, roads usually have a series of drainage culverts designed to allow water to cross underneath the road, which might also be used by some mammals. This study aims to (1) determine what variables influence the number of successful passages of drainage culverts by mammals, and to (2) parse the effects that these variables have on the entry into and subsequent full passage of drainage culverts by individual mammals, using cameras and animal track stations along a 20 km stretch of autoroute 10 in Southern Quebec (Canada). Overall, 20 species were observed outside of the drainage culverts, but only about half of them were detected making full crossings. While various species were often seen outside, only animals highly tolerant to water, including raccoons (Procyon lotor) and American mink (Neovison vison), were observed fully crossing the structures with regularity, whereas the number of full crossings was small (<8) for all other species. High-water levels and use of polyethylene as a construction material were the strongest deterrents for both the number of successful passages and the probability of entry into the culverts. While several variables (e.g., water level, structure material, moon luminosity, distance to forest) influenced culvert entry, none had an influence on a mammal's probability of complete passage once it had entered. The results imply that ordinary drainage culverts are unsuitable as substitutes for designated wildlife passages for mammals. We recommend the installation of designated wildlife passages and fences, and that in places where wildlife passages are not feasible, dry ledges be installed in existing drainage culverts to better allow small and medium-sized mammals to safely cross under roads while avoiding the water inside of the culverts. To our knowledge, this study is the first to successfully combine trail cameras inside of drainage culverts with track-box data in the adjacent habitat. Image 1 • We asked what species use ordinary drainage culverts under roads to cross safely. (80). • Twenty species were observed outside the drainage culverts, but only few used them. (82). • Only two species highly tolerant to water crossed the structures regularly. (74). • Water level and polyethylene as construction material were the strongest deterrents. (85). • Drainage culverts are unsuitable as substitutes for wildlife passages for mammals. (81). [ABSTRACT FROM AUTHOR]

Simple Summary: While many people have great affection for southern hairy-nosed wombats, they are also considered by others to be an agricultural pest, because of the damage they can cause to farmland and agricultural infrastructure. Therefore, we need to have a good understanding of how many wombats there might be and how the population is changing, if we are to make properly informed decisions on how to best manage them. Unfortunately, because wombats are nocturnal and live underground, and because they use a number of different burrows throughout their home ranges, counting them can be difficult. We used motion-activated cameras to record how often wombats use each burrow in order to develop a reliable method of counting wombats that we can apply at the broad scale. We found that, on average, there are around 0.43 wombats for each active burrow. The use of video cameras to record this information provided a much simpler and less invasive means of researching wombat behaviour than methods such as trapping. However, video cameras do have limitations that need to be considered, and researchers need to fully understand their capabilities and limitations before employing them in the field. Broad-scale abundance estimates of the southern hairy-nosed wombat population use a proxy measure based on counting the number of active burrows, which is multiplied by an index of 'wombats/active burrow'. However, the extant indices were calculated in the 1980s, prior to the use of calicivirus to control rabbits, and used invasive monitoring methods which may have affected the results. We hypothesise that the use of video might provide a logistically simple, non-invasive means of calculating updated indices. To this end, motion-activated, infra-red still and video cameras were placed at various distances outside active wombat burrows in the South Australian Murraylands and Eyre Peninsula regions. The captured imagery was inspected to determine how often the burrow was occupied by one or more wombats, and how effective the cameras were at detecting wombat activity. Video data was clearly superior to the still imagery, with more than twice as many burrow occupancies being positively identified (still: 43%). The indices of wombats/active burrow calculated based on video imagery were: Murraylands: 0.43, Eyre Peninsula: 0.42. 1948 false positive videos were recorded, of which 1674 (86%) occurred between noon and sunset. [ABSTRACT FROM AUTHOR]