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Camera traps are an important noninvasive tool used by scientists to monitor wildlife efficiently and at reduced costs. New camera trap features improve performance and encourage increased use by researchers and the public. Cellular transmission of image data, which provides users the ability to digitally receive images instead of retrieving or downloading images in the field is a useful new feature. Cellular data transmission has 2 key benefits for wildlife research in that it reduces travel time required for downloading image data and the uncertainty involving storage capacity of SD cards and battery life, and cellular transmission allows for near real‐time analysis of images, which could redistribute the time usually devoted to processing a large data set when the memory card is retrieved. Despite potential benefits, cellular transmission technology in camera traps is still new and questions remain about its reliability. Our objective was to determine the efficacy of cellular transmission technology in wildlife research by designing a camera trap study as part of a senior‐level class (Wildlife Management Applications and Planning; NREM 4522) project at Oklahoma State University. We used ArcGIS to generate a stratified random sample of trap locations, deploying five cellular transmission camera traps in open grassland and five in closed canopy forest areas from 5 September to 5 October 2021. We monitored the number of transmitted images each day online, and after camera trap retrieval, we compared the number of transmitted images to those stored on the memory card to determine transmission efficiency. Our data indicated the majority of the images taken each day were transmitted successfully; however, transmission efficiency (i.e., number transmitted divided by total number taken by the camera trap) tended to be lower in forested areas (47%) compared to open grassland (86%). Though cellular transmission technology shows promise, the combination of cellular signal, landscape features, and transmitted data quality may limit the effectiveness of cellular transmission technology for near real‐time data analysis. Based on our results, we recommend that researchers consider advantages and disadvantages of cellular transmission when designing studies and note that researchers may need to adopt an adaptive approach or conduct pilot testing that includes quantifying the transmission functionality. [ABSTRACT FROM AUTHOR]

Infectious diseases pose a significant threat to global health and biodiversity. Yet, predicting the spatiotemporal dynamics of wildlife epizootics remains challenging. Disease outbreaks result from complex nonlinear interactions among a large collection of variables that rarely adhere to the assumptions of parametric regression modeling. We adopted a nonparametric machine learning approach to model wildlife epizootics and population recovery, using the disease system of colonial black‐tailed prairie dogs (BTPD, Cynomys ludovicianus) and sylvatic plague as an example. We synthesized colony data between 2001 and 2020 from eight USDA Forest Service National Grasslands across the range of BTPDs in central North America. We then modeled extinctions due to plague and colony recovery of BTPDs in relation to complex interactions among climate, topoedaphic variables, colony characteristics, and disease history. Extinctions due to plague occurred more frequently when BTPD colonies were spatially clustered, in closer proximity to colonies decimated by plague during the previous year, following cooler than average temperatures the previous summer, and when wetter winter/springs were preceded by drier summers/falls. Rigorous cross‐validations and spatial predictions indicated that our final models predicted plague outbreaks and colony recovery in BTPD with high accuracy (e.g., AUC generally >0.80). Thus, these spatially explicit models can reliably predict the spatial and temporal dynamics of wildlife epizootics and subsequent population recovery in a highly complex host–pathogen system. Our models can be used to support strategic management planning (e.g., plague mitigation) to optimize benefits of this keystone species to associated wildlife communities and ecosystem functioning. This optimization can reduce conflicts among different landowners and resource managers, as well as economic losses to the ranching industry. More broadly, our big data–model integration approach provides a general framework for spatially explicit forecasting of disease‐induced population fluctuations for use in natural resource management decision‐making. [ABSTRACT FROM AUTHOR]

Habitat loss and changing climate have direct impacts on native species but can also interact with disease pathogens to influence wildlife communities. In the North American Great Plains, black‐tailed prairie dogs (Cynomys ludovicianus) are a keystone species that create important grassland habitat for numerous species and serve as prey for predators, but lethal control driven by agricultural conflict has severely reduced their abundance. Novel disease dynamics caused by epizootic plague (Yersinia pestis) within prairie dog colonies have further reduced prairie dog abundances, in turn destabilizing associated wildlife communities. We capitalized on a natural experiment, collecting data on prairie dog distributions, vegetation structure, avian abundance, and mesocarnivore and ungulate occupancy before (2015–2017) and after (2018–2019) a plague event in northeastern Wyoming, USA. Plague decimated black‐tailed prairie dog populations in what was then the largest extant colony complex, reducing colony cover in the focal area from more than 10,000 ha to less than 50 ha. We documented dramatic declines in mesocarnivore occupancy and raptor abundance post‐plague, with probability of occupancy or abundance approaching zero in species that rely on prairie dogs for a high proportion of their diet (e.g., ferruginous hawk [Buteo regalis], American badger [Taxidea taxus], and swift fox [Vulpes velox]). Following the plague outbreak, abnormally high precipitation in 2018 hastened vegetation recovery from prairie dog disturbance on colonies in which constant herbivory had formerly maintained shortgrass structure necessary for certain colony‐associates. As a result, we observed large shifts in avian communities on former prairie dog colonies, including near‐disappearance of mountain plovers (Charadrius montanus) and increases in mid‐grass associated songbirds (e.g., lark bunting [Calamospiza melanocorys]). Our research highlights how precipitation can interact with disease‐induced loss of a keystone species to induce drastic and rapid shifts in wildlife communities. Although grassland taxa have co‐evolved with high spatiotemporal variation, fragmentation of the remaining North American rangelands paired with higher‐than‐historical variability in climate and disease dynamics are likely to destabilize these systems in the future. [ABSTRACT FROM AUTHOR]

Keystone engineers are critical drivers of biodiversity throughout ecosystems worldwide. Within the North American Great Plains, the black‐tailed prairie dog is an imperiled ecosystem engineer and keystone species with well‐documented impacts on the flora and fauna of rangeland systems. However, because this species affects ecosystem structure and function in myriad ways (i.e., as a consumer, a prey resource, and a disturbance vector), it is unclear which effects are most impactful for any given prairie dog associate. We applied structural equation models (SEM) to disentangle direct and indirect effects of prairie dogs on multiple trophic levels (vegetation, arthropods, and birds) in the Thunder Basin National Grassland. Arthropods did not show any direct response to prairie dog occupation, but multiple bird species and vegetation parameters were directly affected. Surprisingly, the direct impact of prairie dogs on colony‐associated avifauna (Horned Lark [Eremophila alpestris] and Mountain Plover [Charadrius montanus]) had greater support than a mediated effect via vegetation structure, indicating that prairie dog disturbance may be greater than the sum of its parts in terms of impacts on localized vegetation structure. Overall, our models point to a combination of direct and indirect impacts of prairie dogs on associated vegetation, arthropods, and avifauna. The variation in these impacts highlights the importance of examining the various impacts of keystone engineers, as well as highlighting the diverse ways that black‐tailed prairie dogs are critical for the conservation of associated species. [ABSTRACT FROM AUTHOR]

North American sagebrush (Artemisia spp.)‐obligate birds are experiencing steep population declines due in part to increased disturbance, mainly human‐caused, across their range. At the eastern edge of the sagebrush steppe, this issue may potentially be exacerbated because of natural disturbance by black‐tailed prairie dogs (Cynomys ludovicianus). Our goal was to compare local and landscape models of habitat use by greater sage‐grouse (Centrocercus urophasianus), Brewer's sparrow (Spizella breweri), and sage thrasher (Oreoscoptes montanus) with models including effects of natural (i.e., prairie dog) and anthropogenic disturbance. We used a combination of field data collection, and state and national datasets for the Thunder Basin National Grassland, eastern Wyoming, USA, to understand the factors that influence lek attendance by sage‐grouse and habitat use by 2 passerines in this system. For all 3 species, models including big sagebrush (Artemisia tridentata) cover at local and landscape scales were the most competitive among univariate models, supporting the paradigm that sagebrush is key for these species. Models including anthropogenic disturbance (well density, road density) explained more variation than models of prairie dog disturbance alone for 2 of the 3 species, but long‐term disturbance by prairie dogs did reduce abundance of Brewer's sparrows. Although long‐term prairie dog disturbance has the potential to reduce sagebrush cover for sagebrush‐obligate birds, such events are likely rare because outbreaks of plague (Yersina pestis) and lethal control on borders with private land reduce prairie dog disturbance. Conversely, anthropogenic disturbance is slated to increase in this system, suggesting potentially accelerated declines for sagebrush birds into the future. © 2020 The Wildlife Society. Imperiled sagebrush songbirds and greater sage‐grouse are less likely to occupy disturbed habitat in northeastern Wyoming. Although these species are sensitive to both natural (prairie dog) and anthropogenic disturbance, the latter appears to play a larger role in habitat use in this region. [ABSTRACT FROM AUTHOR]

Ecotones, or transitional zones between ecosystems, are often hotspots for biodiversity and targets for conservation. Where the Great Plains meet the sagebrush (Artemisia spp.) steppe, an opportunity exists to conserve habitat for the two most imperiled avian guilds in North America, grassland and shrub‐steppe birds. This ecotone creates a unique challenge with respect to the management of disturbance processes, such as fire and grazing, because grassland and sagebrush‐shrubland birds respond quite dissimilarly to disturbance. To address this management challenge and maximize conservation opportunities, we examined the responses of grassland and sagebrush bird communities to disturbance at a grassland–sagebrush ecotone in northeast Wyoming, USA. Specifically, we surveyed bird communities on active black‐tailed prairie dog (Cynomys ludovicianus) colonies and burned areas, as well as on paired undisturbed points in 2016 and 2017. Bird community structure varied in response to both the presence and type of disturbance. Although alpha diversity of avian species was highest on undisturbed sites and burned areas, only prairie dog colonies provided breeding habitat for the imperiled shortgrass‐obligate mountain plover (Charadrius montanus), and species turnover (beta diversity) was greatest between on‐colony and off‐colony points. Furthermore, bird communities were shaped by both disturbance‐dependent (e.g., disturbance age) and disturbance‐independent (e.g., topography and soils) landscape features. Managers must balance the benefits of high species diversity in undisturbed sagebrush with habitat requirements of other imperiled species like the mountain plover. This may entail prioritizing the amount and distribution of disturbances in relation to population goals for species of conservation concern while simultaneously maintaining a mosaic of all three patch types in this landscape. [ABSTRACT FROM AUTHOR]