32 research outputs found

    Seasonal habitat selection of the North American porcupine (Erethizon dorsatum) in a coastal dune forest

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    Wildlife-habitat relationship studies are important for understanding the factors that determine where species occur in space and time. Habitat selection by generalist species should be studied on fine spatial and temporal scales to avoid masking important differences between seasons, localities, or orders of selection. I conducted the first study of habitat use and general ecology of North American porcupines (Erethizon dorsatum) in a coastal dune environment. Specifically, I assessed changes in body mass, home range size, and habitat selection in relation to the potential for seasonal nutritional and survival bottlenecks as reported elsewhere. Although they are considered generalists, porcupines have adapted specialized feeding strategies allowing them to survive periods of harsh weather and low food availability. In this study, porcupines were selective in their habitat use at the home-range and within-home-range scales during both summer and winter. In summer, porcupines selected willow-dominated swales, marshes, and fruit trees, and during the winter they selected coastal scrub, dunes, and conifer forests. These changes were most likely driven by forage availability, leading to dramatic body mass loss between summer and winter. On average, females lost 7.5% of their body mass and males lost 17.8%. Further, four out of five mortalities occurred during the winter, which is consistent with nutritional decline. Porcupines had larger home ranges during the summer than the winter by approximately 31%. These spatiotemporal changes are similar to those reported elsewhere, indicating that similar strategies are used by this habitat generalist across its range

    Distribution of the North American Porcupine (Erethizon dorsatum) in Northern California

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    Western Wildlife 4:17–28, 2017: The North American Porcupine (Erethizon dorsatum) is one of the most widely distributed mammals in North America, but recent reports have suggested declines in parts of its range in the West. In California, little is known about the historical or current status of the porcupine, and maps of its distribution conflict considerably. Nevertheless, the species is of interest to natural resource managers. For much of the 1900s, foresters and others primarily treated porcupines as pests because of the undesirable damage they inflict feeding on trees and gnawing on manmade items in search of salt. More recently, porcupines have been recognized for their role in promoting forest structure and diversity, and as potential prey for the Fisher (Pekania pennanti). We collected records of porcupine occurrence in the northern part of California since the beginning of the 20th Century, relying on government and private databases, reports from the public, and other sources. These records confirm that porcupines may occur in most major regions and habitat types across northern California, in contrast to many published range maps. The contemporary distribution of porcupines in the state most closely resembles the California Wildlife Habitat Relationships System (CWHR) range map, which is based on projections of suitable habitat. We are unable to offer deeper insight into trends of abundance and possible changes in distribution because these records are likely spatiotemporally correlated with observer effort. This work is a first step and we recommend that a broader statewide effort be conducted to better understand the distribution, abundance, and ecology of North American Porcupines in California. See below or click here to view data

    The rapid rise of next-generation natural history

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    Many ecologists have lamented the demise of natural history and have attributed this decline to a misguided view that natural history is outdated and unscientific. Although there is a perception that the focus in ecology and conservation have shifted away from descriptive natural history research and training toward hypothetico-deductive research, we argue that natural history has entered a new phase that we call “next-generation natural history.” This renaissance of natural history is characterized by technological and statistical advances that aid in collecting detailed observations systematically over broad spatial and temporal extents. The technological advances that have increased exponentially in the last decade include electronic sensors such as camera-traps and acoustic recorders, aircraft- and satellite-based remote sensing, animal-borne biologgers, genetics and genomics methods, and community science programs. Advances in statistics and computation have aided in analyzing a growing quantity of observations to reveal patterns in nature. These robust next-generation natural history datasets have transformed the anecdotal perception of natural history observations into systematically collected observations that collectively constitute the foundation for hypothetico-deductive research and can be leveraged and applied to conservation and management. These advances are encouraging scientists to conduct and embrace detailed descriptions of nature that remain a critically important component of the scientific endeavor. Finally, these next-generation natural history observations are engaging scientists and non-scientists alike with new documentations of the wonders of nature. Thus, we celebrate next-generation natural history for encouraging people to experience nature directly

    SNAPSHOT USA 2019 : a coordinated national camera trap survey of the United States

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    This article is protected by copyright. All rights reserved.With the accelerating pace of global change, it is imperative that we obtain rapid inventories of the status and distribution of wildlife for ecological inferences and conservation planning. To address this challenge, we launched the SNAPSHOT USA project, a collaborative survey of terrestrial wildlife populations using camera traps across the United States. For our first annual survey, we compiled data across all 50 states during a 14-week period (17 August - 24 November of 2019). We sampled wildlife at 1509 camera trap sites from 110 camera trap arrays covering 12 different ecoregions across four development zones. This effort resulted in 166,036 unique detections of 83 species of mammals and 17 species of birds. All images were processed through the Smithsonian's eMammal camera trap data repository and included an expert review phase to ensure taxonomic accuracy of data, resulting in each picture being reviewed at least twice. The results represent a timely and standardized camera trap survey of the USA. All of the 2019 survey data are made available herein. We are currently repeating surveys in fall 2020, opening up the opportunity to other institutions and cooperators to expand coverage of all the urban-wild gradients and ecophysiographic regions of the country. Future data will be available as the database is updated at eMammal.si.edu/snapshot-usa, as well as future data paper submissions. These data will be useful for local and macroecological research including the examination of community assembly, effects of environmental and anthropogenic landscape variables, effects of fragmentation and extinction debt dynamics, as well as species-specific population dynamics and conservation action plans. There are no copyright restrictions; please cite this paper when using the data for publication.Publisher PDFPeer reviewe

    Mammal responses to global changes in human activity vary by trophic group and landscape

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    Wildlife must adapt to human presence to survive in the Anthropocene, so it is critical to understand species responses to humans in different contexts. We used camera trapping as a lens to view mammal responses to changes in human activity during the COVID-19 pandemic. Across 163 species sampled in 102 projects around the world, changes in the amount and timing of animal activity varied widely. Under higher human activity, mammals were less active in undeveloped areas but unexpectedly more active in developed areas while exhibiting greater nocturnality. Carnivores were most sensitive, showing the strongest decreases in activity and greatest increases in nocturnality. Wildlife managers must consider how habituation and uneven sensitivity across species may cause fundamental differences in human–wildlife interactions along gradients of human influence.Peer reviewe

    Distribution of the North American Porcupine (Erethizon dorsatum) in Northern California Appendix

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    Western Wildlife 4:17–28, 2017: The North American Porcupine (Erethizon dorsatum) is one of the most widely distributed mammals in North America, but recent reports have suggested declines in parts of its range in the West. In California, we know little about porcupines’ historical or current status; maps of porcupine distribution conflict considerably. Nevertheless, the species is of interest to natural resource managers. For much of the 1900s, foresters and others primarily treated porcupines as pests because of the undesirable damage they inflict by feeding on trees and gnawing on manmade items in search of salt. More recently, porcupines have been recognized for their role as engineers, contributing important structure and diversity to forest ecosystems, and as prey for the imperiled Fisher (Pekania pennanti). We collected records of porcupine occurrence in the northern half of California since the beginning of the twentieth century, relying on government and private databases, reports from the public, and other sources. These records confirm porcupine distribution in most major regions and habitat types across northern California, in contrast to many published range maps, and most closely resemble the range map based on projections of suitable habitat developed by the California Wildlife Habitat Relationships System (CWHR). We are unable to offer deeper insight into trends of abundance and possible changes in distribution because these records are likely spatiotemporally correlated with observer effort. This work is a first step in what must be a broader statewide effort, and we encourage further research on the distribution, abundance, and ecology of porcupines in California. The data provided here consists of 363 unique records of porcupine locations in northern California spanning the years 1908 to 2016. Records were obtained from a participant science project (porcufinder.com); internal California Department of Fish & Wildlife records; the California Roadkill Observation System (CROS); internal U.S. Forest Service Records; a study by former HSU Wildlife professor Charles Yocom; iNaturalist; and the Global Biodiversity Information Facility. The second tab includes descriptions of each column of the data, and additional information is available in the (forthcoming) publication. Read article here

    Long-term monitoring in transition: Resolving spatial mismatch and integrating multistate occupancy data

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    The success of long-term wildlife monitoring programs can be influenced by many factors and study designs often represent compromises between spatial scales and costs. Adaptive monitoring programs can iteratively manage this tension by adopting new cost-efficient technologies, which can provide projects the opportunity to reallocate costs to address new hypotheses, adapt to changing ecological conditions, or adjust sampling scale or resolution. If there is interest in longer time series of monitoring data, methodological transitions may necessitate integrated models to link newer data with historical data. However, data integration can be difficult if spatial or temporal scales are mismatched. Here, we develop an integrated multistate site-occupancy model and resolve sample unit spatial mismatch to link datasets from two northern spotted owl (Strix occidentalis caurina) monitoring schemes that broadly overlapped during a methodological transition. The first dataset was obtained from a decades-long spotted owl monitoring program using call-playback and mark-resight surveys on historical territories of varying size and shape. This monitoring program has recently transitioned to passive acoustic monitoring of randomly selected 5-km2 hexagons over larger spatial extents. Both monitoring datasets overlapped with areas in which barred owl (Strix varia), an invasive competitor that has played an important role in northern spotted owl declines, were being removed experimentally. Reconciling spatial mismatch substantially increased the representation of the call-playback dataset and integrating the two datasets increased precision of spotted owl use and paired occupancy estimates relative to single dataset estimates. Estimates of spotted owl pair occupancy across the study area were lower than previous territory-based estimates based on call-playback surveys. Our integrated model further showed that a concurrent barred owl removal experiment increased landscape use and site occupancy by pairs of spotted owls. Our empirical application of an integrated modelling approach demonstrates a useful analytical framework for long-term monitoring efforts undergoing methodological transitions (e.g. mark-recapture to non-invasive population monitoring). This framework allows monitoring programs to maintain continuity of monitoring objectives across methodological transitions, rigorously incorporate previous findings, and adaptively respond to changing ecological conditions

    Data Repository for North American Porcupine Distribution in the Pacific Northwest and Evaluation of a Non-Invasive Monitoring Technique

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    North American Porcupines (Erethizon dorsatum) have a broad geographic distribution across much of the continent, but recent evidence suggests that their populations may be declining in some areas, including the Pacific Northwest. Estimating baseline historical and contemporary distributions of Porcupines is necessary for initiating monitoring efforts and, if necessary, informing strategic conservation actions. We compiled 1905 occurrence records of Porcupines in Washington, Oregon, and northern California from 1908 to 2018. Using maximum entropy modeling (Maxent), we created historical and contemporary distribution models based on Porcupine records from 1981–2010 and 2012–2018, respectively, to match the temporal scale of available environmental predictor layers and suspected onset of the decline. Our models suggested a recent shift in the occupied environmental niche of Porcupines in the Pacific Northwest away from forested areas and towards desert scrub and grassland vegetation communities. In addition, we tested a non-invasive survey method for determining Porcupine presence and monitoring their status over time. Our trials suggested that sodium-soaked wood blocks may provide an inexpensive and minimally invasive technique to detect Porcupines, but further testing is needed to understand its effectiveness and limitations. Corresponding manuscript citation: Appel, C. L., K. M. Moriarty, S. M. Matthews, D. S. Green, S. Anderson, E. King, J. S. Yaeger, J. Brown, C. Bortot, and W. T. Bean. 2021. North American Porcupine distribution in the Pacific Northwest and evaluation of a non-invasive monitoring technique. Northwestern Naturalist 102:9–29

    Regulation and Function of Epithelial Secreted Phospholipase A2 Group X in Asthma

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    RationaleIndirect airway hyperresponsiveness (AHR) is a fundamental feature of asthma that is manifest as exercise-induced bronchoconstriction (EIB). Secreted phospholipase A2 group X (sPLA2-X) plays a key role in regulating eicosanoid formation and the development of inflammation and AHR in murine models.ObjectivesWe sought to examine sPLA2-X in the airway epithelium and airway wall of patients with asthma, the relationship to AHR in humans, and the regulation and function of sPLA2-X within the epithelium.MethodsWe precisely phenotyped 34 patients with asthma (19 with and 15 without EIB) and 10 normal control subjects to examine in vivo differences in epithelial gene expression, quantitative morphometry of endobronchial biopsies, and levels of secreted protein. The regulation of sPLA2-X gene (PLA2G10) expression was examined in primary airway epithelial cell cultures. The function of epithelial sPLA2-X in eicosanoid formation was examined using PLA2 inhibitors and murine tracheal epithelial cells with Pla2g10 deletion.Measurements and main resultsWe found that sPLA2-X protein is increased in the airways of patients with asthma and that epithelial-derived sPLA2-X may be increased in association with indirect AHR. The expression of sPLA2-X increases during in vitro epithelial differentiation; is regulated by inflammatory signals including tumor necrosis factor, IL-13, and IL-17; and is both secreted from the epithelium and directly participates in the release of arachidonic acid by epithelial cells.ConclusionsThese data reveal a relationship between epithelial-derived sPLA2-X and indirect AHR in asthma and that sPLA2-X serves as an epithelial regulator of inflammatory eicosanoid formation. Therapies targeting epithelial sPLA2-X may be useful in asthma
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