21 research outputs found

    Recognizing and integrating wildlife as Elwha restoration agents

    Get PDF
    Ecosystem restoration involving large dam removal spans large spatial extents, long time scales, and diverse societal constituencies. Restoration success requires collaboration among partner organizations. Success also can be facilitated by integrating components and processes of the ecosystem itself in restoration planning and practice. We review early and future roles of wildlife in restoration of valleys flooded by Elwha dams, with implications for dam removals on other rivers. Detecting early wildlife responses depended on baseline inventories prior to dam removal, followed by monitoring during and after dam removal. Pre-removal studies revealed patterns of small and mid-sized mammal occupancy, bear movement, amphibian occupancy, and avian distributions and species composition. In the few years since dam removal, wildlife colonization of exposed reservoir beds has been rapid, dominated by early successional and mobile species. Wildlife also perform important restoration functions, and contribute to all nine attributes defining restored ecosystems. This early in Elwha restoration, conspicuous wildlife functions include native seed dispersal to restoration sites, herbivore effects on revegetation, and organic matter dispersal to nutrient-poor sediments. In future decades, diverse wildlife also will help restore terrestrial-aquatic connections by dispersing nutrients from increasing salmon runs to riparian and terrestrial areas. Each of these wildlife roles is influenced by spatial distributions of pre-dam structural legacies and structures placed during active restoration efforts, particularly large woody debris. By placing these structures in locations and configurations that support wildlife functions, restoration planning and practice more effectively integrate wildlife in restoration. Benefits include increasing the rate of restoration progress and directing it along more desirable trajectories. In this way, the collaborative interdisciplinary approach in Elwha restoration can be expanded in future restoration projects to encompass active collaboration with the ecosystem itself

    Responses of river-dependent wildlife to dam removal, salmon restoration, and nutrient subsidies in the Elwha River Watershed, Olympic Peninsula, Washington

    Get PDF
    The ongoing removal of two hydroelectric dams from the Elwha River on Washington’s Olympic Peninsula provides an unprecedented opportunity to study the effects of dam removal and subsequent salmon restoration on river-dependent wildlife species. Salmon are widely known to distribute marine nutrients into freshwater systems, providing benefits to both riverine and upland wildlife communities through improved nutrient availability. We examined two species of river-dependent wildlife (river otter Lontra canadensis, and American dipper Cinclus mexicanus) to gather data on home range and seasonal movement patterns, body condition, and dietary contributions from marine-derived nutrients prior to and during dam removal. We radio-tracked ten river otters in the Elwha River and adjacent Salish Sea, and collected biological samples from all otters captured in the Elwha River as well as 246 dippers captured across four watersheds with varying qualities of salmon runs. We are using stable isotopes (C, N) to track marine derived nutrient contributions to the diets of otters and dippers, species that are both sensitive indicators of aquatic food web quality. In both species, stable-isotope ratios were more enriched in tissues from areas with intact salmon migrations, indicating greater consumption of salmon tissues and potential enrichment of invertebrate prey. In dippers, females breeding in areas with salmon migrations were in better condition and both sexes were more likely to occupy territories in fall. Adult condition patterns were more pronounced behind anthropogenic, compared to natural, obstructions. These patterns indicate that dams have sizeable individual level impacts on aquatic consumers and provide a valuable baseline to track the recovery of this watershed following completion of dam removal

    A Low-Cost GPS GSM/GPRS Telemetry System: Performance in Stationary Field Tests and Preliminary Data on Wild Otters (Lutra lutra)

    Get PDF
    Background: Despite the increasing worldwide use of global positioning system (GPS) telemetry in wildlife research, it has never been tested on any freshwater diving animal or in the peculiar conditions of the riparian habitat, despite this latter being one of the most important habitat types for many animal taxa. Moreover, in most cases, the GPS devices used have been commercial and expensive, limiting their use in low-budget projects. Methodology/Principal Findings: We have developed a low-cost, easily constructed GPS GSM/GPRS (Global System for Mobile Communications/General Packet Radio Service) and examined its performance in stationary tests, by assessing the influence of different habitat types, including the riparian, as well as water submersion and certain climatic and environmental variables on GPS fix-success rate and accuracy. We then tested the GPS on wild diving animals, applying it, for the first time, to an otter species (Lutra lutra). The rate of locations acquired during the stationary tests reached 63.2%, with an average location error of 8.94 m (SD = 8.55). GPS performance in riparian habitats was principally affected by water submersion and secondarily by GPS inclination and position within the riverbed. Temporal and spatial correlations of location estimates accounted for some variation in the data sets. GPS-tagged otters also provided accurate locations and an even higher GPS fix-success rate (68.2%). Conclusions/Significance: Our results suggest that GPS telemetry is reliably applicable to riparian and even divin

    Step by step: reconstruction of terrestrial animal movement paths by dead-reckoning

    Get PDF
    Background: Research on wild animal ecology is increasingly employing GPS telemetry in order to determine animal movement. However, GPS systems record position intermittently, providing no information on latent position or track tortuosity. High frequency GPS have high power requirements, which necessitates large batteries (often effectively precluding their use on small animals) or reduced deployment duration. Dead-reckoning is an alternative approach which has the potential to ‘fill in the gaps’ between less resolute forms of telemetry without incurring the power costs. However, although this method has been used in aquatic environments, no explicit demonstration of terrestrial dead-reckoning has been presented.Results: We perform a simple validation experiment to assess the rate of error accumulation in terrestrial dead-reckoning. In addition, examples of successful implementation of dead-reckoning are given using data from the domestic dog Canus lupus, horse Equus ferus, cow Bos taurus and wild badger Meles meles.Conclusions: This study documents how terrestrial dead-reckoning can be undertaken, describing derivation of heading from tri-axial accelerometer and tri-axial magnetometer data, correction for hard and soft iron distortions on the magnetometer output, and presenting a novel correction procedure to marry dead-reckoned paths to ground-truthed positions. This study is the first explicit demonstration of terrestrial dead-reckoning, which provides a workable method of deriving the paths of animals on a step-by-step scale. The wider implications of this method for the understanding of animal movement ecology are discussed

    SNAPSHOT USA 2020: A second coordinated national camera trap survey of the United States during the COVID-19 pandemic

    Get PDF
    Managing wildlife populations in the face of global change requires regular data on the abundance and distribution of wild animals, but acquiring these over appropriate spatial scales in a sustainable way has proven challenging. Here we present the data from Snapshot USA 2020, a second annual national mammal survey of the USA. This project involved 152 scientists setting camera traps in a standardized protocol at 1485 locations across 103 arrays in 43 states for a total of 52,710 trap-nights of survey effort. Most (58) of these arrays were also sampled during the same months (September and October) in 2019, providing a direct comparison of animal populations in 2 years that includes data from both during and before the COVID-19 pandemic. All data were managed by the eMammal system, with all species identifications checked by at least two reviewers. In total, we recorded 117,415 detections of 78 species of wild mammals, 9236 detections of at least 43 species of birds, 15,851 detections of six domestic animals and 23,825 detections of humans or their vehicles. Spatial differences across arrays explained more variation in the relative abundance than temporal variation across years for all 38 species modeled, although there are examples of significant site-level differences among years for many species. Temporal results show how species allocate their time and can be used to study species interactions, including between humans and wildlife. These data provide a snapshot of the mammal community of the USA for 2020 and will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, and the impacts of species interactions on daily activity patterns. There are no copyright restrictions, and please cite this paper when using these data, or a subset of these data, for publication
    corecore