14 research outputs found
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Spatial and temporal movement patterns of wintering Dunlin (Calidris alpina) and Killdeer (Charadrius vociferus) in the Willamette Valley, Oregon
Avian movement behavior provides insight on patterns of regional and local fidelity, habitat and resource requirements, the scale at which individuals perceive the landscape, and the relative influence of the spatial array of resources. Shorebirds (suborder: Charadrii) are a diverse and mobile group of wetland associated species. Large numbers of shorebirds utilize seasonally flooded wetland habitats in the Willamette Valley of northwest Oregon; however, there is little information on fidelity and movements of birds in the region or at other inland sites. Thus, we quantified winter fidelity and movement patterns of radio-tagged Dunlin (Calidris alpina) and Killdeer (Charadrius vociferus) in the Willamette Valley in 1998-1999 and 1999-2000. Prior to field telemetry, we evaluated use of a leg-loop harness design for attachment of radio-transmitters. Comparisons between captive Western Sandpipers (Calidris mauri) fitted with a harness package and a control group indicated no significant differences in behavior. In addition, observations of wild Killdeer and Dunlin indicated prolonged harness retention and no adverse effects on behavior. Therefore, we determined that the modified harness design was a suitable method for attachment of transmitters to shorebirds. Monitoring of radio-tagged Dunlin and Killdeer indicated interspecific differences in regional fidelity and residency patterns. Dunlin exhibited a high degree of regional fidelity and in most cases remained within the Valley for the duration of the winter. In contrast, Killdeer departed the study area throughout the winter and the population segment monitored was composed of winter residents (63%), winter transients (26%) and year-round resident breeders (11%). Dunlin were highly mobile with frequent movements up to 30 km from roost sites. Among seasons, Dunlin differed significantly in distance traveled, mean distance from capture site, and home range size. All were greatest during late winter. In comparison, the scale of Killdeer movements was much smaller, with no seasonal differences in movements. Results also suggested that resident Killdeer were more sedentary than migrants during the winter months. At a local scale, individuals of both species occurred predominantly in agricultural habitats and exhibited low degrees of fidelity to specific fields, with the exception that Dunlin frequently returned to certain roost sites. On a daily basis, movements of both Dunlin and Killdeer were most pronounced during crepuscular periods. Findings provide insight on the fidelity and winter movements of shorebirds, as well provide insight as to the functional connectivity of shorebird habitats in the Willamette Valley
Comparing imaging, acoustics, and radar to monitor Leach’s storm-petrel colonies
Seabirds are integral components of marine ecosystems and, with many populations globally threatened, there is a critical need for effective and scalable seabird monitoring strategies. Many seabird species nest in burrows, which can make traditional monitoring methods costly, infeasible, or damaging to nesting habitats. Traditional burrow occupancy surveys, where possible, can occur infrequently and therefore lead to an incomplete understanding of population trends. For example, in Oregon, during the last three decades there have been large changes in the abundance of Leach’s storm-petrels (Hydrobates leucorhoa), which included drastic declines at some colonies. Unfortunately, traditional monitoring failed to capture the timing and magnitude of change, limiting managers’ ability to determine causes of the decline and curtailing management options. New, easily repeatable methods of quantifying relative abundance are needed. For this study, we tested three methods of remote monitoring: passive acoustic monitoring, time-lapse cameras, and radar. Abundance indices derived from acoustics and imagery: call rates, acoustic energy, and counts were significantly related to traditional estimates of burrow occupancy of Leach’s storm-petrels. Due to sampling limitations, we were unable to compare radar to burrow occupancy. Image counts were significantly correlated with all other indices, including radar, while indices derived from acoustics and radar were not correlated. Acoustic data likely reflect different aspects of the population and hold the potential for the further development of indices to disentangle phenology, attendance of breeding birds, and reproductive success. We found that image counts are comparable with standard methods (e.g., radar) in producing annual abundance indices. We recommend that managers consider a sampling scheme that incorporates both acoustics and imaging, but for sites inaccessible to humans, radar remains the sole option. Implementation of acoustic and camera based monitoring programs will provide much needed information for a vulnerable group of seabirds
Applying extracellular vesicles based therapeutics in clinical trials - an ISEV position paper
Extracellular vesicles (EVs), such as exosomes and microvesicles, are released by different cell types and participate in physiological and pathophysiological processes. EVs mediate intercellular communication as cell-derived extracellular signalling organelles that transmit specific information from their cell of origin to their target cells. As a result of these properties, EVs of defined cell types may serve as novel tools for various therapeutic approaches, including (a) anti-tumour therapy, (b) pathogen vaccination, (c) immune-modulatory and regenerative therapies and (d) drug delivery. The translation of EVs into clinical therapies requires the categorization of EV-based therapeutics in compliance with existing regulatory frameworks. As the classification defines subsequent requirements for manufacturing, quality control and clinical investigation, it is of major importance to define whether EVs are considered the active drug components or primarily serve as drug delivery vehicles. For an effective and particularly safe translation of EV-based therapies into clinical practice, a high level of cooperation between researchers, clinicians and competent authorities is essential. In this position statement, basic and clinical scientists, as members of the International Society for Extracellular Vesicles (ISEV) and of the European Cooperation in Science and Technology (COST) program of the European Union, namely European Network on Microvesicles and Exosomes in Health and Disease (ME-HaD), summarize recent developments and the current knowledge of EV-based therapies. Aspects of safety and regulatory requirements that must be considered for pharmaceutical manufacturing and clinical application are highlighted. Production and quality control processes are discussed. Strategies to promote the therapeutic application of EVs in future clinical studies are addresse
Movements of Wintering Dunlin \u3ci\u3eCalidris alpina\u3c/i\u3e and Changing Habitat Availability in an Agricultural Wetland Landscape
Few studies have assessed how the dynamics of wetland bird movements relate to changing resource availability, particularly at more than one spatial scale. Within western Oregon’s Williamette Valley, we examined winter resident Dunlin Calidris alpina movements in relation to a decrease in availability of preferred shorebird foraging habitat from early to late winter of 1999–2000. By tracking movements of 15 (early winter) and 12 (late winter) radiomarked individuals, we calculated home ranges and characterized presence/absence of a preference for shorebird foraging habitat during each winter period. Between periods, we compared: (1) percentage of shorebird habitat in home ranges to its availability in the landscape (regional preference), (2) percentage of radio locations in shorebird habitat to its availability within home ranges (local preference) and (3) relative use of roost sites. Concurrent with a 75% decrease in available shorebird habitat from early to late winter, average home range sizes increased by a factor of 3.8. At a regional scale, home ranges in early winter included a significantly greater percentage of shorebird foraging habitat than was available in the wider landscape. However, by late winter, the percent of shorebird habitat in home ranges did not match availability in the landscape. At the local scale, for both winter periods Dunlin were located in shorebird foraging habitat more often than expected given availability of habitat within home ranges [Correction added after online publication 23 May 2008: sentence amended]. An increase in the number of roosts used from early to late winter implies possible reliance on additional sites in late winter for foraging opportunities. Results suggest that wet, unvegetated habitat is sought by Dunlin throughout winter, but individuals could not select home ranges in late winter that fully compensated for seasonal loss of habitat
Capture of Breeding and Wintering Shorebirds with Leg-Hold Noose-Mats
Development of effective trapping techniques is important for conservation efforts, as marking and subsequent monitoring of individuals is necessary to obtain accurate estimates of demography, movements, and habitat use. We describe a leg-hold noose-mat trap for capturing breeding and nonbreeding shorebirds. Using this method, we trapped 50 Piping Plovers (Charadrius melodus), 2258 Snowy Plovers (C. alexandrinus), 38 Killdeers (C. vociferus), and 64 Dunlins (Calidris alpina) in the western and southern United States. The trap was lightweight, making it easy to transport and set up. It was effective on unvegetated substrates at both coastal and inland sites and could be modified for a variety of habitats. Furthermore, this trap allowed researchers to target specific groups of birds including territorial individuals. Easy removal of birds from traps minimized handling time, stress, and injury
Evaluating potential effects of solar power facilities on wildlife from an animal behavior perspective
Solar power is a renewable energy source with great potential to help meet increasing global energy demands and reduce our reliance on fossil fuels. However, research is scarce on how solar facilities affect wildlife. With input from professionals in ecology, conservation, and energy, we conducted a research-prioritization process and identified key questions needed to better understand impacts of solar facilities on wildlife. We focused on animal behavior, which can be used to identify population responses before mortality or other fitness consequences are documented. Behavioral studies can also offer approaches to understand the mechanisms leading to negative interactions (e.g., collision, singeing, avoidance) and provide insight into mitigating effects. Here, we review how behavioral responses to solar facilities, including perception, movement, habitat use, and interspecific interactions are priority research areas. Addressing these themes will lead to a more comprehensive understanding of the effects of solar power on wildlife and guide future mitigation
Genetic identification of avian samples recovered from solar energy installations.
Renewable energy production and development will drastically affect how we meet global energy demands, while simultaneously reducing the impact of climate change. Although the possible effects of renewable energy production (mainly from solar- and wind-energy facilities) on wildlife have been explored, knowledge gaps still exist, and collecting data from wildlife remains (when negative interactions occur) at energy installations can act as a first step regarding the study of species and communities interacting with facilities. In the case of avian species, samples can be collected relatively easily (as compared to other sampling methods), but may only be able to be identified when morphological characteristics are diagnostic for a species. Therefore, many samples that appear as partial remains, or "feather spots"-known to be of avian origin but not readily assignable to species via morphology-may remain unidentified, reducing the efficiency of sample collection and the accuracy of patterns observed. To obtain data from these samples and ensure their identification and inclusion in subsequent analyses, we applied, for the first time, a DNA barcoding approach that uses mitochondrial genetic data to identify unknown avian samples collected at solar facilities to species. We also verified and compared identifications obtained by our genetic method to traditional morphological identifications using a blind test, and discuss discrepancies observed. Our results suggest that this genetic tool can be used to verify, correct, and supplement identifications made in the field and can produce data that allow accurate comparisons of avian interactions across facilities, locations, or technology types. We recommend implementing this genetic approach to ensure that unknown samples collected are efficiently identified and contribute to a better understanding of wildlife impacts at renewable energy projects
Evaluating potential effects of solar power facilities on wildlife from an animal behavior perspective
Solar power is a renewable energy source with great potential to helpmeet increasing global energy demands and reduce our reliance on fossilfuels. However, research is scarce on how solar facilities affect wildlife.With input from professionals in ecology, conservation, and energy, weconducted a research-prioritization process and identified key questionsneeded to better understand impacts of solar facilities on wildlife. Wefocused on animal behavior, which can be used to identify populationresponses before mortality or other fitness consequences aredocumented. Behavioral studies can also offer approaches to understandthe mechanisms leading to negative interactions (e.g., collision,singeing, avoidance) and provide insight into mitigating effects. Here, wereview how behavioral responses to solar facilities, including perception,movement, habitat use, and interspecific interactions are priorityresearch areas. Addressing these themes will lead to a morecomprehensive understanding of the effects of solar power on wildlifeand guide future mitigation
Vulnerability of avian populations to renewable energy production
Renewable energy production can kill individual birds, but little is known about how it affects avian populations. We assessed the vulnerability of populations for 23 priority bird species killed at wind and solar facilities in California, USA. Bayesian hierarchical models suggested that 48% of these species were vulnerable to population-level effects from added fatalities caused by renewables and other sources. Effects of renewables extended far beyond the location of energy production to impact bird populations in distant regions across continental migration networks. Populations of species associated with grasslands where turbines were located were most vulnerable to wind. Populations of nocturnal migrant species were most vulnerable to solar, despite not typically being associated with deserts where the solar facilities we evaluated were located. Our findings indicate that addressing declines of North American bird populations requires consideration of the effects of renewables and other anthropogenic threats on both nearby and distant populations of vulnerable species