241 research outputs found

    Landscape controls on fuel moisture variability in fire-prone heathland and peatland landscapes

    Get PDF
    Background: Cross-landscape fuel moisture content is highly variable but not considered in existing fire danger assessments. Capturing fuel moisture complexity and its associated controls is critical for understanding wildfire behavior and danger in emerging fire-prone environments that are influenced by local heterogeneity. This is particularly true for temperate heathland and peatland landscapes that exhibit spatial differences in the vulnerability of their globally important carbon stores to wildfire. Here we quantified the range of variability in the live and dead fuel moisture of Calluna vulgaris across a temperate fire-prone landscape through an intensive fuel moisture sampling campaign conducted in the North Yorkshire Moors, UK. We also evaluated the landscape (soil texture, canopy age, aspect, and slope) and micrometeorological (temperature, relative humidity, vapor pressure deficit, and windspeed) drivers of landscape fuel moisture variability for temperate heathlands and peatlands for the first time. Results: We observed high cross-landscape fuel moisture variation, which created a spatial discontinuity in the availability of live fuels for wildfire spread (fuel moisture < 65%) and vulnerability of the organic layer to smoldering combustion (fuel moisture < 250%). This heterogeneity was most important in spring, which is also the peak wildfire season in these temperate ecosystems. Landscape and micrometeorological factors explained up to 72% of spatial fuel moisture variation and were season- and fuel-layer-dependent. Landscape factors predominantly controlled spatial fuel moisture content beyond modifying local micrometeorology. Accounting for direct landscape–fuel moisture relationships could improve fuel moisture estimates, as existing estimates derived solely from micrometeorological observations will exclude the underlying influence of landscape characteristics. We hypothesize that differences in soil texture, canopy age, and aspect play important roles across the fuel layers examined, with the main differences in processes arising between live, dead, and surface/ground fuels. We also highlight the critical role of fuel phenology in assessing landscape fuel moisture variations in temperate environments. Conclusions: Understanding the mechanisms driving fuel moisture variability opens opportunities to develop locally robust fuel models for input into wildfire danger rating systems, adding versatility to wildfire danger assessments as a management tool

    Adult bobcat (\u3ci\u3eLynx rufus\u3c/i\u3e) habitat selection in a longleaf pine savanna

    Get PDF
    Background: Pine savannas are primarily managed with frequent prescribed fire (≤ 3 years) to promote diversity of flora and fauna, and to maintain open, park-like conditions needed by species such as the endangered red-cockaded woodpecker (Picoides borealis). However, a knowledge gap exists in our understanding of bobcat (Lynx rufus) habitat selection in longleaf pine savannas and research is warranted to direct our future management decisions. Methods: We examined bobcat habitat selection in a pine savanna managed with frequent fires at two spatial scales (i.e., study area boundary [hereafter, landscape scale]) and annual area of use [95% kernel density; local scale]), and assessed effects of prescribed fire on bobcat habitat selection. Specifically, we monitored 45 bobcats (16 males and 29 females) during 2001–2007. Results: We found differential habitat selection by sex. At the landscape scale, female bobcats were closer to mixed pine-hardwoods, young pine, and secondary roads, but farther from mature pine and hardwoods stands relative to males. We found no difference in selection of agriculture, shrub-scrub, and primary roads between sexes. At the annual area of use scale, female bobcats were closer to secondary roads, but farther from agriculture and shrub-scrub relative to males. We found no difference in selection of mature pine, mixed pine-hardwoods, hardwoods, young pine, and primary roads between sexes. Bobcats primarily selected for stands burned ≤ 1.1 years post-fire. Conclusions: Our results show that bobcats exploit a broad range of habitat types in pine landscapes managed with frequent fire and commonly use recently burned stands (≤ 1.1 year post-fire), suggesting prey in many areas of this system are at risk of bobcat predation. Additionally, we suggest land managers consider scale of selection by bobcats when developing habitat management strategies

    Habitat Characteristics of Eastern Wild Turkey Nest and Ground-roost Sites in 2 Longleaf Pine Forests

    Get PDF
    Managing and restoring longleaf pine forests throughout the Southeast is a conservation priority. Prescribed fire is an integral part of these activities, as it is the primary means of controlling hardwood encroachment and maintaining native groundcover. Nest site and preflight brood groundroost site selection of eastern wild turkeys (Meleagris gallopavo silvestris) has not been well studied in longleaf pine systems. Therefore, we determined habitat characteristics associated with wild turkey nests and ground-roosts in 2 longleaf pine forests in southwestern Georgia. We radio-tagged 45 female turkeys and evaluated habitat characteristics associated with 84 nests and 51 ground-roosts during the 2011–2013 nesting seasons. Nests were located farther from mature pine and mature pine-hardwood stands and closer to shrub/scrub habitats than expected. Nests were also negatively associated with percent canopy closure and positively associated with percent woody ground cover and vegetation height. Ground-roosts were closer to mature pine-hardwood stands and open water than were random sites. We suggest that management of longleaf pine forests should focus on maintaining open-canopied forests with adequate understory vegetation to serve as nesting and brood-rearing cover. Our findings suggest that frequent prescribed fire (≤ 2 years), when the management goal is to optimize restoration of longleaf ecosystems, is conducive to maintaining wild turkey populations

    Survival and cause-specific mortality of female eastern wild turkeys in two frequently-burned longleaf pine savannas

    Get PDF
    Longleaf pine savannas have declined throughout the southeastern United States due to land-use change. Fortunately, natural resource professionals are currently restoring these ecologically and economically important savannas. Although efforts are underway to restore longleaf pine savannas, little information exists on female eastern wild turkey Meleagris gallopavo silvestris population dynamics in these systems. Therefore, we evaluated survival and cause-specific mortality of female eastern wild turkeys in two longleaf pine savannas in southwestern Georgia. We radio-marked 126 female wild turkeys during 2010–2013 and monitored their survival; 66 (52.4%) radio-marked females died during the study. We estimated causes of death for 37 mortality events with predation serving as the leading known cause of mortality, with 35.1% of mortalities attributed to mesocarnivore predation (e.g., bobcat Lynx rufus, coyote Canis latrans, and gray fox Urocyon cinereoargenteus) and 18.9% to great-horned owl Bubo virginianus predation. One female (2.7%) was hit by a vehicle. Seasonal survival estimates varied from a high during fall (Ŝ = 0.94; 95% CI: 0.86–1.00) to a low during spring (Ŝ = 0.76; 95% CI: 0.68–0.87). Survival of incubating females was 0.82 (95% CI: 0.71–0.93) and survival of nonincubating females was 0.67 (95% CI: 0.52–0.87). Annual survival was 0.55 (95% CI: 0.44–0.67). To ensure sustainable wild turkey populations in longleaf pine savannas, we suggest managers monitor relationships between survival and population productivity

    Eastern wild turkey nest site selection in two frequently burned pine savannas

    Get PDF
    Introduction: Reproductive success is a critical factor affecting avian demographics and can be influenced by many factors including nesting chronology, predation risk, and fine-scale nest site selection. Methods: We modeled the relative influences of habitat-related covariates at six spatial scales (nest site: 15-, 40-, 80-, 120-, 160-, and 200-m radii) on Eastern wild turkey (Meleagris gallopavo silvestris) nest site selection in two pine savannas managed by frequent prescribed fire (≤3 years) in southwestern Georgia during 2011–2013. Results: Nest site (15-m scale) habitat metrics (mean visual obstruction [cm] and canopy closure [%]) had the greatest influence on nest site selection relative to covariates measured at larger spatial scales. Scaled odds ratios suggested that nests were 26.8 % more likely to occur for every 10 cm increase in mean vegetation height with a range of 7.5 to 150.0 cm and 18.5 % less likely to occur for every 10 % increase in canopy closure with a range from 0.0 to 97.8 %. Total ground cover, canopy closure, edge density, and percent land cover type (e.g., mature pine, mixed pine/hardwood, shrub/scrub) had minimal influence on nest site selection. Conclusions: Management of pine savannas for turkey nest sites should focus on creating early-successional vegetation to conceal nests from potential predators. Additionally, we suggest that future studies consider evaluating the influence of spatial scale on turkey nest site selection

    Survival and cause-specific mortality of female eastern wild turkeys in two frequently-burned longleaf pine savannas

    Get PDF
    Longleaf pine savannas have declined throughout the southeastern United States due to land-use change. Fortunately, natural resource professionals are currently restoring these ecologically and economically important savannas. Although efforts are underway to restore longleaf pine savannas, little information exists on female eastern wild turkey Meleagris gallopavo silvestris population dynamics in these systems. Therefore, we evaluated survival and cause-specific mortality of female eastern wild turkeys in two longleaf pine savannas in southwestern Georgia. We radio-marked 126 female wild turkeys during 2010–2013 and monitored their survival; 66 (52.4%) radio-marked females died during the study. We estimated causes of death for 37 mortality events with predation serving as the leading known cause of mortality, with 35.1% of mortalities attributed to mesocarnivore predation (e.g., bobcat Lynx rufus, coyote Canis latrans, and gray fox Urocyon cinereoargenteus) and 18.9% to great-horned owl Bubo virginianus predation. One female (2.7%) was hit by a vehicle. Seasonal survival estimates varied from a high during fall (Ŝ = 0.94; 95% CI: 0.86–1.00) to a low during spring (Ŝ = 0.76; 95% CI: 0.68–0.87). Survival of incubating females was 0.82 (95% CI: 0.71–0.93) and survival of nonincubating females was 0.67 (95% CI: 0.52–0.87). Annual survival was 0.55 (95% CI: 0.44–0.67). To ensure sustainable wild turkey populations in longleaf pine savannas, we suggest managers monitor relationships between survival and population productivity

    Testbed Requirements to Enable New Observing Strategies

    Get PDF
    Emerging capabilities to integrate instruments on smallsats, airborne platforms and in situ devices into an intelligent, distributed observing strategy show great promise for measuring Earth science natural phenomena and physical processes that have not previously been characterized. To reduce the threshold for success in deploying such an intelligent, integrated observing strategy, a ground-based testbed system is proposed. Virtually all of the technologies needed for using such a tool have matured to the point of being used, individually. Virtually none of the technologies have been deployed, working together. The technologies to be deployed should be integrated into a working "breadboard" where the components can be debugged and performance and behavior characterized and tuned-up. A system of this complexity should not be expected to work without full integration and experimental characterization. Further, and perhaps more importantly, in order to successfully propose a space-based element to this strategy, teams must convince the relevant science community that the risk is low enough to warrant the investment. The main benefit of the testbed is to retire the risk of integrating these new technologies and increase the Technology Readiness Level (TRL) of each component as well as the System Readiness Level (SRL) of the integrated system

    The written declaration on epilepsy : an important achievement for Europe and beyond

    Get PDF
    On 15th September 2011, the European Written Declaration on Epilepsy was passed by the European Union (EU) Parliament. This was a significant moment for all people who have been fighting over the years for a just recognition of the importance of epilepsy in the European political agenda. The whole process described below included several months of concerted effort by Members of the European Parliament (MEPs) and by Epilepsy Advocacy Europe (EAE), a joint task force of the International League Against Epilepsy (ILAE) and the International Bureau for Epilepsy (IBE). ILAE and IBE member associations in Europe and many individuals also contributed greatly to the success of this initiative.peer-reviewe
    • …
    corecore