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A 13.0 cal ka BP pollen record from Twin Ponds, Vermont, provides new insights into the climate history of the northeastern United States. Modern analogs were used to produce qualitative and quantitative climate reconstructions for Twin Ponds. The Twin Ponds record was compared with nearby Knob Hill Pond to develop a Vermont reconstruction that was compared with reconstructions from two sites at a similar latitude. Postglacial warming at 11.5 cal ka BP followed a cool, wet Younger Dryas and was the largest temperature change of the record. The warmest, driest conditions occurred at ca. 9.0 cal ka BP, followed by an increase in moisture. Latitudinal and elevational shifts in the location of modern analogs from 5.7 to 4.0 cal ka BP were used to infer cooling and increased moisture during the Tsuga canadensis decline. Analysis of the timing of pollen events between the two Vermont sites suggests a more rapid decline in T. canadensis at the more northern Knob Hill Pond and further supports the possibility that colder temperatures contributed to this event. The other northern sites show similar trends until 2.5 cal ka BP, when precipitation in the easternmost site diverges, indicating the establishment of modern climatic gradients.

Safe medication administration is a critical responsibility of registered nurses and is an essential skill developed during nursing education. Student confidence and preparation regarding medication administration are essential aspects of professional skill building. The Confidence and Preparation Survey (CPS) was used previously among homogeneous nursing student samples. The existing dominant discourse, shaped by ideologies and systems, can unfortunately lead to limited perspectives; therefore, the purpose of this study was to evaluate and refine the CPS for feasibility, clarity, and validity among nursing students primarily from groups that have been historically marginalized. A secondary purpose considered the conditions that affect perceived confidence and preparedness. Cognitive interviews were undertaken with baccalaureate nursing students (n = 11) attending an urban college of nursing in the Northeastern region of the United States. Data were analyzed using rapid qualitative techniques and the framework matrix method. The CPS was readily understood and interpreted by this sample. Student perspectives of conditions that influence their understanding and interpretation of the CPS are described under three themes: (1) prior outside of school healthcare experiences influence understanding, (2) school experiences support survey comprehension, and (3) concerns over insufficient training within school. Findings also include a revised CPS instrument ready for further testing.

Tidal marsh loss to anthropogenic environmental impacts and climate change, particularly sea level rise, has and will continue to cause declines in tidal marsh bird populations. Distribution patterns of tidal marsh birds are generally known, yet we lack detailed knowledge of local abundance and regional population sizes, which limits our ability to develop effective conservation strategies that will mitigate the impacts of marsh loss. We designed and implemented a probabilistic sampling framework to establish a regional marsh bird monitoring program, and collected baseline information for breeding tidal marsh birds in the northeastern USA (Maine to Virginia). We sampled 1,780 locations in 2011–2012 to provide regional population estimates for 5 tidal marsh–specialist birds. We estimated that there were 151,000 Clapper Rails (Rallus crepitans; 95% CI = 90,000–212,000), 117,000 Willets (Tringa semipalmata; 95% CI = 88,000–146,000), 5,000 Nelson's Sparrows (Ammodramus nelsoni; 95% CI = 1,000–9,000), 53,000 Saltmarsh Sparrows (A. caudacutus; 95% CI = 37,000–69,000), and 230,000 Seaside Sparrows (A. maritimus; 95% CI = 174,000–286,000) in northeastern tidal marshes. Our baseline assessment can be used to identify local habitat patches important to regional populations for each species and to prioritize conservation actions in targeted areas to maximize tidal marsh bird persistence. The flexibility and probabilistic design of our sampling framework also allow for integration with other monitoring programs (e.g., the U.S. Fish and Wildlife Service Salt Marsh Integrity Program and National Park Service Vital Signs Monitoring Program) so that inferences for these species can be made at multiple spatial scales.

Terrestrial biosphere models are important tools for diagnosing both the current state of the terrestrial carbon cycle and forecasting terrestrial ecosystem responses to global change. While there are a number of ongoing assessments of the short-term predictive capabilities of terrestrial biosphere models using flux-tower measurements, to date there have been relatively few assessments of their ability to predict longer term, decadal-scale biomass dynamics. Here, we present the results of a regional-scale evaluation of the Ecosystem Demography version 2 (ED2)-structured terrestrial biosphere model, evaluating the model's predictions against forest inventory measurements for the northeast USA and Quebec from 1985 to 1995. Simulations were conducted using a default parametrization, which used parameter values from the literature, and a constrained model parametrization, which had been developed by constraining the model's predictions against 2 years of measurements from a single site, Harvard Forest (42.5° N, 72.1° W). The analysis shows that the constrained model parametrization offered marked improvements over the default model formulation, capturing large-scale variation in patterns of biomass dynamics despite marked differences in climate forcing, land-use history and species-composition across the region. These results imply that data-constrained parametrizations of structured biosphere models such as ED2 can be successfully used for regional-scale ecosystem prediction and forecasting. We also assess the model's ability to capture sub-grid scale heterogeneity in the dynamics of biomass growth and mortality of different sizes and types of trees, and then discuss the implications of these analyses for further reducing the remaining biases in the model's predictions.

Temporal changes in net energy balance of animals strongly influence fitness; consequently, natural selection should favor behaviors that increase net energy balance by buffering individuals against negative effects of environmental variation. The relative importance of behavioral responses to climate-induced variation in costs vs. supplies of energy, however, is uncertain, as is the degree to which such responses are mediated by current stores of energy. We evaluated relationships among behavior, nutritional condition (i.e., energy state), and spatiotemporal variation in costs vs. supplies of energy available to a large-bodied endotherm, the North American elk ( Cervus elaphus ), occupying two ecosystems with contrasting climates and energy landscapes: a temperate, montane forest and an arid, high-elevation desert. We hypothesized that during spring through autumn, behavioral responses to the energy landscape would be both context dependent (i.e., would vary as a function of the contrasting environmental conditions experienced by elk in the forest vs. the desert), and state dependent (i.e., would vary as a function of the energy balance of an individual). We tested several predictions derived from that hypothesis by combining output from a biophysical model of the thermal environment with data on forage quality, animal locations, and nutritional condition of individuals. At the population level, elk in the desert selected areas that reduced costs of thermoregulation over those that provided the highest-quality forage. In the forest, however, costs imposed by the thermal environment were less pronounced, and elk selected areas that increased access to high-quality forage over those that reduced costs of thermoregulation. At the individual level, nutritional condition did not influence strength of selection for low-cost areas or high-quality forage among elk in the forest. In the desert, however, strength of selection for low-cost areas (but not forage quality) was state dependent; individuals in the poorest condition at the end of winter showed the strongest selection for areas that reduced costs of thermoregulation during spring and summer, and also expended the least amount of energy on locomotion. Our results highlight the importance of understanding the roles of behavior and nutritional condition in buffering endotherms against direct and indirect effects of climate on fitness.

Our knowledge of climate variability in the densely populated Northeastern United States is limited to instrumental data of the last century. Most regional paleoclimate proxies reflect a mix of climate responses, which makes reconstructing historical climate a challenge. Here we analyze tree-ring chronologies from Atlantic white cedar (Chamaecyparis thyoides) as a potential regional paleotemperature proxy. We evaluate our tree-ring network for spatiotemporal climate signal strength and reconstruction skill across New England. Atlantic white cedar sites in the northern section of the species' range exhibit positive significant annual growth relationships with local and regional temperatures. Chronologies constructed from northern sites yield skillful reconstructions of temperature that reproduce centennial, multidecadal, and interannual variability in the instrumental record, providing a novel paleotemperature record for New England.

We describe a case of morphological anomalies in Amblyomma americanum, a medically important species associated with several human diseases and medical conditions. Based on morphological characters using dichotomous morphological keys, high-resolution light microscopy, and scanning electron microscopy imaging, the tick was identified as Am. americanum nymph exhibiting various morphological anomalies including ectromely associate with asymmetry, olygomely (lack) of the fourth left leg, and schizomely (bifurcation of palpus) on the right side. We believe this is the first report of the presence of several spontaneous anomalies in one Am. americanum specimen. Morphological identity of the specimen was corroborated by DNA sequencing of the mitochondrial 16S region. We discuss recent reports of morphological anomalies in ixodid ticks and emphasize the significance of additional studies of teratology in medically important tick species and its potential implications.

Detrimental impacts of climate change on the international ski tourism industry have been projected in numerous studies. Modeling-based studies project shortened ski seasons and increased snowmaking requirements under warmer temperatures. The present study uses a climate change analogue approach to examine how a wider range of ski area performance indicators were affected by anomalously warm winters in the Northeast region of the USA. The record warm winter of 2001–2002 is representative of projected future average winter climate conditions in the USA Northeast under a high greenhouse gas emission scenario for the 2040–2069 period and was used as one climate change analogue for this analysis. The 1998–1999 ski season was also used as a climate change analogue as it represents the last of 3 consecutive warm winters (1997 to 1999) that are representative of a mid-range emissions scenario projected for the 2040–2069 period. Ski area performance indicators for the 2001–2002 and 1998–1999 analogue years were compared to the climatically normal (based on 1961–1990 means) years of 2000–2001 and 2004–2005. The indicators examined include: ski season length, snowmaking (hours of operation and % energy utilized as a proxy for fuel costs), total skier visits and operating profit (% of total gross fixed assets). The effect of ski season length during the climate change analogue years is compared with modeled effects for the region. The differential vulnerability of small, medium, large and extra-large ski areas was also examined and the greatest economic effects were found among small and extra large ski areas.

ContextProjected increases in human population size are expected to increase forest loss and fragmentation in the next century at the expense of forest-dwelling species.ObjectivesWe estimated landscape carrying capacity (Nk) for Ovenbirds in urban, suburban, exurban, and rural areas for the years 2000 and 2050, and compared changes in Nk with changes in occupancy probability.MethodsMaximum clique analysis, a branch of mathematical graph theory, was used to estimate landscape carrying capacity, the maximum potential number of territories a given landscape is capable of supporting (Nk). We used occupancy probability maps as inputs for calculating Ovenbird Nk in the northeastern USA and a spatially explicit growth model to forecast future development patterns in 2050. We compared occupancy probability with estimates of Nk for urban, suburban, exurban, and rural areas for the years 2000 and 2050.ResultsIn response to human population growth and development, Ovenbird Nk was predicted to decrease 23% in urban landscapes, 28% in suburban landscapes, 43% in exurban landscapes, and 20% in rural landscapes. These decreases far exceeded decreases in mean occupancy probabilities that ranged between 2 and 5% across the same development categories. Thus, small decreases in occupancy probability between 2000 and 2050 translated to much larger decreases in Nk.ConclusionsFor the first time, our study compares occupancy probability with a species population metric, Nk, to assess the impact of future development. Maximum clique analysis is a tool that can be used to estimate Nk and inform landscape management and communication with stakeholders.

Long‐term, ecosystem‐specific fire regime information improves natural community restoration and management by providing a basis for scientifically reasoned fire management prescriptions. Historical fire regimes can be reconstructed to sub‐annual resolution using fire‐scarred trees, and while such reconstructions have become increasingly prevalent across the eastern USA, little information regarding how they vary at landscape scale is available. Most studies report fire regime characteristics (i.e., frequency, seasonality) at site‐composite levels, commonly at ≤1 km2 spatial resolution. In this study, we analyzed the historical spatial variation of fire regime characteristics over the past four centuries (1620 CE to present) in a red pine/oak landscape (30.75 km2) in north‐central Pennsylvania, USA. Fire event data were reconstructed based on fire scars and locations of 192 living and dead red pines. The spatial and temporal distributions of fire scars revealed a historical fire regime dominated by frequent, dormant season fires most often detected at relatively small spatial extents and by relatively few trees. There was, however, evidence of less frequent, relatively large fires that scarred high percentages of trees. These fire regime characteristics likely resulted in a spatially and temporally transient patchwork of varying vegetation age and structures resulting in a heterogeneous landscape. At the landscape scale, fire frequency changed with human cultures, while fire spatial extent and scarring patterns appeared to be modulated by drought conditions. Results from this study show historical precedence for landscape‐scale burning across a broad range of drought conditions and spatial extents, which should be considered when designing fire‐management and ecosystem restoration objectives.