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By 1985, approximately 400,000 ha of the keystone species Shinnery oak's (Quercus havardii) historic distribution had been eliminated for agricultural purposes across the southwestern United States. These trends indicate a need for targeted conservation and restoration efforts, especially considering the increased attention received for its role in providing habitat for endangered fauna. Setting spatially explicit conservation targets can be challenging for species with limited distributions, as the change in climate conditions over time may disconnect the relationship between environmental suitability and static, topo‐edaphic factors. Our objective was to identify areas for Shinnery oak restoration and conservation and explore the role climate plays in determining these areas while considering topo‐edaphic relationships. We constructed ecological niche models to estimate Shinnery oak's distribution under current climate conditions and temporally transferred our model using an ensemble‐mean of general circulation models to identify areas predicted to retain environmental suitability for Shinnery oak through 2100. The current distribution model was best informed by one climate and two topo‐edaphic variables. We created a second distribution model excluding topo‐edaphic variables to estimate future plant–climate relationships. Incorporating insights from models informed by both static (e.g. soil) and dynamic (e.g. climate) variables, we identified areas for conservation characterized by persistent climate suitability and high soil type suitability. Lastly, we incorporated data on land use and ownership to explore socio‐ecological influences on management decisions. By identifying areas of agreement between our modeled distributions and considering social context, we prioritized conservation areas where environmental suitability persists under changing conditions to facilitate restoration success. [ABSTRACT FROM AUTHOR]

Since recognizing the importance of bioavailability for understanding the toxicity of chemicals in sediments, mechanistic modeling has advanced over the last 40 years by building better tools for estimating exposure and making predictions of probable adverse effects. Our review provides an up‐to‐date survey of the status of mechanistic modeling in contaminated sediment toxicity assessments. Relative to exposure, advances have been most substantial for non‐ionic organic contaminants (NOCs) and divalent cationic metals, with several equilibrium partitioning‐based (Eq‐P) models having been developed. This has included the use of Abraham equations to estimate partition coefficients for environmental media. As a result of the complexity of their partitioning behavior, progress has been less substantial for ionic/polar organic contaminants. When the EqP‐based estimates of exposure and bioavailability are combined with water‐only effects measurements, predictions of sediment toxicity can be successfully made for NOCs and selected metals. Both species sensitivity distributions and toxicokinetic and toxicodynamic models are increasingly being applied to better predict contaminated sediment toxicity. Furthermore, for some classes of contaminants, such as polycyclic aromatic hydrocarbons, adverse effects can be modeled as mixtures, making the models useful in real‐world applications, where contaminants seldomly occur individually. Despite the impressive advances in the development and application of mechanistic models to predict sediment toxicity, several critical research needs remain to be addressed. These needs and others represent the next frontier in the continuing development and application of mechanistic models for informing environmental scientists, managers, and decisions makers of the risks associated with contaminated sediments. Environ Toxicol Chem 2024;43:1778–1794. © 2023 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Technical complexity associated with biodegradation testing, particularly for substances of unknown or variable composition, complex reaction products, or biological materials (UVCB), necessitates the advancement of non‐testing methods such as quantitative structure–property relationships (QSPRs). Models for describing the biodegradation of petroleum hydrocarbons (HCs) have been previously developed. A critical limitation of available models is their inability to capture the variability in biodegradation rates associated with variable test systems and environmental conditions. Recently, the Hydrocarbon Biodegradation System Integrated Model (HC‐BioSIM) was developed to characterize the biodegradation of HCs in aquatic systems with the inclusion of key test system variables. The present study further expands the HC‐BioSIM methodology to soil and sediment systems using a database of 2195 half‐life (i.e., degradation time [DT]50) entries for HCs in soil and sediment. Relevance and reliability criteria were defined based on similarity to standard testing guidelines for biodegradation testing and applied to all entries in the database. The HC‐BioSIM soil and sediment models significantly outperformed the existing biodegradation HC half‐life (BioHCWin) and virtual evaluation of chemical properties and toxicities (VEGA) quantitative Mario Negri Institute for Pharmacological Research (IRFMN) models in soil and sediment. Average errors in predicted DT50s were reduced by up to 6.3‐ and 8.7‐fold for soil and sediment, respectively. No significant bias as a function of HC class, carbon number, or test system parameters was observed. Model diagnostics demonstrated low variability in performance and high consistency of parameter usage/importance and rule structure, supporting the generalizability and stability of the models for application to external data sets. The HC‐BioSIM provides improved accuracy of Persistence categorization, with correct classification rates of 83.9%, and 90.6% for soil and sediment, respectively, demonstrating a significant improvement over the existing BioHCWin (70.7% and 58.6%) and VEGA (59.5% and 18.5%) models. Environ Toxicol Chem 2024;43:1352–1363. © 2024 Concawe. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing (HF) is commonly used to enhance onshore recovery of oil and gas during production. This process involves the use of a variety of chemicals to support the physical extraction of oil and gas, maintain appropriate conditions downhole (e.g., redox conditions, pH), and limit microbial growth. The diversity of chemicals used in HF presents a significant challenge for risk assessment. The objective of the present study is to establish a transparent, reproducible procedure for estimating 5th percentile acute aquatic hazard concentrations (e.g., acute hazard concentration 5th percentiles [HC5s]) for these substances and validating against existing toxicity data. A simplified, grouped target site model (gTSM) was developed using a database (n = 1696) of diverse compounds with known mode of action (MoA) information. Statistical significance testing was employed to reduce model complexity by combining 11 discrete MoAs into three general hazard groups. The new model was trained and validated using an 80:20 allocation of the experimental database. The gTSM predicts toxicity using a combination of target site water partition coefficients and hazard group‐based critical target site concentrations. Model performance was comparable to the original TSM using 40% fewer parameters. Model predictions were judged to be sufficiently reliable and the gTSM was further used to prioritize a subset of reported Permian Basin HF substances for risk evaluation. The gTSM was applied to predict hazard groups, species acute toxicity, and acute HC5s for 186 organic compounds (neutral and ionic). Toxicity predictions and acute HC5 estimates were validated against measured acute toxicity data compiled for HF substances. This case study supports the gTSM as an efficient, cost‐effective computational tool for rapid aquatic hazard assessment of diverse organic chemicals. Environ Toxicol Chem 2024;43:1161–1172. © 2024 ExxonMobil Petroleum and Chemical BV. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Wetland ecosystems are vital for maintaining global biodiversity, as they provide important stopover sites for many species of migrating wetland-associated birds. However, because weather determines their hydrologic cycles, wetlands are highly vulnerable to effects of climate change. Although changes in temperature and precipitation resulting from climate change are expected to reduce inundation of wetlands, few efforts have been made to quantify how these changes will influence the availability of stopover sites for migratory wetland birds. Additionally, few studies have evaluated how climate change will influence interannual variability or the frequency of extremes in wetland availability. For spring and fall bird migration in seven ecoregions in the south-central Great Plains of North America, we developed predictive models associating abundance of inundated wetlands with a suite of weather and land cover variables. We then used these models to generate predictions of wetland inundation at the end of the century (2069-2099) under future climate change scenarios. Climate models predicted the average number of inundated wetlands will likely decline during both spring and fall migration periods, with declines being greatest in the eastern ecoregions of the southern Great Plains. However, the magnitude of predicted declines varied considerably across climate models and ecoregions, with uncertainty among climate models being greatest in the High Plains ecoregion. Most ecoregions also were predicted to experience more-frequent extremely dry years (i.e., years with extremely low wetland abundances), but the projected change in interannual variability of wetland inundation was relatively small and varied across ecoregions and seasons. Because the south-central Great Plains represents an important link along the migratory routes of many wetland-dependent avian species, future declines in wetland inundation and more frequent periods of only a few wetlands being inundated will result in an uncertain future for migratory birds as they experience reduced availability of wetland stopover habitat across their migration pathways. [ABSTRACT FROM AUTHOR]

Regulation of per‐ and polyfluorinated substances (PFAS) in surface water is a work‐in‐progress with relatively few criteria promulgated in the United States and internationally. Surface water quality criteria (SWQC) or screening values derived for perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) by Australia, Canada, the European Union (EU), and four US states (Florida, Michigan, Minnesota, and Wisconsin), and the San Francisco Bay Regional Water Quality Control Board (SFB RWQCB; California) were compared. Across these eight jurisdictions, promulgated numeric criteria for the same compound and receptor span over five orders of magnitude as a result of different approaches and data interpretations. Human health criteria for PFOS range from 0.0047 to 600 ng/L depending on route of exposure (e.g., fish consumption or drinking water) and are lower than most ecological criteria for protection of aquatic and wildlife receptors. Data gaps and uncertainty in chronic toxicity and bioaccumulation of PFOS and PFOA, as well as the use of conservative assumptions regarding intake and exposure, have resulted in some criteria falling at or below ambient background concentrations and current analytical detection limits (around 1 ng/L for commercial laboratories). Some jurisdictions (e.g., Australia, Canada) have deemed uncertainty in quantifying water‐fish bioaccumulation too great and set fish tissue action levels in lieu of water criteria. Current dynamics associated with the emerging and evolving science of PFAS toxicity, exposure, and environmental fate (i.e., data gaps and uncertainty), as well as the continuous release of scientific updates, pose a challenge to setting regulatory limits. Integr Environ Assess Manag 2024;20:36–58. © 2023 AECOM Technical Services, Inc and The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points: Surface water quality criteria (SWQC) for per‐ and polyfluorinated substances (PFAS) are currently limited.Across the eight jurisdictions reviewed, numeric SWQC for the same compound and receptor span over five orders of magnitude as a result of different mechanistic and empirical approaches and data interpretations.Some SWQC are below ambient background levels and analytical detection limits.Data gaps and uncertainty in PFAS toxicity, exposure, and environmental fate, as well as rapidly evolving science, pose a challenge to setting regulatory limits. [ABSTRACT FROM AUTHOR]

Key Takeaways: As critical infrastructure, water systems must be designed to withstand seismic hazards where earthquakes are expected. While several planning tools and design solutions exist for seismic hazards, they are not standardized for the water community. Designing buried infrastructure to withstand differential ground movement and severe shaking comes with several challenges for water systems. [ABSTRACT FROM AUTHOR]

Arthropod consumption provides amino acids to invertebrates and vertebrates alike, but not all amino acids in arthropods may be digestible as some are bound in the exoskeleton. Consumers may not be able to digest exoskeleton in significant amounts or avoid it entirely (e.g., extraoral digestion). Hence, measures that do not separate digestible amino acids from those in exoskeleton may not accurately represent the amino acids available to consumers. Additionally, arthropods are taxonomically diverse, and it remains unclear if taxonomic differences also reflect differences in amino acid availability. Thus, we tested: (1) if there were consistent differences in the content and balance of amino acids between the digestible tissue and exoskeleton of arthropods and (2) if arthropod Orders differ in amino acid content and balance. We measured the amino acid content (mg/100 mg dry mass) and balance (mg/100 mg protein) of whole bodies and exoskeleton of a variety of arthropods using acid hydrolysis. Overall, there was higher amino acid content in digestible tissue. There were also significant differences in the amino acid balance of proteins in digestible tissue and exoskeleton. Amino acid content and balance also varied among Orders; digestible tissues of Hemiptera contained more of some essential amino acids than other Orders. These results demonstrate that arthropod taxa vary in amino acid content, which could have implications for prey choice by insectivores. In addition, exoskeleton and digestible tissue content differ in arthropods, which means that whole body amino acid content of an arthropod is not necessarily a predictor of amino acid intake of a predator that feeds on that arthropod. [ABSTRACT FROM AUTHOR]

Hydrocarbon solvents are a diverse group of petrochemical substances that are identified as unknown or variable composition, complex reaction products, or biological materials (UVCBs) and may contain tens of thousands of individual chemical constituents. As such, it is generally not possible to analytically resolve every chemical constituent in a hydrocarbon solvent. This, along with the low water solubility and/or high vapor pressure of constituents, precludes the use of many standardized tests designed to determine biodegradation in the environment (e.g., Organization for Economic Co‐operation and Development [OECD] 309). A weight of evidence approach may be needed to reduce uncertainty to an acceptable level such that a determination on the biodegradation of the substance can be drawn. Based on the OECD 2019 weight of evidence guidance, we present a framework using various lines of evidence that can be used to evaluate the biodegradation of a UVCB solvent in a weight of evidence approach. The lines of evidence include whole substance testing, data on representative constituents, quantitative structure activity relationship (QSAR) models, and biological plausibility. Using these lines of evidence, "Hydrocarbon, C11–C14, normal alkane, isoalkane, cyclic, <2% aromatics" (EC# 926‐141‐6) was evaluated in a case study. Data from three whole substance tests, 43 constituents (representing 152 data points), three QSAR models and evidence of microbial degradation pathways were evaluated. Based on the available data, it is concluded that the solvent for the case study is not expected to persist in the environment. This framework sets out a real‐world example of how the weight of evidence can be used to evaluate hydrocarbon solvents. While focused on persistence, similar approaches can be used to evaluate other endpoints such as bioaccumulation and toxicity. Integr Environ Assess Manag 2023;19:1120–1130. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points: Hydrocarbon solvents are a diverse group of UVCB substances for which environmental fate and hazard assessments can be challenging.A case study using the weight of evidence was applied to a hydrocarbon solvent in an attempt to conclude on degradation potential.Based on the weight of evidence, it could be concluded that the hydrocarbon solvent from the case study would not be predicted to persist in the environment. [ABSTRACT FROM AUTHOR]

Invasive species are suspected to be major contributors to biodiversity declines worldwide. Counterintuitively, however, invasive species effects are likely scale dependent and are hypothesized to be positively related to biodiversity at large spatial scales. Past studies investigating the effect of invasion on biodiversity have been mostly conducted at small scales (<100 m2) that cannot represent large dynamic landscapes by design. Therefore, replicated experimental evidence supporting a negative effect of invasive plants on biodiversity is lacking across many landscape types, including large grasslands.We collected data across eight large (333–809 ha) grassland landscapes managed with pyric herbivory—that is the recoupling of fire and grazing—to test how an invasive legume Lespedeza cuneata affected plant and bird communities at spatial grains ranging from 0.1 m2 to >3,000,000 m2.Lespedeza cuneata invasion effects on grassland plant diversity and composition changed with scale, being negative at small spatial grains (0.1 m2) and neutral or positive at large spatial grains (>3,000,000 m2).Lespedeza cuneata abundance did not significantly affect bird diversity at any spatial grain measured.Lespedeza cuneata may negatively affect biodiversity if abundances are greater than those observed in this study. However, previous research suggests that Lespedeza cuneata may not be capable of exceeding 20% canopy cover across large landscapes (>400 ha). Control and eradication strategies can be costly and are fraught with risk. If data do not clearly support a negative Lespedeza cuneata abundance–biodiversity relationship, and if invasion is spatially limited across large landscapes, ongoing control and eradication efforts may be unwarranted and ineffective.Synthesis and applications: Invasive species effects gleaned from small‐scale studies may not reliably predict their effects at larger scales. Although we recognize the importance of small‐scale studies in potentially isolating individual mechanisms, management strategies based solely on results from small‐scale studies of invasion are unlikely to increase or conserve biodiversity across large landscapes. Rather, processes that generate landscape heterogeneity—like pyric herbivory—are probably more important for promoting biodiversity across all scales. Scale is a central problem in ecology, and defining scale in management objectives is essential for effective biodiversity conservation. [ABSTRACT FROM AUTHOR]

Recent declines in eastern wild turkeys (Meleagris gallopavo silvestris) have prompted increased interest in management and research of this important game species. However, the mechanisms underlying these declines are unclear, leaving uncertainty in how best to manage this species. Foundational to effective management of wildlife species is understanding the biotic and abiotic factors that influence demographic parameters and the contribution of vital rates to population growth. Our objectives for this study were to (1) conduct a literature review to collect all published vital rates for eastern wild turkey over the last 50 years, (2) perform a scoping review of the biotic and abiotic factors that have been studied relative to wild turkey vital rates and highlight areas that require additional research, and (3) use the published vital rates to populate a life‐stage simulation analysis (LSA) and identify the vital rates that make the greatest contribution to population growth. Based on published vital rates for eastern wild turkey, we estimated a mean asymptotic population growth rate (λ) of 0.91 (95% CI = 0.71, 1.12). Vital rates associated with after‐second‐year (ASY) females were most influential in determining population growth. Survival of ASY females had the greatest elasticity (0.53), while reproduction of ASY females had lower elasticity (0.21), but high process variance, causing it to explain a greater proportion of variance in λ. Our scoping review found that most research has focused on the effects of habitat characteristics at nest sites and the direct effects of harvest on adult survival, while research on topics such as disease, weather, predators, or anthropogenic activity on vital rates has received less attention. We recommend that future research take a more mechanistic approach to understanding variation in wild turkey vital rates as this will assist managers in determining the most appropriate management approach. [ABSTRACT FROM AUTHOR]

Animal movement patterns are affected by complex interactions between biotic and abiotic landscape conditions, and these patterns are being altered by weather variability associated with a changing climate. Some animals, like the American plains bison (Bison bison L.; hereafter, plains bison), are considered keystone species, thus their response to weather variability may alter ecosystem structure and biodiversity patterns. Many movement studies of plains bison and other ungulates have focused on point‐pattern analyses (e.g., resource‐selection) that have provided information about where these animals move, but information about when or why these animals move is limited. For example, information surrounding the influence of weather on plains bison movement in response to weather is limited but has important implications for their conservation in a changing climate. To explore how movement distance is affected by weather patterns and drought, we utilized 12‐min GPS data from two of the largest plains bison herds in North America to model their response to weather and drought parameters using generalized additive mixed models. Distance moved was best predicted by air temperature, wind speed, and rainfall. However, air temperature best explained the variation in distance moved compared to any other single parameter we measured, predicting a 48% decrease in movement rates above 28°C. Moreover, severe drought (as indicated by 25‐cm depth soil moisture) better predicted movement distance than moderate drought. The strong influence of weather and drought on plains bison movements observed in our study suggest that shifting climate and weather will likely affect plains bison movement patterns, further complicating conservation efforts for this wide‐ranging keystone species. Moreover, changes in plains bison movement patterns may have cascading effects for grassland ecosystem structure, function, and biodiversity. Plains bison and grassland conservation efforts need to be proactive and adaptive when considering the implications of a changing climate on bison movement patterns. [ABSTRACT FROM AUTHOR]

Quantitative structure–property relationship (QSPR) models for predicting primary biodegradation of petroleum hydrocarbons have been previously developed. These models use experimental data generated under widely varied conditions, the effects of which are not captured adequately within model formalisms. As a result, they exhibit variable predictive performance and are unable to incorporate the role of study design and test conditions on the assessment of environmental persistence. To address these limitations, a novel machine‐learning System‐Integrated Model (HC‐BioSIM) is presented, which integrates chemical structure and test system variability, leading to improved prediction of primary disappearance time (DT50) values for petroleum hydrocarbons in fresh and marine water. An expanded, highly curated database of 728 experimental DT50 values (181 unique hydrocarbon structures compiled from 13 primary sources) was used to develop and validate a supervised model tree machine‐learning model. Using relatively few parameters (6 system and 25 structural parameters), the model demonstrated significant improvement in predictive performance (root mean square error = 0.26, R2 = 0.67) over existing QSPR models. The model also demonstrated improved accuracy of persistence (P) categorization (i.e., "Not P/P/vP"), with an accuracy of 96.8%, and false‐positive and ‐negative categorization rates of 0.4% and 2.7%, respectively. This significant improvement in DT50 prediction, and subsequent persistence categorization, validates the need for models that integrate experimental design and environmental system parameters into biodegradation and persistence assessment. Environ Toxicol Chem 2022;41:1359–1369. © 2022 ExxonMobil Biomedical Sciences, Inc. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

The challenge of conserving viable habitat while simultaneously predicting how land cover may geographically shift with future climate change has put pressure on ecologists and policy‐makers to develop near‐term (several years to a decade) ecological and geospatial predictions. This is particularly relevant for endangered species as ranges adjust to track a changing climate. The whooping crane is vulnerable to these changes, as the overwintering habitat of a small population is susceptible to climate impacts. This study mapped the historical spatial transformation of crane habitat in and around the Aransas National Wildlife Refuge. A time series of ecological niche models was developed to determine the biotic and abiotic factors correlated with crane presence and track how importance has changed over time. The results from the multitemporal models were used to predict areas along the US Gulf Coast where additional unoccupied habitat may be located for crane population expansion and model how the areas may degrade or change as sea levels rise through future climate change scenarios. Findings indicate that the percentage of emergent herbaceous wetland and water are the most important variables influencing crane presence. Sea level rise analysis indicates that potential habitat throughout the Texas–Louisiana Gulf Coast will be impacted considerably by climate change. The lack of large, continuous blocks of usable land cover could limit population expansion and future recovery efforts. However, the findings can help facilitate winter range expansion to accommodate the growing population by identifying additional areas to protect that could be used by the current wild population or experimental populations. [ABSTRACT FROM AUTHOR]

Movement and selection are inherently linked behaviors that form the foundation of a species' space‐use patterns. Anthropogenic development in natural ecosystems can result in a variety of behavioral responses that can involve changes in either movement (speed or direction of travel) or selection (resources used), which in turn may cause population‐level consequences including loss of landscape connectivity. Understanding how a species alters these different behaviors in response to human activity is essential for effective conservation. In this study, we investigated the effects of anthropogenic development such as roads, power lines and oil wells on the greater prairie‐chicken (Tympanuchus cupido) movement and selection behaviors in the post‐nesting and non‐breeding season. Our first objective was to assess using integrated step selection analysis (iSSA) if greater prairie‐chickens altered their movement behaviors or their selection patterns when encountering oil wells, power lines, or roads. Our second objective was to determine whether prairie‐chickens avoided crossing linear features such as roads or power lines by comparing the number of crossing events in greater prairie‐chicken movement tracks to the number of movements that crossed these features in simulated movement tracks. Based on the iSSA analysis, we found that greater prairie‐chickens avoided oil wells, power lines, and roads in both seasons, and altered their rate of movement when near anthropogenic structures. However, changes in speed varied by season, with prairie‐chickens increasing their movement rates in the post‐nesting season when near to development and decreasing movement rates in the non‐breeding season. Furthermore, prairie‐chickens crossed roads and power lines at much lower rates than expected. These changes in behavior can result in habitat loss for greater prairie‐chickens, as well as the potential loss of landscape connectivity. By considering both movement and selection, we were able to develop an ecological understanding of how increasing human activity may influence the space use of this species of conservation concern. Furthermore, this research provides insight into the decision‐making processes by animals when they encounter anthropogenic development. [ABSTRACT FROM AUTHOR]

Global climate change is causing increased climate extremes threatening biodiversity and altering ecosystems. Climate is comprised of many variables including air temperature, barometric pressure, solar radiation, wind, relative humidity, and precipitation that interact with each other. As movement connects various aspects of an animal's life, understanding how climate influences movement at a fine‐temporal scale will be critical to the long‐term conservation of species impacted by climate change. The sedentary nature of non‐migratory species could increase some species risk of extirpation caused by climate change. We used Northern Bobwhite (Colinus virginianus; hereafter bobwhite) as a model to better understand the relationship between climate and the movement ecology of a non‐migratory species at a fine‐temporal scale. We collected movement data on bobwhite from across western Oklahoma during 2019–2020 and paired these data with meteorological data. We analyzed movement in three different ways (probability of movement, hourly distance moved, and sinuosity) using two calculated movement metrics: hourly movement (displacement between two consecutive fixes an hour apart) and sinuosity (a form of tortuosity that determines the amount of curvature of a random search path). We used generalized linear‐mixed models to analyze probability of movement and hourly distance moved, and used linear‐mixed models to analyze sinuosity. The interaction between air temperature and solar radiation affected probability of movement and hourly distance moved. Bobwhite movement increased as air temperature increased beyond 10°C during low solar radiation. During medium and high solar radiation, bobwhite moved farther as air temperature increased until 25–30°C when hourly distance moved plateaued. Bobwhite sinuosity increased as solar radiation increased. Our results show that specific climate variables alter the fine‐scale movement of a non‐migratory species. Understanding the link between climate and movement is important to determining how climate change may impact a species' space use and fitness now and in the future. [ABSTRACT FROM AUTHOR]

Insectivores gain macronutrients and elements from consuming arthropod prey, but must also deal with indigestible components (i.e., exoskeleton) of prey. For example, avian chicks (e.g., northern bobwhites; Colinus virginianus) have limited gut space, and ingesting prey with relatively higher proportions of indigestible components may impact assimilation efficiency, growth, and survival. The ability of insectivores to choose higher quality prey would depend on prey taxa varying consistently in nutritional content. We tested whether there were consistent differences among taxonomic orders of arthropod prey in their macronutrient (protein and lipid), elemental (C and N), and exoskeleton content. We used northern bobwhite chicks as our focal insectivore and focused on their potential prey as a case study. We also tested the influence of indigestible exoskeleton on the measurement of macronutrient content and the ability of elemental content to predict macronutrients. We found large and consistent variation in macronutrient and elemental content between arthropod orders. Some orders had consistently high protein content and low exoskeleton content (i.e., Araneae) and are likely higher quality prey for insectivores. Abundant orders common in the diets of insectivores, like Hymenoptera and Coleoptera, had high exoskeleton content and low protein content. We also found support for the ability of elements to predict macronutrients and found that metabolizable (i.e., exoskeleton removed) elemental content better predicted macronutrient content. A better understanding of arthropod nutrient content is critical for elucidating the role of spatial and temporal variation in prey communities in shaping the growth and survival of insectivores. [ABSTRACT FROM AUTHOR]

Quantifying resource selection (an organism's disproportionate use of available resources) is essential to infer habitat requirements of a species, develop management recommendations, predict species responses to changing conditions, and improve our understanding of the processes that underlie ecological patterns. Because study sites, even within the same region, can differ in both the amount and the arrangement of cover types, our objective was to determine whether proximal sites can yield markedly different resource selection results for a generalist bird, northern bobwhite (Colinus virginianus). We used 5 years of telemetry locations and newly developed land cover data at two, geographically distinct but relatively close sites in the south‐central semi‐arid prairies of North America. We fit a series of generalized linear mixed models and used an information‐theoretic model comparison approach to identify and compare resource selection patterns at each site. We determined that the importance of different cover types to northern bobwhite is site‐dependent on relatively similar and nearby sites. Specifically, whether bobwhite selected for shrub cover and whether they strongly avoided trees, depended on the study site in focus. Additionally, the spatial scale of selection was nearly an order of magnitude different between the cover types. Our study demonstrates that—even for one of the most intensively studied species in the world—we may oversimplify resource selection by using a single study site approach. Managing the trade‐offs between practical, generalized conclusions and precise but complex conclusions is one of the central challenges in applied ecology. However, we caution against setting recommendations for broad extents based on information gathered at small extents, even for a generalist species at adjacent sites. Before extrapolating information to areas beyond the data collected, managers should account for local differences in the availability, arrangement, and scaling of resources. [ABSTRACT FROM AUTHOR]

Arthropods are abundant and diverse animals in many terrestrial food webs. In western Oklahoma, some shrublands are interspersed with discrete, dense thickets of tall, woody vegetation, known as mottes. Some of these shrublands are managed with prescribed burning. The goal of this study was to examine whether prescribed burning interacted with habitat type (i.e., shrubland versus mottes) to affect ground‐dwelling arthropod communities. Arthropods were collected in pitfall traps at four sampling locations in relation to mottes; in the center of mottes, and three plot location in shrublands; 1 m, 15 m, and 50 m away from the edge of the motte. There were three treatment levels for burning: one year postburn (burned in dormant months of 2017), two years postburn (burned in dormant months of 2016), and unburned (burned in dormant season of 2014 and prior). There were no significant interactions between prescribed burning and habitat type. Mottes had a different community of arthropods compared with the surrounding shrubland. Mottes also had lower overall abundance, but a higher diversity of arthropods. In terms of fires, arthropod communities one year after burning were different from those two or more years after burning. There was no effect of burning on overall arthropod abundance, but plots that were one year since burning had significantly lower diversity compared with plots that were two or more years postburn. The results of this study suggest that both fire and mottes can independently facilitate heterogeneity in arthropod communities, but they do not appear to interact with one another. [ABSTRACT FROM AUTHOR]

The American plains bison (Bison bison) is an iconic herbivore on North American grasslands, yet many questions surrounding their basic biology remain unanswered. We analyzed fine‐resolution movement data (12 minute) from two of the largest remaining prairie tracts in the Great Plains of North America to address whether bison movement and distance travelled are affected by seasonal or diurnal rhythms. We fit binomial movement and movement distance data to generalized linear mixed models to test whether site, season, or time of day affected movement. Our top models included season‐site and season‐time of day interactions as fixed effects. Overall, bison were more likely to move during the day than at night regardless of season or site. There was considerable overlap between our sites across most seasons, with the strongest divergence occurring in autumn for movement probability and distance. During the summer, daytime bison movement declined in favor of nighttime movement, potentially in response to high temperatures. Day and nighttime movement distance and probability both were lowest in the winter. That site alone was not a significant predictor of bison movement or movement distance may suggest that their response to seasonal and diurnal rhythms is biologically innate. Therefore, we conclude that season and time of day should be considered in future bison movement analyses. Here, we present the first replicated analysis of fine‐resolution, seasonal, and diurnal bison movements across two large complex landscapes using a long‐term dataset. As ungulate behavior changes in response to the Anthropocene, filling the knowledge gaps in their basic biology is critical to their continued conservation. [ABSTRACT FROM AUTHOR]

The influence of weather on wildlife populations has been documented for many species; however, much of the current literature has focused on the effects of weather within a season and consists of short‐term studies. The use of long‐term datasets that cover a variety of environmental conditions will be essential for assessing possible carry‐over effects of weather experienced in one season on behavior and fitness in subsequent seasons. In this study, we evaluated the effects of weather variables measured over multiple temporal scales on the reproductive performance and behavior of greater prairie‐chickens (Tympanuchus cupido) in Osage County, Oklahoma, USA, from 2011–2019. Considering weather over a range of temporal extents allowed us to determine the relative importance of short‐term weather events, such as daily temperature and precipitation, versus more chronic shifts in weather such as persistent drought on the reproductive performance of greater prairie‐chickens. We used an information‐theoretic model building approach to develop models describing the effects of daily weather variables and drought conditions on daily nest survival, nest incubation start dates, and clutch size. Daily nest survival was primarily influenced by conditions experienced during incubation with daily nest success declining in years with wetter than average springs and during extreme precipitation events. Daily nest survival also declined under higher maximum daily temperatures, especially in years with below‐average rainfall. Greater prairie‐chickens began nesting earlier and had smaller clutch sizes for initial nests and renests in years with warmer temperatures prior to the nesting season. Additionally, incubation of nests started later in drought years, indicating carry‐over effects in greater prairie‐chicken reproductive behaviors. Our work shows that if the weather in the Great Plains becomes more variable, with increasing frequency of drought and extreme precipitation events, wildlife species that inhabit these grassland landscapes will likely experience changes in reproduction, potentially influencing future populations. © 2020 The Wildlife Society. Female greater prairie‐chickens experience reduced reproductive output due to extreme weather conditions in the Southern Great Plains, USA. In particular, daily nest survival declined in years with above average rainfall during the nesting season and on days that experienced extreme rainfall events. Further, warmer spring temperatures resulted in earlier nest initiation dates, smaller clutch sizes, and reduced daily nest survival. [ABSTRACT FROM AUTHOR]

Heterogeneity has a critical influence on biodiversity and ecosystem processes. While the influence of heterogeneity on species diversity and abundance is well documented, how heterogeneity influences the distribution and arrangement of necessary resources across a landscape is still unclear. Heterogeneity in vegetation structure and composition is often cited as an important factor in the nearground thermal environment; however, because of a paucity of comparative studies across landscapes that differ in their degree of vegetation heterogeneity, researchers lack knowledge of the underlying mechanisms that influence variation in the thermal environment. Particularly, we do not have a clear understanding of the relative contribution of structural and compositional vegetation heterogeneity to thermal patterns. Therefore, we assessed the thermal environment in nine grassland landscapes that differed in their degree of structural and compositional heterogeneity. At the landscape level, we used a variance partitioning approach with linear mixed models to measure the link between four metrics of vegetation heterogeneity and temperature variability. At the microsite level, we used piecewise structural equation models to assess the fine-scale drivers of temperature in these landscapes and develop a causal model describing the relationship between vegetation variables and temperature. We found that temperature variance at the landscape scale was strongly related to the diversity of plant functional groups, heterogeneity in plant species composition, and variation in vegetation height. At finer scales, species richness, vegetation height, and overhead obstruction were the best predictors of temperature once weather was accounted for. Vegetation composition variables indirectly influenced fine-scale temperature variation through their effects on vegetation structure. These results suggest that scale has a strong influence on the observed relationship between temperature variance and different metrics of vegetation heterogeneity. Our results provide support for the role of landscape heterogeneity in shaping the thermal landscape and offer insights into the possible impacts of habitat homogenization on the thermal environment. [ABSTRACT FROM AUTHOR]

With the advent of global regulations for safer detergent and an emphasis on a shift toward more environmentally friendly formulations, the environmental profile of surfactant chemistries have moved to the forefront of product formulation and design. The two cornerstones of surfactant environmental profiles are the ability to biodegrade in the natural environment and the ecological hazard profile. The objectives of this article are to describe biodegradation and aquatic toxicity data for a series of branched oxo‐alcohol ethoxylate (AEO) surfactants; to apply the target lipid model (TLM) for deriving model‐based threshold hazard concentrations (HC5) of AEO; and, finally, to accurately determine aquatic classifications for AEO surfactants for use in regulatory classification frameworks. Biodegradation results indicate a high level of biodegradability of branched AEO, with C8–C13‐rich oxo‐alcohols with 1–20 mol of ethoxylate meeting the readily biodegradable criteria. Results from acute and chronic toxicity tests indicated comparable or lesser aquatic toxicity versus linear AEO structures previously reported in the literature. The TLM model, applied a priori, resulted in good agreement with acute toxicity data (RMSE = 0.49) and is comparable to the root mean square errors (RMSE) previously determined for other narcotic chemicals (RMSE = 0.46–0.57). Model errors for invertebrates and fish were smaller than those for algae, with the TLM systematically overpredicting acute and chronic classification of two of seven branched AEO. Furthermore, TLM‐predicted HC5 values were determined to be sufficiently conservative, with 100% of observed chronic data (N = 79) falling above the HC5 threshold values, providing a useful tool for the risk assessment of AEO. [ABSTRACT FROM AUTHOR]

Life‐history theory suggests species that typically have a large number of offspring and high adult mortality may make decisions that benefit offspring survival in exchange for increased adult risks. Such behavioral adaptations are essential to understanding how demographic performance is linked to habitat selection during this important life‐history stage. Though studies have illustrated negative fitness consequences to attendant adults or potential fitness benefits to associated offspring because of adaptive habitat selection during brood rearing, equivocal relationships could arise if both aspects of this reproductive trade‐off are not assessed simultaneously. To better understand how adaptive habitat selection during brood rearing influences demographics, we studied the brood survival, attendant parental survival, and space use of two sympatric ground‐nesting bird species, the northern bobwhite (hereafter: "bobwhite"; Colinus virgininanus) and scaled quail (Callipepla squamata). During the 2013–2014 breeding seasons, we estimated habitat suitability across two grains (2 m and 30 m) for both species and determined how adult space use of these areas influenced individual chick survival and parental risk. We found the proportion of a brood's home range containing highly suitable areas significantly increased bobwhite chick survival (β = 0.02, SE = 0.006). Additionally, adult weekly survival for bobwhite was greater for individuals not actively brooding offspring (0.9716, SE = 0.0054) as compared to brooding adults (0.8928, SE = 0.0006). Conversely, brood habitat suitability did not influence scaled quail chick survival during our study, nor did we detect a survival cost for adults that were actively brooding offspring. Our research illustrates the importance of understanding life‐history strategies and how they might influence relationships between adaptive habitat selection and demographic parameters. [ABSTRACT FROM AUTHOR]

Global climate change is increasing the frequency and intensity of weather extremes, including severe droughts in many regions. Drought can impact organisms by inhibiting reproduction, reducing survival and abundance, and forcing range shifts. For birds, considering temporal scale by averaging drought‐related variables over different time lengths (i.e., temporal grains) captures different hydrologic attributes which may uniquely influence food supplies, vegetation greenness/structure, and other factors affecting populations. However, studies examining drought impacts on birds often assess a single temporal grain without considering that different species have different life histories that likely determine the temporal grain of their drought response. Furthermore, while drought is known to influence bird abundance and drive between‐year range shifts, less understood is whether it causes within‐range changes in species distributions. Our objectives were to (a) determine which temporal grain of drought (if any) is most related to bird presence/absence and whether this response is species specific; and (b) assess whether drought alters bird distributions by quantifying probability of local colonization and extinction as a function of drought intensity. We used North American Breeding Bird Survey data collected over 16 years, generalized linear mixed models, and dynamic occupancy models to meet these objectives. Different bird species responded to drought at different temporal grains, with most showing the strongest signal at annual or near‐annual grains. For all drought‐responsive species, increased drought intensity at any temporal grain always correlated with decreased occupancy. Additionally, colonization/extinction analyses indicated that one species, the dickcissel (Spiza americana), is more likely to colonize novel areas within the southern/core portion of its range during drought. Considering drought at different temporal grains, along with hydrologic attributes captured by each grain, may better reveal mechanisms behind drought impacts on birds and other organisms, and therefore improve understanding of how global climate change impacts species and the landscapes they inhabit. [ABSTRACT FROM AUTHOR]

Disturbance is critical for the conservation of rangeland ecosystems worldwide and many of these systems are fire dependent. Although it is well established that restoring fire as an ecological process can lead to increased biodiversity in grasslands and shrublands, the underlying mechanisms driving community patterns are poorly understood for fauna in fire-prone landscapes. Much of this uncertainty stems from the paucity of studies that examine the effects of fire at scales relevant to organism life histories. We assessed the response of a non-migratory ground-dwelling bird to disturbance (i.e., prescribed fire) and environmental stochasticity over the course of a 4-yr period, which spanned years of historic drought and record rainfall. Specifically, we investigated the nesting ecology of Northern Bobwhite ( Colinus virginianus; hereafter Bobwhite) to illuminate possible avenues by which individuals respond to dynamic landscape patterns during a critical reproductive stage (i.e., nesting) in a mixed-grass shrubland in western Oklahoma, USA. We found that Bobwhites exhibited extreme plasticity in nest substrate use among time since fire categories ( TSF) and subsequently maintained high nest survival (e.g., 57-70%). Bobwhites were opportunistic in nest substrate use among TSF categories (i.e., 72% of nest sites in shrubs in 0-12 months post fire compared to 71% in herbaceous vegetation in >36 months post fire), yet nesting decisions were first filtered by similar structural components (i.e., vertical and horizontal cover) within the vicinity of nest sites regardless of TSF category. Despite being a non-migratory and comparatively less mobile ground-nesting bird species, Bobwhites adjusted to dynamic vegetation mosaics on a fire-prone landscape under stochastic climatic conditions that culminated in stable and high nest survival. Broadly, our findings provide a unique depiction of organism response strategies to fire at scales relevant to a critical life-stage, a topic that has been previously understudied and poorly understood. We also demonstrate how doing so can better inform conservation practices aimed at restoring fire regimes on grassland and shrubland landscapes. [ABSTRACT FROM AUTHOR]

Fire is a disturbance process that maintains the structure and function of grassland ecosystems while sustaining grassland biodiversity. Conversion of grasslands to other land uses coupled with altered disturbance regimes has greatly diminished the habitat available to many grassland-dependent species. These changes have been linked to declines in breeding bird populations, but may also be critical for migrating bird populations such as those shorebird species that depend on mesic grasslands during migration. We examined migratory shorebird use of burned grasslands in the southern Great Plains of North America using DISTANCE sampling to estimate and compare bird densities across recently burned and not recently burned landscapes (1-5 yr post fire). We conducted two surveys per week for 8-10 weeks along a 54-km route starting at the end of March and concluding in mid-May during 2014-2015. We encountered 2,509 total shorebirds in recently burned areas compared to 130 individuals in areas that were unburned. Fire was a major attractant for our three focal species with American Golden-plover ( Pluvialis dominica), Upland Sandpiper ( Bartramia longicauda), and Killdeer ( Charadrius vociferus) densities of 20.48, 11.09, and 26.09 birds/km2 in burned areas compared with 0.00, 1.27, and 0.92 birds/km2 in unburned areas, respectively. This research illustrates the importance of burned grassland for migrating shorebirds, a phenomenon that has largely gone unreported previously. Generally, these findings add to a body of knowledge that demonstrates the value of managing grasslands with historic disturbances that vary over space and time. The application of these findings should improve decision-making for shorebird conservation and provides evidence that prescribed fire planning should include consideration for breeding, transient, and non-breeding populations that vary in their temporal use of the landscape. [ABSTRACT FROM AUTHOR]

Deviations from typical environmental conditions can provide insight into how organisms may respond to future weather extremes predicted by climate modeling. During an episodic and multimonth heat wave event (i.e., ambient temperature up to 43.4°C), we studied the thermal ecology of a ground-dwelling bird species in Western Oklahoma, USA. Specifically, we measured black bulb temperature ( Tbb) and vegetation parameters at northern bobwhite ( Colinus virginianus; hereafter bobwhite) adult and brood locations as well as at stratified random points in the study area. On the hottest days (i.e., ≥39°C), adults and broods obtained thermal refuge using tall woody cover that remained on average up to 16.51°C cooler than random sites on the landscape which reached >57°C. We also found that refuge sites used by bobwhites moderated thermal conditions by more than twofold compared to stratified random sites on the landscape but that Tbb commonly exceeded thermal stress thresholds for bobwhites (39°C) for several hours of the day within thermal refuges. The serendipitous high heat conditions captured in our study represent extreme heat for our study region as well as thermal stress for our study species, and subsequently allowed us to assess ground-dwelling bird responses to temperatures that are predicted to become more common in the future. Our findings confirm the critical importance of tall woody cover for moderating temperatures and functioning as important islands of thermal refuge for ground-dwelling birds, especially during extreme heat. However, the potential for extreme heat loads within thermal refuges that we observed (albeit much less extreme than the landscape) indicates that the functionality of tall woody cover to mitigate heat extremes may be increasingly limited in the future, thereby reinforcing predictions that climate change represents a clear and present danger for these species. [ABSTRACT FROM AUTHOR]

Two fundamental issues in ecology are understanding what influences the distribution and abundance of organisms through space and time. While it is well established that broad-scale patterns of abiotic and biotic conditions affect organisms' distributions and population fluctuations, discrete events may be important drivers of space use, survival, and persistence. These discrete extreme climatic events can constrain populations and space use at fine scales beyond that which is typically measured in ecological studies. Recently, a growing body of literature has identified thermal stress as a potential mechanism in determining space use and survival. We sought to determine how ambient temperature at fine temporal scales affected survival and space use for a ground-nesting quail species ( Colinus virginianus; northern bobwhite). We modeled space use across an ambient temperature gradient (ranging from −20 to 38 °C) through a maxent algorithm. We also used Andersen-Gill proportional hazard models to assess the influence of ambient temperature-related variables on survival through time. Estimated available useable space ranged from 18.6% to 57.1% of the landscape depending on ambient temperature. The lowest and highest ambient temperature categories (<−15 °C and >35 °C, respectively) were associated with the least amount of estimated useable space (18.6% and 24.6%, respectively). Range overlap analysis indicated dissimilarity in areas where Colinus virginianus were restricted during times of thermal extremes (range overlap = 0.38). This suggests that habitat under a given condition is not necessarily a habitat under alternative conditions. Further, we found survival was most influenced by weekly minimum ambient temperatures. Our results demonstrate that ecological constraints can occur along a thermal gradient and that understanding the effects of these discrete events and how they change over time may be more important to conservation of organisms than are average and broad-scale conditions as typically measured in ecological studies. [ABSTRACT FROM AUTHOR]

Species occurrences have multiple ecological states that may strongly influence community analysis and inference. This may be especially true in freshwater systems where many animals have complex life cycles with adult dispersal and juvenile resident stages., The effects of ecological state variation on standard empirical approaches are largely unknown. Here, we analysed the effects of natal resident versus non-natal immigrant species occurrence on community-level environmental gradient modelling and spatial-environmental hypothesis testing using adult dragonflies and damselflies as model taxa., Resident and total (resident + immigrant) occurrences of these taxa responded to different sets of environmental variables and resident occurrences reduced model selection uncertainty in 75% of test cases., Effects of environmental gradients, spatial gradients or both were observed in residents but not immigrants, and supported predictions of dispersal limitation and niche-based species sorting often implicated for structuring freshwater communities., These results indicate that resident-only analysis of the dispersal stage should improve multi-model inference and detection of spatial-environmental effects in freshwater community ecology. The species resident-immigrant dichotomy neglects population dynamics and individual variation yet apparently marks an ecologically significant boundary that scales up to influence community-level occurrence patterns. [ABSTRACT FROM AUTHOR]

1. Grasslands world-wide provide a host of ecosystem services. In particular, these grasslands serve as biodiversity repositories for a myriad of imperilled animal species. One such group is grassland birds, which have experienced significant declines, predominantly caused by extensive loss and degradation of native grasslands. Rangeland management that promotes increasing and sustaining livestock production through reducing the inherent, disturbance-driven variability that historically occurred in grasslands is considered a major contributing factor to these declines. 2. An alternative approach to this homogeneous management paradigm attempts to restore a shifting mosaic of disturbance patches across the landscape through the spatial and temporal interactions of fire and grazing (i.e. pyric herbivory). Application of pyric herbivory through patch-burn grazing increases overall habitat heterogeneity, likely a critically important factor in maintaining and enhancing grassland bird populations. 3. We compared reproductive rates and estimates of fecundity of three grassland birds nesting in grasslands maintained by traditional and patch-burn grazing management paradigms in the Southern Great Plains of North America. Additionally, we used a sensitivity analysis approach to assess population stability (i.e. λ = 1) and source–sink population dynamics under the two management practices. 4. Nest survival for dickcissels Spiza americana and grasshopper sparrows Ammodramus savannarum was higher in patch-burned grasslands than in traditionally managed grasslands, while nest survival for eastern meadowlarks Sturnella magna was higher in traditionally managed grasslands than in patch-burned grasslands. 5. Dickcissels and grasshopper sparrows responded positively to patch burning with source habitats occurring over a wider range of survival rates under patch burning than traditional management, while no clear pattern emerged in source–sink dynamics of eastern meadowlarks. 6. Synthesis and applications. Management strategies such as patch-burn grazing offer opportunities to restore landscape heterogeneity to benefit bird communities while maintaining livestock production goals. Applying patch-burn grazing to rangelands can increase productivity of grassland birds and could be effective for reversing the decline of grassland birds by providing source habitats more consistently than traditional rangeland management. Our results emphasize the utility of using sensitivity analyses to determine source–sink population dynamics when evaluating management practices. However, land managers should consider that source–sink models have shortcomings and designation of a habitat as a sink does not necessarily mean the habitat has low conservation value. [ABSTRACT FROM AUTHOR]

To study population dynamics of Xanthomonas citri subsp. citri (Xcc) in citrus canker lesions on fruit, a needle-free injector was used for infiltration of bacterial inoculum into fruit in situ on mature 'Ruby Red' grapefruit ( Citrus paradisi Macf.) trees in Florida. Inoculations of Xcc at 105 colony-forming units (cfu) per ml were conducted in 2012 and 2013 on attached fruit varying from 15 mm to 90 mm in diameter. Inoculations were repeated every 2-3 weeks until the fruit were no longer injectable. On fruit less than 40 mm in size, erumpent lesions formed within 2 weeks of inoculation and expanded 1-9 mm in diameter from 30 to 120 days postinoculation (dpi). Xcc populations in lesions were 6-8 log cfu per lesion at 30 dpi and maintained this population up to 90 dpi. By 120 dpi, Xcc populations declined 1-3 log units as rainfall and temperature decreased in September-October. Xcc populations declined to ~3 log cfu per lesion after 120 dpi in November 2012 and 2013, whereas the population resurged to 5 log cfu per lesion after 180 dpi in January-February 2014. [ABSTRACT FROM AUTHOR]

Temperature is highly variable across space and time at multiple scales, shapes landscape pattern, and dictates ecological processes. While our knowledge of ecological phenomena is vast relative to many landscape metrics, thermal patterns which shape landscape mosaics are largely unknown. To address this disconnect, we investigated the thermal landscape by measuring black bulb temperature (Tbb) at intervals as small as 15 min across 3 yr in a mixed-grass shrub vegetation community. We found that the thermal landscape was highly heterogeneous displaying a prevalence for thermal extremes (i.e., Tbb > 50°C) and that Tbb was driven by the synergism of environmental, terrain, and vegetation factors. Specifically, variation of Tbb on the landscape was best predicted by the inclusion of ambient temperature (Tair), solar radiation (Srad), low woody cover, and tall woody cover as variables. Moreover, models of single vegetation parameters (i.e., bare ground, low woody, or tall woody cover) each had greater relative importance than those containing a single terrain variable (i.e., slope or aspect) based on AIC, providing evidence that vegetation is a key driver of Tbb on the landscape. Within the thermally heterogeneous landscape, tall woody cover moderated Tbb by 10°C more than bare ground, herbaceous, or low woody cover during peak diurnal heating (14:00), and was the only cover type that remained <50°C on average. Given that tall woody cover comprises only about 7% of the landscape in our study, these findings have direct conservation implications for species inhabiting shrub communities, specifically that the distribution of tall woody cover is a spatially limited but key predictor of potential thermal refugia on the landscape. Our findings also demonstrate that local interactions between vegetation and temperature can create thermal patterns that shape dynamic landscape mosaics across space and time. Furthermore, we show that structural heterogeneity can maximize thermal complexity across landscapes which can provide greater potential thermal options for organisms. However, our modeled climate projections suggest that far greater thermal extremes will be possible across increasingly larger swaths of the landscape in the future, making assessments and quantifications of thermal landscapes increasingly critical. [ABSTRACT FROM AUTHOR]

The fact that species have resident (autochthonous) or immigrant (allochthonous) status at any given locality may have strong implications for ecological analysis., We used wetlands and adult odonates as a model system to evaluate the resident-immigrant dichotomy for two modes of community analysis: (1) grouping sites based on species compositional variation and (2) identifying metacommunity structure. We tested a hypothesis of gradient-structured (non-random) resident occurrence versus unstructured (random) immigrant occurrence in the metacommunity context and predicted the resident occurrence would more effectively partition community variation and produce stronger site groupings than total (resident + immigrant) occurrence., Site group classification after fractioning out resident occurrence consistently and in some cases dramatically outperformed total occurrence. Resident damselflies produced the strongest classifications, which we attribute to greater dispersal limitation, environmental sorting or both., As predicted only the resident occurrence led to identifiable metacommunity structures, primarily Clementsian-style turnover. This suggests the resident occurrence is gradient-driven with species responding similarly to abiotic filters, whereas immigrant occurrence is more opportunistic and random., The resident-immigrant dichotomy appears to have strong influence on quantitative classification of sites and metacommunities, and species composition of resident adult damselflies is potentially useful for differentiating and indicating site groups of non-forested freshwater wetlands. [ABSTRACT FROM AUTHOR]

The aging and deterioration of water distribution systems in cities worldwide result in more frequent water main breaks, dramatic pavement failures, and flooding damage. This study examines the consequences of water main breaks, especially the failure of street pavements caused by the pressure of leaking water and the erosion of pipe bedding. It accounts for various types of pressure releases and encompasses abrupt to slow water discharges. It also considers the formation of cavities under street pavements caused by longstanding leaks. Although simplified, the study covers many geometries and properties of pipes and bedding materials in urban infrastructures. By estimating the consequences of water main breaks, the analysis intends to prompt more proactive infrastructure asset planning. [ABSTRACT FROM AUTHOR]

ABSTRACT Rangeland birds in the Southern High Plains, USA evolved within a context of fire and grazing (i.e., pyric herbivory), a disturbance regime that played a dominant role in shaping rangelands in this region but has been absent since the 1880s. A management technique known as patch-burn grazing was used to mimic the heterogeneity in vegetation created by the historical disturbance regime of fire and grazing in sand sagebrush ( Artemisia filifolia) rangelands. We compared nest survival of Cassin's sparrows ( Peucaea cassinii), field sparrows ( Spizella pusilla), and lark sparrows ( Chondestes grammacus); species richness; and densities of 11 bird species between rangelands managed with patch-burn grazing and rangelands managed with traditional management (i.e., seasonal grazing) in Oklahoma from 2006 to 2008. Estimates of nest survival were similar between patch-burn and traditional pastures (Cassin's sparrows: 51% and 57%; field sparrows: 18% and 22%; and lark sparrows: 14% and 12%, patch-burn and traditional, respectively). Species richness was higher in patch-burn pastures compared to traditionally managed pastures. Densities of the majority of avian species (73%) were similar between treatments; however, lark sparrow densities were 5 times more abundant in patch-burn pastures and grasshopper sparrows ( Ammodramus savannarum) and brown-headed cowbirds ( Molothrus ater) were >3 times more abundant on traditional pastures. Our results suggest that introducing patch-burn grazing management to sand sagebrush rangelands is not detrimental to nesting shrubland birds, and the creation of heterogeneity through patch-burn grazing can increase avian species diversity. Furthermore, some species such as lark sparrows may benefit from patch-burn grazing. Patch-burn management may be an important tool to assist in the recovery of biodiversity in this ecosystem. © 2014 The Wildlife Society. [ABSTRACT FROM AUTHOR]

The article focuses on a study that examine the effectiveness of acellular pertussis vaccine in children. Study used collected notification, hospitalization and vaccine data of children to describe testing patterns. Study showed that numbers of pertussis tests performed for children increased between 2009 and 2010.

The article presents a case study of a 29-year-old woman Heterotopic ossification (HO) of the distal right femur and left shoulder. It informs that the patient was diagnosed and excision of the left lower limb mass with possible repair was made. It informs that HO is an ectopic lamellar bone formation and occurs in the areas of large joints including the shoulder, elbow, and hip.

Summary 1. Patterns of landscape heterogeneity are crucial to the maintenance of biodiversity in shrublands and grasslands, yet management practices in these ecosystems typically seek to homogenize landscapes. Furthermore, there is limited understanding of how the interaction of ecological processes, such as fire and grazing, affects patterns of heterogeneity at different spatial scales. 2. We conducted research in Artemisia filifolia (Asteraceae) shrublands located in the southern Great Plains of North America to determine the effect of restoring the fire-grazing interaction on vegetation structure. Data were collected for 3 years in replicated pastures grazed by cattle Bos taurus where the fire-grazing interaction had been restored (fire and grazing = treatment pastures) and in pastures that were grazed but remained unburned (grazing only, no fire = control pastures). The effect of the fire-grazing interaction on heterogeneity (variance) of vegetation structure was assessed at scales from 12·5 m2 to 609 ha. 3. Most measurements of vegetation structure within treatment pastures differed from control pastures for 1-3 years after being burned but were thereafter similar to the values found in unburned control pastures. 4. Treatment pastures were characterized by a lower amount of total heterogeneity and a lower amount of heterogeneity through time. 5. Heterogeneity of vegetation structure tended to decrease as the scale of measurement increased in both treatment and control pastures. There was deviation from this trend, however, in the treatment pastures that exhibited much higher heterogeneity at the patch scale (mean patch size = 202 ha) of measurement, the scale at which patch fires were conducted. 6. Synthesis and applications. Vegetation structure in A. filifolia shrublands of our study was readily altered by the fire-grazing interaction but also demonstrated substantial resilience to these effects. The fire-grazing interaction also changed the total amount of heterogeneity characterizing this system, the scale at which heterogeneity in this system was expressed and the amount of heterogeneity expressed through time. Land managers seeking to impose a shifting mosaic of heterogeneity on this vegetation type can do so by restoring the fire-grazing interaction with potential conservation benefits similar to what has been achieved in other ecosystems where historic cycles of disturbance and rest have been restored. [ABSTRACT FROM AUTHOR]

Objective: To describe the epidemiology of infectious syphilis among Aboriginal and Torres Strait Islander (Indigenous) people in Australia.Design and Setting: We assessed trends in national infectious syphilis notification rates from 2005 to 2009 using Poisson regression, with a focus on geographic and demographic differences by Indigenous status. We compared Indigenous and non-Indigenous rate ratios over the study period and summarised the annual changes (summary rate ratio).Main Outcome Measures: Crude notification rates and summary rate ratios by Indigenous status, jurisdiction, sex, age group and area of residence.Results: From 2005 to 2009, in the Indigenous population, there was a substantial decline in the notification rate for infectious syphilis nationally; as well as in the following subgroups: females, 15-29 year olds, and people living in outer regional and remote areas in the Northern Territory and Queensland. In contrast, there was a significant (P < 0.001) upward trend in the notification rate in the non-Indigenous population nationally; as well as in males, in people aged 20 years and over, and in residents of metropolitan and regional areas, New South Wales, Queensland, South Australia, Victoria and Western Australia. The highest summary rate ratios were seen in remote/very remote areas (86.33; 95% CI, 57.45-129.74), in 15-19 year olds (64.65; 95% CI, 51.12-81.78), in females (24.59; 95% CI, 19.73-30.65), and in Western Australia (23.89; 95% CI, 19.82-28.82).Conclusion: These data demonstrate that Australia has two distinct patterns of infectious syphilis: a substantially declining occurrence in Indigenous remote communities and an increasing incidence in males residing in urban and regional areas. Given the decline in notification rates in Indigenous remote communities, now might be the right time to move toward eliminating infectious syphilis from Indigenous communities. [ABSTRACT FROM AUTHOR]

Soil invertebrate communities are fundamental components of wet meadow ecosystems. We compared soil invertebrate biodiversity between restored and native wet meadows to assess the effectiveness of restoration practices. Biodiversity and biomass were measured in 2002 and 2003 from four native and three restored sites located along a 100-km stretch of the Platte River in south-central Nebraska. The sites ranged in age from 3 to 6 years since restoration. Samples were collected during May, July, and September each year. Soil temperature, soil moisture, percent litter cover, and root mass were measured at each site. Twelve 20 × 20 × 25–cm soil blocks were extracted at each site; soil was washed through a 1-mm sieve; and invertebrates were identified, counted, and weighed. Native sites had higher Shannon and Simpson diversity values and contained greater invertebrate biomass than restored sites. Five invertebrate taxa (isopods, scarab beetles, click beetles, earthworms, and ants) were collected with enough frequency to assess restoration effects on their occurrence. Of these, only ants occurred more frequently in restored sites. Restored sites generally had less litter cover, lower root mass, lower soil moisture, and higher soil temperature than native sites. Current restoration practices may not be completely effective at returning sites to native conditions. Physical reconstruction of wet meadow topography and high-diversity reseeding may not be adequate to fully restore soil invertebrate communities, even over extended periods of time. [ABSTRACT FROM AUTHOR]

Grassland birds have declined more than any other North American habitat-associated bird community. Because most species of grassland birds evolved within heterogeneous landscapes created by the interaction of fire and grazing, traditional rangeland management that promotes homogeneity, including annual dormant-season burning combined with early-intensive grazing, might be partly responsible for these declines, especially in some regions of the Great Plains, USA. Recently, an alternative grassland management practice known as patch-burning has been promoted as a means of restoring heterogeneity to grasslands by mimicking the grazing--fire interaction that once occurred on the prairie before European settlement. From 2003 to 2004, we examined effects of patch-burning and traditional management (annual burning followed by early-intensive grazing) on the reproductive success of dickcissels (Spiza americana) in tallgrass prairie in Oklahoma. We monitored 296 dickcissel nests and found that dickcissel nesting phenology differed between traditional and patch-burned pastures. Specifically, dickcissels tended to initiate their nests later in the traditional pasture. Mean number of eggs laid and fledglings produced were similar between the treatments, but nest densities were higher in traditional pastures. Predation was the predominant cause of nest failure and was higher in traditional pastures than in patch-burned pastures. Brown-headed cowbird (Molothrus ater) parasitism was higher in traditional pastures than in patch-burned pastures. Overall, dickcissel nest success was higher in patch-burned pastures than in traditional pastures. The positive response of dickcissel nest success to patch-burn management provides further evidence that this practice can be a useful tool for grassland bird conservation. By creating a mosaic of different stature vegetation, patch-burn management enhances productivity of grassland bird species by providing a refuge area in the unburned patches that affords dickcissels and other nesting grassland birds some protection from the direct (e.g., trampling) and indirect (e.g., cowbird parasitism and predation) effects of grazing, which are not available under traditional management. Patch-burn management should be encouraged as a conservation strategy for grassland birds throughout the Great Plains. [ABSTRACT FROM AUTHOR]

Progress in analysing the cellular functions of many structural proteins has accelerated through the use of confocal microscopy together with transient gene expression. Several methods for transient expression have been developed in the past few years, but their application has seen limited success beyond a few tractable species and tissues. We have developed a simple and efficient method to visualize fluorescent proteins in Arabidopsis root epidermis using co-cultivation of seedlings with Agrobacterium rhizogenes. The method is equally suitable for transient gene expression in other species, including Thellungiella, and can be combined with supporting molecular and biochemical analyses. The method promises significant advantages for study of membrane dynamics, cellular development and polar growth in root hairs without interference in the development of the plant. Since the method targets specifically the root epidermis, it also offers a powerful tool to approach issues of root–rhizosphere interactions, such as ion transport and nutrient acquisition. As a proof of principle, we carried out transfections with fluorescent markers for the plasma membrane (NpPMA2–GFP, Nicotiana plumbaginifolia L. Plasma Membrane H+-ATPase 2), the endoplasmic reticulum (YFP–HDEL), and the Golgi apparatus (sialyl transferase–GFP) to trace their distribution in growing Arabidopsis root hairs and epidermis. The results demonstrate that, in Arabidopsis root hairs, movement of the Golgi is faster than previously reported for tobacco leaf epidermal cells, consistent with the high secretory dynamics of the tip growing cell; they show a pattern to the endoplasmic reticulum within the cytoplasm that is more diffuse than found in tobacco leaf epidermis, and they confirm previous findings of a polarized distribution of the endoplasmic reticulum at the tip of growing root hairs. [ABSTRACT FROM AUTHOR]

The article cites that increasing spatial and temporal heterogeneity of disturbance in grasslands increases variability in vegetation structure that results in greater variability at higher trophic levels. Management that creates a shifting mosaic using spatially and temporally discrete disturbances in grasslands can be a useful tool in conservation. In the case of North American tallgrass prairie, discrete fires that capitalize on preferential grazing behavior of large ungulates promote a shifting mosaic of habitat types that maintain biodiversity and agricultural productivity.

Presents a study which determined migrant-shorebird species compositions, abundances, migration chronologies, use of habitats, and feeding ecologies in the Playa Lakes Region of Texas during spring and fall migration. Description of the study area; Results; Management and research implications.