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Cheatgrass (Bromus tectorum) has increased the extent and frequency of fire and negatively affected native plant and animal species across the Intermountain West (USA). However, the strengths of association between cheatgrass occurrence or abundance and fire, livestock grazing, and precipitation are not well understood. We used 14 years of data from 417 sites across 10,000 km2 in the central Great Basin to assess the effects of the foregoing predictors on cheatgrass occurrence and prevalence (i.e., given occurrence, the proportion of measurements in which the species was detected). We implemented hierarchical Bayesian models and considered covariates for which > 0.90 or

Tick-borne diseases are becoming increasingly prevalent world-wide. This is likely due in part to land-cover change, particularly forest fragmentation, but this evidence is largely limited to Lyme disease. It is unknown whether this is generalizable to other, emergent tick-borne pathogens. Motivated by hypotheses regarding landscape context and vertebrate hosts, we asked how landscape context, namely habitat amount, quality, and fragmentation, is related to the distribution of Ehrlichia chaffeensis, a tick-borne pathogen of increasing concern, and the interannual occupancy dynamics of its vector, the lone star tick (Amblyomma americanum). We collected nymphal ticks from 130 plots in southeastern Virginia, U.S., for 5 years and tested for E. chaffeensis via targeted PCR. We derived metrics of landscape context from Landsat data and related these to pathogen prevalence and tick turnover using hierarchical Bayesian models. Landscape context was associated with both pathogen prevalence and tick turnover. Pathogen prevalence was negatively associated with total forest landcover, coniferous forest landcover, and forest edge density. Tick turnover was positively associated with coniferous landcover and with an interaction between total forest landcover and edge. This interaction was such that turnover was predicted to be lowest in small contiguous forests, and highest in small fragmented forests. Landscape context affects E. chaffeensis prevalence and occupancy dynamics of its tick host, though these processes appear decoupled. We hypothesize that pathogen prevalence may be more driven by reservoir host movement and social behavior and tick dynamics are more driven by host population density.

The concept of ecological integrity has been applied widely to management of aquatic systems, but still is considered by many to be too vague and difficult to quantify to be useful for managing terrestrial systems, particularly across broad areas. Extensive public lands in the western United States are managed for diverse uses such as timber harvest, livestock grazing, energy development, and wildlife conservation, some of which may degrade ecological integrity. We propose a method for assessing ecological integrity on multiple-use lands that identifies the components of integrity and levels in the ecological hierarchy where the assessment will focus, and considers existing policies and management objectives. Both natural reference and societally desired environmental conditions are relevant comparison points. We applied the method to evaluate the ecological integrity of shrublands in Nevada, yielding an assessment based on six indicators of ecosystem structure, function, and composition, including resource- and stressor-based indicators measured at multiple scales. Results varied spatially and among indicators. Invasive plant cover and surface development were highest in shrublands in northwest and southeast Nevada. Departure from reference conditions of shrubland area, composition, patch size, and connectivity was highest in central and northern Nevada. Results may inform efforts to control invasive species and restore shrublands on federal lands in Nevada. We suggest that ecological integrity assessments for multiple-use lands be grounded in existing policies and monitoring programs, incorporate resource- and stressor-based metrics, rely on publicly available data collected at multiple spatial scales, and quantify both natural reference and societally desired resource conditions.

Panoquina panoquin (Salt Marsh Skipper) is an understudied butterfly that resides primarily in coastal salt marshes throughout the southern Atlantic and Gulf of Mexico. Based on our review of online databases and published literature, this species may use several different host plants, though Distichlis spicata (Saltgrass) is most commonly cited. While surveying salt marsh butterfly communities in southeastern Virginia in 2019, we observed 25 oviposition events from female Salt Marsh Skippers, all of which laid their eggs exclusively on Spartina alterniflora (Smooth Cordgrass). This is the first conclusive record of the Salt Marsh Skipper using this species of grass for egg laying. Our observations broaden the understanding of Salt Marsh Skipper habitat requirements and therefore inform conservation efforts for this species in the face of degradation of salt marshes throughout its range.

We tracked 47 Wood Thrushes (Hylocichla mustelina) using radio telemetry over 2 breeding seasons in Virginia, USA. Here we present 2 noteworthy observations from this effort. First, we recorded one adult male with synchronous tail replacement in postbreeding molt during tracking from the early breeding season until the fall migration. Synchronous tail molt is seldom documented in Passeriformes and may have consequences for behavior and habitat use during this period of reduced mobility. Second, we recorded a widower male providing parental care by feeding young for nearly the entire nestling period. These observations highlight both the vulnerability of the Wood Thrush immediately following the breeding season and its potential reproductive resilience in the case of mate loss.

To forestall the current rate of global extinction, we need to identify strategies that successfully recover species. In the last decade, the recovery record for the United States Endangered Species Act (ESA) has improved. Our aim was to review federal delisting documents for recovered species and quantify patterns in taxonomy, history of threats, policy, funding and actions that are associated with species recovery. In comparison to species still listed, the average recovered species was a vertebrate, had been listed longer under the ESA, was exposed to a lower number of threats at the time of listing, and received relatively higher levels of funding. Based on our review, we suggest the following strategies to improve species recovery: provide more time for ESA protection, allocate more funding for recovery, maintain environmental regulations that facilitate recovery, establish more private landowner agreements, and increase the area of protected lands.

Ehrlichia chaffeensis (Rickettsiales: Anaplasmatacae), an understudied bacterial pathogen emerging in the eastern United States, is increasing throughout the range of its vector, the lone star tick [Amblyomma americanum, L. (Acari: Ixodidae)]. To mitigate human disease risk, we must understand what factors drive E. chaffeensis prevalence. Here, we report patterns of E. chaffeensis prevalence in southeastern Virginia across 4 yr and ask how seasonal weather patterns affect variation in rates of E. chaffeensis occurrence. We collected A. americanum nymphs at 130 plots across southeastern Virginia in 2012, 2013, 2015, and 2016, and used polymerase chain reaction and gel electrophoresis to test for the presence of E. chaffeensis DNA. Prevalence estimates varied among years, ranging from 0.9% to 3.7%, and persistence of E. chaffeensis occurrence varied across space, with some sites never testing positive, and one site testing positive every year. Using generalized linear mixed-effects models, we related E. chaffeensis occurrence to temperature, humidity, vapor-pressure deficit, and precipitation during seasons up to 21 mo prior to sampling. Surprisingly, all support was lent to a positive effect of temperature during the previous fall and winter (i.e., prior to the nymphs' hatching), which we hypothesize to influence reservoir host population dynamics through changes to mortality or natality. Although further work is necessary to truly elucidate the mechanisms at play, our study shows E. chaffeensis distribution to be very dynamic across multiple dimensions, demanding broad concerted monitoring efforts that can consider both space and time.

We developed a transferable method to identify indicator species and environmental variables that explain considerable variation in species richness. We applied this method to birds and butterflies and conducted novel, rigorous external evaluations of the spatial and temporal transferability of such indicator species. We collected data in the central Great Basin (Lander, Nye, and Eureka Counties, Nevada) and western Great Basin (Mono County, California and Mineral, Douglas, and Lyon Counties, Nevada), United States. We used Bayesian model selection to identify sets of five species that best explained observed variation in species richness of the same or the other taxonomic group in either subregion. We then built random forest models that included only the five identified indicator species and externally tested these models with new data from the other subregion (central or western Great Basin) or a later time in the same subregion. We compared the predictive accuracy of indicator-species only models to that of models based on environmental variables or on both indicator species and environmental variables. In external evaluations, models based on same-taxon indicator species predicted 34–52% of the variation in species richness of birds and 40–70% of the variation in species richness of butterflies. Comparable models based on environmental variables predicted 11–46% of the variation in species richness of birds and 12–67% of the variation in species richness of butterflies. Models based on same-taxon indicator species predicted more variation in species richness than those based on environmental variables in seven of eight cases. Our results suggested that the predictive accuracy and spatial and temporal transferability of models based on indicator species can exceed that of models based on environmental variables. If mechanistic responses to environmental change are consistent through time, tracking the occurrence of a subset of an assemblage during periods of environmental change may allow inference to species richness of the assemblage.

Cheatgrass (Bromus tectorum L.) presence in the Great Basin is associated with an increase in fire frequency and size, likely due to increased spatial continuity of fine fuel biomass. Measurements of the extent and cover of cheatgrass are steadily improving, but the strength of the relationship between cover and aboveground biomass (AGB) is unclear. An allometric equation that can reliably convert cover to AGB of cheatgrass would allow for improved incorporation of regional estimates of cover into models of fire activity, carbon storage, and net primary productivity, all of which rely on biomass. We measured cover and AGB of cheatgrass at 60 locations in the north-central Great Basin and used these measurements to model the relationship. We found a strong, linear relationship between the percent cover and AGB, which was improved after square root transformation of both cover and AGB, and after incorporating the number of days after peak NDVI that the biomass and cover were measured. These results show that AGB of cheatgrass can be reliably estimated from cover. It is likely that allometric equations based on cover will be effective for other grass species, but care must be taken to account for phenology (e.g., peak NDVI) in the estimation.

Pinon ( Pinus spp.) and juniper ( Juniperus spp.) woodlands have been expanding their range across the intermountain western United States into landscapes dominated by sagebrush ( Artemisia spp.) shrublands. Management actions using prescribed fire and mechanical cutting to reduce woodland cover and control expansion provided opportunities to understand how environmental structure and changes due to these treatments influence bird communities in pinon-juniper systems. We surveyed 43 species of birds and measured vegetation for 1–3 years prior to treatment and 6–7 years post-treatment at 13 locations across Oregon, California, Idaho, Nevada, and Utah. We used structural equation modeling to develop and statistically test our conceptual model that the current bird assembly at a site is structured primarily by the previous bird community with additional drivers from current and surrounding habitat conditions as well as external regional bird dynamics. Treatment reduced woodland cover by >5% at 80 of 378 survey sites. However, habitat change achieved by treatment was highly variable because actual disturbance differed widely in extent and intensity. Biological inertia in the bird community was the strongest single driver; 72% of the variation in the bird assemblage was explained by the community that existed seven years earlier. Greater net reduction in woodlands resulted in slight shifts in the bird community to one having ecotone or shrubland affinities. However, the overall influence of woodland changes from treatment were relatively small and were buffered by other extrinsic factors. Regional bird dynamics did not significantly influence the structure of local bird communities at our sites. Our results suggest that bird communities in pinon-juniper woodlands can be highly stable when management treatments are conducted in areas with more advanced woodland development and at the level of disturbance measured in our study.

The tendency by individual birds to return to winter sites in subsequent years can be important in assessing the potential influence of habitat changes during the nonbreeding period. We recaptured five Brewer's (Spizella breweri), seven sagebrush (Artemisiospiza nevadensis), and three black-throated (Amphispiza bilineata) sparrows from 1–3 subsequent years at the same winter location following their initial capture. Two Brewer's and one sagebrush sparrow returned to the same winter location at least 4 y after their initial capture. Levels of feather deuterium indicated that birds captured together on winter sites had different breeding ranges. Although individuals of these species returned to specific sites used in previous years, the low recapture rate suggests that wintering individuals may use an itinerant strategy adapted to seasonal food resources.

Consumption of understory foliage by abundant ungulates can reshape forest structure and thus induce corresponding ecosystem changes. In forest songbirds, a negative response to deer browsing was documented for species that use understory foliage, although this association remains poorly understood at the community level. Such knowledge is especially important in eastern North America where deer populations have recently increased substantially. Our primary objective was to examine correlations between deer and songbirds in coastal Virginia (n = 92 sites, 2010–2013), a region with heavy forest fragmentation and abundant deer. The secondary objectives were to compare coastal surveys to an inland region (n = 99 sites, 2012) with fewer deer and lower fragmentation, and to explore links between fragmentation and deer. We predicted that densities of songbirds that use understory foliage (“deer-sensitive”) would correlate negatively with deer fecal pellets – our measure of relative deer use. The estimate of median pellets inland (0 ha−1, range 0–19,600 pellets ha−1) was significantly lower than on the coast (2,014 ha−1, range 0–28,193 ha−1). We found a negative correlation with deer-sensitive birds on the coast (rs = −0.35, P = 0.002), whereas inland, no correlation was evident. Coastal sites had approximately twice as much fragmented forest, which favors deer. Of 26 songbirds in our species-level analysis, we found negative correlations for three species, including one of high conservation concern. These results are consistent with the hypothesis that habitat modification by over-abundant deer promotes measurable changes in bird communities, with conservation implications for declining songbirds.

Understanding temporal variation of threats that cause species endangerment is a key to understand conservation strategies needed to improve species recovery. We assessed temporal variation in the threats to species listed under the United States Endangered Species Act (ESA) as identified by the United States Fish and Wildlife Service (USFWS) and National Marine Fisheries Service (NMFS). Based on initial review of ESA listing decisions and literature, we identified six overarching threat categories: habitat modification, overutilization, pollution, species–species interaction, demographic stochasticity, and environmental stochasticity. We screened listing decision documents to determine threat occurrence (i.e., presence/absence of a given threat in a listing decision) for each threat category for all species listed between 1975 and 2017. We evaluated how the number of threats and specific threat occurrences changed over the past four decades. We found that the number of threats per listing decision increased more than twofold from an average of 1.5 (95% CI: 1.3–1.7) threats in 1975 to 3.7 (95% CI: 3.4–4.0) threats in 2017. Threat occurrence increased for habitat modification, environmental stochasticity and species–species interaction, while it decreased for overutilization since 1975 and for demographic stochasticity and pollution since the mid‐2000s. The documented increase in number of threats at time of listing may be due to a growing human population exerting increased pressure on species persistence, improved scientific advancement in understanding factors influencing species endangerment, or prolonged time taken for more recent species to be listed under the ESA. We believe that key federal and state governmental regulations have resulted in a documented decrease in overutilization, demographic stochasticity, and pollution, and we recommend large‐scale strategies combined with local planning efforts to address the growing threats of habitat loss, environmental stochasticity, and species–species interaction.

Increasingly, point-count data are used to estimate occupancy, the probability that a species is present at a given location; occupancy accounts for imperfect detection, the probability that a species is detected given that it is present. To our knowledge, effects of sampling duration on inferences from models of bird occupancy have not been evaluated. Our objective was to determine whether changing count duration from 5 to 8 min affected inferences about the occupancy of birds sampled in the Chesapeake Bay Lowlands (eastern United States) and the central and western Great Basin (western United States) in 2012 and 2013. We examined the proportion of species (two doves, one cuckoo, two swifts, five hummingbirds, 11 woodpeckers, and 122 passerines) for which estimates of detection probability were ≥ 0.3. For species with single-season detection probabilities ≥ 0.3, we compared occupancy estimates derived from 5- and 8-min counts. We also compared estimates for three species sampled annually for 5 yr in the central Great Basin. Detection probabilities based on both the 5- and 8-min counts were ≥ 0.3 for 40% ± 3% of the species in an ecosystem. Extending the count duration from 5 to 8 min increased the detection probability to ≥ 0.3 for 5% ± 0.5% of the species. We found no difference in occupancy estimates that were based on 5- versus 8-min counts for species sampled over two or five consecutive years. However, for 97% of species sampled over 2 yr, precision of occupancy estimates that were based on 8-min counts averaged 12% ± 2% higher than those based on 5-min counts. We suggest that it may be worthwhile to conduct a pilot season to determine the number of locations and surveys needed to achieve detection probabilities that are sufficiently high to estimate occupancy for species of interest.

Aim We explored the extent to which occupancy of butterflies within three biogeographic regions could be explained by vegetation structure and composition, topography and other environmental attributes; whether results were consistent among regions; and whether assumptions of closure were met with assemblage-level sampling designs. Location Chesapeake Bay Lowlands (Virginia), central Great Basin (Nevada) and western Great Basin (Nevada and California) (all USA). Methods We applied single-season occupancy models that either assumed closure or relaxed the closure assumption to data from 2013 and 2014 for 13–15 species in each region. Results Maximum single-year estimates of detection probabilities ranged from 0.14 to 0.99, and single-year occupancy from 0.28 to 0.98. The assumption of closure was met for a maximum of 54% of the species in a given region and year. Detection probabilities of > 90% of the species in each region increased as the categorical abundance of nectar or mud increased. Measures of the dominance or abundance of deciduous woody species and structural heterogeneity were included in the greatest number of occupancy models for the Chesapeake Bay Lowlands, which may in part reflect the intensity of browsing by white-tailed deer (Odocoileus virginianus). Elevation and precipitation were prominent covariates in occupancy models for Great Basin butterflies. Main conclusions Because occupancy models do not rely on captures or observations of multiple individuals in a population, they potentially can be applied to a relatively high proportion of the species in an assemblage. However, estimation of occupancy is complicated by taxonomic, temporal and spatial variation in phenology. In multiple, widely divergent ecosystems, all or some associations between covariates and detection probability or occupancy for at least one-third of the species could not be estimated, often because a given species rarely was detected at locations with relatively low or high values of a covariate. Despite their advantages, occupancy models may leave unexplained the environmental associations with the distributions of many species.

Phthalates have detrimental effects on health and have been shown to dysregulate the immune system of mammals, birds, and fish. We recently reported that di(2-ethylhexyl) phthalate exposure reduces the abundance and inhibits the proliferation of rainbow trout (Oncorhynchus mykiss) IgM(+) B lymphocytes and expression of secreted immunoglobulin heavy-chain mu transcripts in an in vitro culture system. We proposed that phthalates act as immunomodulators by modifying the normal B cell-activation pathways by accelerating B cell differentiation while suppressing plasmablast expansion, thus resulting in fewer IgM-secreting plasma cells. This hypothesis was tested here in an in vivo field study of juvenile Dolly Varden (Salvelinus malma) from a plastic-polluted lake in the Gulf of Alaska. Fish tissues were analyzed for both phthalate levels using liquid chromatography-coupled tandem mass spectrometry and for changes in immune gene expression using reverse transcriptase-real time polymerase chain reaction. Results showed that fish with higher tissue levels of di(2-ethylhexyl) phthalate, di(n-butyl) phthalate, and/or dimethyl phthalate expressed significantly fewer secreted and membrane-bound immunoglobulin heavy-chain mu and Blimp1 transcripts in their hematopoietic tissue. This suggests that in vivo uptake of phthalates in fish changes the expression of B cell-specific genes. Chronic exposure to phthalates likely dysregulates normal B-lymphoid development and antibody responses in salmonids and may increase susceptibility to infection. Given the conserved nature of B-lineage cells in vertebrate animals, other marine species may be similarly affected by chronic phthalate exposure.

This work was supported in part by a contract between BP Exploration (Alaska) Inc. and the University of California, Santa Barbara (E.F.), and by the North Slope Borough. Potential responses of marine mammals to anthropogenic underwater sound are usually assessed by researchers and regulators on the basis of exposure to a single, relatively loud sound source. However, marine mammals typically receive sounds from multiple, dynamic sources. We developed a method to aggregate modeled sounds from multiple sources and estimate the sound levels received by individuals. To illustrate the method, we modeled the sound fields of 9 sources associated with oil development and estimated the sound received over 47 d by a population of 10 000 simulated bowhead whales Balaena mysticetus on their annual migration through the Alaskan Beaufort Sea. Empirical data were sufficient to parameterize simulations of the distribution of individual whales over time and their range of movement patterns. We ran 2 simulations to estimate the sound exposure history and distances traveled by bowhead whales: one in which they could change their movement paths (avert) in response to set levels of sound and one in which they could not avert. When animals could not avert, about 2% of the simulated population was exposed to root mean square (rms) sound pressure levels (SPL) ≥ 180 dB re 1 mu Pa, a level that regulators in the U.S. often associate with injury. When animals could avert from sound levels that regulators often associate with behavioral disturbance (rms SPL > 160 dB re 1 μPa)

Researchers have long recognized that the spatial distribution of animals relates to habitat requirements. In birds, despite recent advances in tracking techniques, knowledge of habitat needs remains incomplete for most species. Using radio telemetry, we quantified the relative space use of 37 Wood Thrush (Hylocichla mustelina) males, captured over 2 years (2013, 2014) on their breeding grounds in coastal Virginia. Following tracking, we collected data on prey availability (n = 370 plots) and habitat structure (n = 222 plots) within bird home ranges, and modeled bird utilization distribution with both sets of variables using mixed models. Our objectives were to (a) determine the relative importance of habitat structure and prey availability for bird use, (b) identify specific resources that related to bird utilization distribution, (c) test the hypothesis that soil moisture explained prey availability, and (d) evaluate models by determining whether model-identified conditions agreed with data at ...

The behavior of roosting birds has received little attention from ornithologists, despite its importance for understanding the complete avian circadian cycle. We examined the spatial arrangement of roosts in relation to diurnal home ranges for the declining Wood Thrush (Hylocichla mustelina) on its breeding grounds in coastal Virginia, USA. To our knowledge, this is the first broad description of roosting ecology for a North American migratory passerine during the breeding season. The primary objective of this study was to determine whether roost sites and diurnal use areas overlapped. Secondly, using LiDAR, we tested the hypothesis that birds roosted at sites with higher local vegetation density than random points. Lastly, we explored the effect of nest status on the roosting patterns of pairs. We tracked 37 radio-tagged males to construct 95% kernel diurnal home ranges. In 10 home ranges we also tagged the female mates. Both sexes were tracked at night to roosting locations. Of 74 male roosts, ...

Few studies have examined the patterns of co-occurrence between diurnal birds such as woodpeckers and nocturnal birds such as owls, which they may facilitate. Flammulated Owls (Psiloscops flammeolus) and Northern Saw-whet Owls (Aegolius acadicus) are nocturnal, secondary cavity-nesting birds that inhabit forests. For nesting and roosting, both species require natural cavities or, more commonly, those that woodpeckers create. Using day and nighttime broadcast surveys (n = 150 locations) in the Rocky Mountain biogeographic region of Idaho, USA, we surveyed for owls and woodpeckers to assess patterns of co-occurrence and evaluated the hypothesis that forest owls and woodpeckers co-occurred more frequently than expected by chance because of the facilitative nature of their biological interaction. We also examined co-occurrence patterns between owl species to understand their possible competitive interactions. Finally, to assess whether co-occurrence patterns arose because of species interactions or selection of similar habitat types, we used canonical correspondence analysis (CCA) to examine habitat associations within this cavity-nesting bird community. We found that Flammulated Owls co-occurred more with Hairy Woodpeckers (Picoides villosus), Northern Saw-whet Owls co-occurred with Northern Flickers (Colaptes auratus) and Red-naped Sapsuckers (Sphyrapicus nuchalis) and, when primary excavators were considered as a group, each species of owl was positively associated with the presence of woodpeckers. The owl species were distributed independently of one another suggesting a lack of competitive interactions. The CCA had relatively low explanatory power but suggested that habitat associations alone did not explain the patterns of positive co-occurrence we observed: Flammulated Owls and Hairy Woodpeckers associated with different habitats and Northern Saw-whet Owls, Northern Flickers, and Red-naped Sapsuckers appeared as habitat generalists. We interpret these patterns of co-occurrence and habitat use as evidence that woodpeckers facilitate presence of these species of owl and suggest management for forest owls could also include focus on the diurnal species with which they appear to associate.

Since 1945, over $4.9 trillion dollars of international aid has been allocated to developing countries. To date, there have been no estimates of the regional impact of this aid on the carbon cycle. We apply a geographically explicit matching method to estimate the relative impact of large-scale World Bank projects implemented between 2000 and 2010 on sequestered carbon, using a novel and publicly available data set of 61,243 World Bank project locations. Considering only carbon sequestered due to fluctuations in vegetative biomass caused by World Bank projects, we illustrate the relative impact of World Bank projects on carbon sequestration. We use this information to illustrate the geographic variation in the apparent effectiveness of environmental safeguards implemented by the World Bank. We argue that sub-national data can help to identify geographically heterogeneous impact effects, and highlight many remaining methodological challenges.

Spatially explicit models depicting species occupancy offer a useful conservation tool for land managers. Using occurrence data collected in 2009 and 2010 from the Boise National Forest, Idaho, we developed distribution models for Flammulated Owls (Psiloscops flammeolus) and Northern Saw-whet Owls (Aegolius acadicus) to explore associations between habitat factors and owl occupancy. We then spatially applied these models in a Geographic Information System. We considered land cover and topographic variables at three spatial scales: 0.4-km, 1-km, or 3-km-radius plots centered on point-count locations (n = 150) with resolution of land covers at 30 m. Flammulated Owls occupied 27 (18%) point-count locations and occurred in areas with a higher proportion of Douglas-fir (Pseudotsuga menziesii) at the 0.4-km scale, less diverse land cover composition at the 1-km scale, and in south-facing aspects at the 3-km scale. Northern Saw-whet Owls occupied 45 (30%) point-count locations and were associated with...

The Bureau of Land Management manages 246 million surface acres (100 million hectares) across the United States for multiple uses and sustained yield. Ensuring protection of ecological systems in the context of multiple, and often conflicting, resource uses and values is a challenge. Ecological integrity and land health are terms used by the Bureau of Land Management to describe the condition of ecological systems. Ecological integrity refers to the ability of ecological systems to support and maintain a community of organisms that is similar in composition, structure, and function to natural habitats within the region. We present a framework and process for assessing ecological integrity in terrestrial systems that accommodates the multiple-use mission of the Bureau of Land Management and is designed to inform future management actions. The nine steps in the assessment process are specifying the management question, identifying target resources and key stressors, defining spatial and temporal scales of analysis, selecting and evaluating indicators, defining the natural and acceptable range of variation for indicators, collecting and analyzing data, reporting results, using the results to inform and evaluate management actions, and repeating the assessment. We illustrate the process through a conceptual example outlining how the ecological integrity of rangelands across the western United States could be quantified. We propose a suite of six field-based indicators and six complementary broadscale indicators to provide multiscale information on the composition, structure, and function of rangelands. Data on 11 of the 12 proposed indicators are already being collected through the agency’s Assessment, Inventory, and Monitoring program. The framework and process presented here can help the BLM quantify ecological integrity to inform future planning and management actions in multiple-use landscapes.

Objective Cross-national studies provide inconclusive results as to the effectiveness of foreign health aid. We highlight a novel application of using subnational data to evaluate aid impacts, using Malawi as a case study. Design We employ two rounds of nationally representative household surveys (2004/2005 and 2010/2011) and geo-referenced foreign aid data. We examine the determinants of Malawi9s traditional authorities receiving aid according to health, environmental risk, socioeconomic and political factors. We use two approaches to estimate the impact of aid on reducing malaria prevalence and increasing healthcare quality: difference-in-difference models, which include traditional authority and month-of-interview fixed effects and control for individual and household level time-varying factors, and entropy balancing, where models balance on health-related and socioeconomic baseline characteristics. General health aid and four specific health aid sectors are examined. Results Traditional authorities with greater proportions of individuals living in urban areas, more health facilities and greater proportions of those in major ethnic groups were more likely to receive aid. Difference-in-difference models show health infrastructure and parasitic disease control aid reduced malaria prevalence by 1.20 (95% CI −0.36 to 2.76) and 2.20 (95% CI 0.43 to 3.96) percentage points, respectively, and increased the likelihood of individuals reporting healthcare as more than adequate by 12.1 (95% CI 1.51 to 22.68) and 14.0 (95% CI 0.11 to 28.11) percentage points. Entropy balancing shows similar results. Conclusions Aid was targeted to areas with greater existing health infrastructure rather than areas most in need, but still effectively reduced malaria prevalence and enhanced self-reported healthcare quality.

Within the United States (U.S.), state wildlife agencies are required to identify Species of Greatest Conservation Need (SGCN), the factors that impact these species, and the conservation actions needed to conserve these species through documentation of a Comprehensive Wildlife Conservation Strategy (CWCS). While the identification of SGCN represents an essential first step towards a comprehensive management strategy at the state level, the incorporation of this information into county level comprehensive plans will likely increase conservation efforts needed statewide. Our objective for this study was to use spatial data to delineate areas of human activity overlapping with areas rich in biodiversity to provide state wildlife agencies and local county planners recommended conservation actions to reduce biodiversity loss by human activities. Using the state of Idaho as an example, we delineated areas within the state where biodiversity hotspots for terrestrial and aquatic SGCN and human activities may be conflicting. We then identified counties within the state where these areas of conflict occur and identified conservation actions that may mitigate human activities to benefit SGCN. Our study used available geospatial data and a simple geographical information system (GIS) based approach which could be applied to other areas to support county-level land use planning for wildlife conservation.

Identification of biodiversity hotspots (hereafter, hotspots) has become a common strategy to delineate important areas for wildlife conservation. However, the use of hotspots has not often incorporated important habitat types, ecosystem services, anthropogenic activity, or consistency in identifying important conservation areas. The purpose of this study was to identify hotspots to improve avian conservation efforts for Species of Greatest Conservation Need (SGCN) in the state of Idaho, United States. We evaluated multiple approaches to define hotspots and used a unique approach based on weighting species by their distribution size and conservation status to identify hotspot areas. All hotspot approaches identified bodies of water (Bear Lake, Grays Lake, and American Falls Reservoir) as important hotspots for Idaho avian SGCN, but we found that the weighted approach produced more congruent hotspot areas when compared to other hotspot approaches. To incorporate anthropogenic activity into hotspot...

Conservation organizations are increasingly being held accountable for identifying and documenting measures of conservation success. We propose the use of human land-use spatial data to aid in the assessment of conservation efforts by monitoring qualitative change in the human footprint (i.e., spatial land-use measures of negative anthropogenic activity) within a hypothesis-driven framework to assess the effects of conservation efforts (i.e., positive anthropogenic activity). If human footprint data show that implemented conservation strategies mitigated or reduced negative anthropogenic influences, then a potential conservation approach is working. In contrast, if the implementation of conservation strategies did not mitigate or reduce the human footprint, then new conservation approaches may need to be developed or old ones refined. Human footprint data may offer great potential for assessing conservation efforts when used as part of a larger conservation monitoring strategy.

Landscapes available to birds to select for breeding locations are arrayed along multiple dimensions. Identifying the primary gradients structuring shrubsteppe bird communities in the western United States is important because widespread habitat loss and alteration are shifting the environmental template on which these birds depend. We integrated field habitat surveys, GIS coverages, and bird counts from 61 Breeding Bird Survey routes located in shrubsteppe habitats across a > 800 000 km 2 region to determine the gradients of habitat, topography, and geography underlying bird communities. A small set of habitat features dominated the primary environmental gradients in a canonical ordination; the 13 species in the shrubsteppe bird community were closely packed along the first two axes. Using hierarchical variance partitioning, we identified habitat as the most important pure (31% explained variation) or shared component. Topography (9%) and geography (4%) were minor components but each shared a larger contribution with habitat (habitat-topography 21%; habitat-geography 22%) in explaining the organization of the bird community. In a second tier partition of habitat structure, pure composition (% land cover) was more important (45%) than configuration (patch size and edge) (7%); the two components shared 27% of the explained variation in the bird community axes. Local (9%), community (14%), and landscape (10%) levels contributed equally. Adjacent organizational levels had a larger shared contribution (local-community 26%; community-landscape 27%) than more separated local-landscape levels (21%). Extensive conversion of shrubsteppe habitats to agriculture, exotic annual grasslands, or pinyon (Pinus spp.)-juniper (Juniperus spp.) woodlands is occurring along the primary axes of habitat structure. Because the shrubsteppe bird community was organized along short gradients dominated by habitat features, relatively small shifts in their available environment will exert a strong influence on these bird populations in the absence of buffering by alternative gradients.

There are no standards for assessment of the cumulative effects of underwater sound. Quantitative assessments typically consider a single source, whereas qualitative assessments may include multiple sources but rarely identify response variables. As a step toward understanding the cumulative effects of underwater sound, we assessed the aggregated sounds of multiple sources received by migrating bowhead whales (Balaena mysticetus). The quantitative method models the sound field from multiple sources and simulates movement of a population through it. The qualitative method uses experts to assess the responses of individuals and populations to sound sources and identify the potential mechanisms. These methods increase the transparency of assessments.

There are no standards for assessment of the cumulative effects of underwater sound. Quantitative assessments typically consider a single source, whereas qualitative assessments may include multiple sources but rarely identify response variables. As a step toward understanding the cumulative effects of underwater sound, we assessed the aggregated sounds of multiple sources received by migrating bowhead whales (Balaena mysticetus). The quantitative method models the sound field from multiple sources and simulates movement of a population through it. The qualitative method uses experts to assess the responses of individuals and populations to sound sources and identify the potential mechanisms. These methods increase the transparency of assessments.

Piñon (Pinus spp.) and juniper (Juniperus spp.) removal is a common management approach to restore sagebrush (Artemisia spp.) vegetation in areas experiencing woodland expansion. Because many management treatments are conducted to benefit sagebrush-obligate birds, we surveyed bird communities to assess treatment effectiveness in establishing sagebrush bird communities at study sites in Utah, Nevada, Idaho, and Oregon. Our analyses included data from 1 or 2 yr prior to prescribed fire or mechanical treatment and 3 to 5 yr posttreatment. We used detrended correspondence analysis to 1) identify primary patterns of bird communities surveyed from 2006 to 2011 at point transects, 2) estimate ecological scale of change needed to achieve treatment objectives from the relative dissimilarity of survey points to the ordination region delineating sagebrush bird communities, and 3) measure changes in pre- and posttreatment bird communities. Birds associated with sagebrush, woodlands, and ecotones were detected on our surveys; increased dissimilarity of survey points to the sagebrush bird community was characterized by a gradient of increased juniper and decreased sagebrush cover. Prescribed fires burned between 30% and 97% of our bird survey points. However, from 6% to 24% cover of piñon-juniper still remained posttreatment on the four treatment plots. We measured only slight changes in bird communities, which responded primarily to current vegetation rather than relative amount of change from pretreatment vegetation structure. Bird communities at survey points located at greater ecological scales from the sagebrush bird community changed least and will require more significant impact to achieve changes. Sagebrush bird communities were established at only two survey points, which were adjacent to a larger sagebrush landscape and following almost complete juniper removal by mechanical treatment. Our results indicate that management treatments that leave residual woodland cover and are not adjacent to extensive sagebrush stands are unlikely to establish sagebrush birds.

The decline of many species of Neotropical migrants has prompted increased research on their ecology on their breeding and wintering grounds. However, studies of their ecology during migration are relatively few. Despite documentation of molt-migration in at least six Neotropical passerine species, this phenomenon has been ignored in current conservation strategies for Neotropical migrants. In this review paper, we suggest that molt studies need to be done as a way to refine and improve conservation plans for Neotropical migrants. We identify three important questions that merit further study: (1) which Neotropical migrant species undergo flight feather molt at migratory-stopover sites; (2) where are molt-migration stopover sites geographically located; and (3) why are these sites preferred as stopover sites during molt? Finding answers to these questions will allow us to protect molt staging areas occupied by Neotropical migrants during migration as many wetland and nearshore oceanic habitats have been protected for molting waterfowl, shorebirds, and seabirds.

Independent of age or geographic variation, males of many species of birds exhibit dramatic variation in the expression of elaborate secondary sexual characters. "Good genes" models of sexual selection propose that males with relatively low resistance to parasites suffer high parasite loads that inhibit their ability to express these characters fully. In turn, variation in such characters may reliably indicate male quality and may be used by females to choose males. This is the first study to monitor (via mark-recapture) the long-term effects of parasites on color and growth of plumage in individual birds. Specifically, we used house finches, Carpodacus mexicanus, a sexually dimorphic species in which females are known to prefer more brightly plumaged males for mating, to test the hypothesis that high parasite load in males is correlated with poor physiological condition and reduced development of male secondary sex characters. Our results clearly demonstrate that both ectoparasitic feather mite (Proctoph...

The authors tested the effects of varying cage size on the behavior of 10 female and 10 male Macaca fascicularis by singly caging them for 2 weeks in each of 5 cage sizes, ranging from approximately 20% to 148% of regulation size. Behavior in the regulation cage size, a size 23% smaller, and a size 48% larger did not differ in any analysis. Locomotion was significantly less in the 2 smallest cage sizes. Abnormal behavior occurred only 5% of the time, did not increase as cage size decreased, and did not change significantly over nearly 3 years. Disruption of the normal activity budget in the laboratory environment proved to be a useful indicator of psychological well-being. Moving to a new room and, to a lesser extent, moving into a new, clean cage, regardless of size, was associated with disrupted sleep the 1st night and suppressed activity, especially self-grooming, the next day.