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Recent global declines of pollinator populations have highlighted the importance of pollinators, which are undervalued despite essential contributions to ecosystem services. To identify critical knowledge gaps about pollinators, we describe the state of knowledge about responses of pollinators and their foraging and nesting resources to historical natural disturbances and new stressors in Great Plains grasslands and riparian ecosystems. In addition, we also provide information about pollinator management and research needs to guide efforts to sustain pollinators and by extension, flowering vegetation, and other ecosystem services of grasslands. Although pollinator responses varied, pollinator specialists of disturbance-sensitive plants tended to decline in response to disturbance. Management with grazing and fire overall may benefit pollinators of grasslands, depending on many factors; however, we recommend habitat and population monitoring to assess outcomes of these disturbances on small, isolated pollinator populations. The influences and interactions of drought and increasingly variable weather patterns, pesticides, and domesticated bees on pollinators are complex and understudied. Nonetheless, habitat management and restoration can reduce effects of stressors and augment floral and nesting resources for pollinators. Research needs include expanding information about 1) the distribution, abundance, trends, and intraregional variability of most pollinator species; 2) floral and nesting resources critical to support pollinators; 3) implications of different rangeland management approaches; 4) effects of missing and reestablished resources in altered and restored vegetation; and 5) disentangling the relative influence of interacting disturbances and stressors on pollinator declines. Despite limited research in the Great Plains on many of these topics, consideration of pollinator populations and their habitat needs in management plans is critical now to reduce future pollinator declines and promote recovery.

DNA metabarcoding of pollen is a useful tool for studying bee foraging ecology. However, several questions about this method remain unresolved, including the extent to which sequence read data is quantitative, which type of sequence count removal threshold to use and how that choice affects our ability to detect rare flower visits, and how sequence artefacts may confound conclusions about bee foraging behavior. To address these questions, we isolated pollen from five plant species and created treatments comprised of pollen from each species alone and combinations of pollen from multiple species that varied in richness and evenness. We used ITS2 and rbcL metabarcoding to identify plant species in the samples, compared the proportion of pollen by mass to the proportion of sequencing reads for each plant species in each treatment, and analyzed the sequencing data using both liberal and conservative thresholds. We collected pollen from foraging bees, analyzed metabarcoding data from those samples using each threshold, and compared the differences in the pollinator networks constructed from the data. Regardless of the threshold used, the relationship between the proportion of pollen by mass and sequencing reads was inconsistent, suggesting that the number of sequence reads is a poor proxy for pollen abundance in mixed-species samples. Using a liberal threshold resulted in greater detection of original plant species in mixtures but also detected additional species in mixtures and single-species samples. The conservative threshold reduced the number of additional plant species detected, but several species in mixtures were not detected above the threshold, resulting in false negatives. Pollinator networks produced using the two thresholds differed and illustrated tradeoffs between detection of rare species and estimation of network complexity. Threshold selection can have a major effect on conclusions drawn from studies using metabarcoding of bee pollen to study plant-pollinator interactions.

The behavioral mechanisms by which predators encounter prey are poorly resolved. In particular, the extent to which predators engage in active search for prey versus incidentally encountering them is unknown. The distinction between search and incidental encounter influences prey population dynamics with active search exerting a stabilizing force on prey populations by alleviating predation pressure on low-density prey and increasing it for high-density prey.Parturition of many large herbivores occurs during a short and predictable temporal window in which young are highly vulnerable to predation. Our study aims to determine how a suite of carnivores responds to the seasonal pulse of newborn ungulates using contemporaneous GPS locations of four species of predators and two species of prey.We used step-selection functions to assess whether coyotes, cougars, black bears, and bobcats actively searched for parturient females in a low-density population of mule deer and a high-density population of elk. We then assessed whether searching carnivores shifted their habitat use toward areas exhibiting a high probability of encountering neonates.None of the four carnivore species encountered parturient mule deer more often than expected by chance suggesting that predation of young resulted from incidental encounters. By contrast, we determined that cougar and male bear movements positioned them in proximity of parturient elk more often than expected by chance which is evidence of searching behavior. Although both male bears and cougars searched for neonates, only male bears used elk parturition habitat in a way that dynamically tracked the phenology of the elk birth pulse suggesting that maximizing encounters with juvenile elk was a motivation when selecting resources.Our results support the existence of a stabilizing mechanism to prey populations through active search behavior by predators because carnivores in our study searched for the high-density prey species (elk) but ignored the low-density species (mule deer). We conclude that prey density must be high enough to warrant active search, and that there is high interspecific and intersexual variability in foraging strategies among large mammalian predators and their prey.

Mesopredator release theory suggests that dominant predators suppress subordinate carnivores and ultimately shape community dynamics, but the assumption that subordinate species are only negatively affected ignores the possibility of facilitation through scavenging. We examined the interplay within a carnivore community consisting of cougars, coyotes, black bears, and bobcats using contemporaneous Global Positioning System telemetry data from 51 individuals; diet analysis from 972 DNA-metabarcoded scats; and data from 128 physical investigations of cougar kill sites, 28 of which were monitored with remote cameras. Resource provisioning from competitively dominant cougars to coyotes through scavenging was so prolific as to be an overwhelming determinant of coyote behavior, space use, and resource acquisition. This was evident via the strong attraction of coyotes to cougar kill sites, frequent scavenging of cougar-killed prey, and coyote diets that nearly matched cougars in the magnitude of ungulate consumption. Yet coyotes were often killed by cougars and used space to minimize encounters, complicating the fitness benefits gained from scavenging. We estimated that 23% (95% CI: 8 to 55%) of the coyote population in our study area was killed by cougars annually, suggesting that coyote interactions with cougars are a complex behavioral game of risk and reward. In contrast, we found no indication that bobcat space use or diet was influenced by cougars. Black bears avoided cougars, but there was no evidence of attraction to cougar kill sites and much lower levels of ungulate consumption and carcass visitation than for coyotes. Interspecific interactions among carnivores are multifaceted, encompassing both suppression and facilitation.

Spatial capture-recapture (SCR) models have become the preferred tool for estimating densities of carnivores. Within this family of models are variants requiring identification of all individuals in each encounter (SCR), a subset of individuals only (generalized spatial mark-resight, gSMR), or no individual identification (spatial count or spatial presence-absence). Although each technique has been shown through simulation to yield unbiased results, the consistency and relative precision of estimates across methods in real-world settings are seldom considered. We tested a suite of models ranging from those only requiring detections of unmarked individuals to others that integrate remote camera, physical capture, genetic, and global positioning system (GPS) data into a ‘hybrid’ model, to estimate population densities of black bears, bobcats, cougars, and coyotes. For each species we genotyped fecal DNA collected with detection dogs during a 20-day period. A subset of individuals from each species was affixed with GPS collars bearing unique markings and resighted by remote cameras over 140 days contemporaneous with scat collection. Camera-based gSMR models produced density estimates that differed by less than 10% from genetic SCR for bears, cougars, and coyotes once important sources of variation (sex or behavioral status) were controlled for. For bobcats, SCR estimates were 33% higher than gSMR. The cause of the discrepancies in estimates was likely attributable to challenges designing a study compatible for species with disparate home range sizes and the difficulty of collecting sufficient data in a timeframe in which demographic closure could be assumed. Unmarked models estimated densities that varied greatly from SCR, but estimates became more consistent in models wherein more individuals were identifiable. Hybrid models containing all data sources exhibited the most precise estimates for all species. For studies in which only sparse data can be obtained and the strictest model assumptions are unlikely to be met, we suggest researchers use caution making inference from models lacking individual identity. For best results, we further recommend the use of methods requiring at least a subset of the population is marked and that multiple datasets are incorporated when possible.

Consistent with a warming climate, the timing of key phenological phases (i.e. phenophases) for many plant species is shifting, but the direction and extent of these shifts remain unclear. For large herbivores such as ungulates, altered plant phenology can have important nutritional and demographic consequences. We used two multi-year datasets collected during 1992–1996 and 2015–2019 of understory plant phenology in semi-arid forested rangelands in northeastern Oregon, United States, to test whether the duration of phenophases for forage species has changed over time for three plant functional groups (forbs, graminoids, and shrubs). Duration of spring green-up was approximately 2 weeks shorter in the later years for forbs (19 ± 3.8 d) and graminoids (13.2 ± 2.8 d), and senescence was 3 weeks longer for graminoids (25.1 ± 5.1) and shrubs (22.0 ± 4.6). Average peak flowering date was 3.1 ± 0.2 d earlier per decade for understory forage species with approximately 1/3 of the species (35%) exhibiting earlier peak flowering dates over time. Variation in late-winter precipitation had the greatest effect on the duration of understory green-up, whereas variation in summer precipitation had a greater effect on duration of the senescent period. Collectively, these results indicate climate-related progression towards shorter periods of peak plant productivity, and earlier and longer periods of plant senescence, the combination of which substantially reduces the temporal window of forage available in growing forms most usable to herbivores. This work adds a needed component to the climate change literature, by describing links between shifting climate variables, multiple phases of understory plant phenology, and possible nutritional consequences for herbivores under a warming climate.

Many pollinator populations are experiencing declines, emphasizing the need for a better understanding of the complex relationship between bees and flowering plants. Using DNA metabarcoding to describe plant-pollinator interactions eliminates many challenges associated with traditional methods and has the potential to reveal a more comprehensive understanding of foraging behaviour and pollinator life history. Here we use DNA metabarcoding of ITS2 and rbcL gene regions to identify plant species present in pollen loads of 404 bees from three habitats in eastern Oregon. Our specific objectives were to (i) determine whether plant species identified using DNA metabarcoding are consistent with plant species identified using observations, (ii) compare characterizations of diet breadth derived from foraging observations to those based on plant species assignments obtained using DNA metabarcoding, and (iii) compare plant species assignments produced by DNA metabarcoding using a "regional" reference database to those produced using a "local" database. At the three locations, 31%-86% of foraging observations were consistent with DNA metabarcoding data, 8%-50% of diet breadth characterizations based on observations differed from those based on DNA metabarcoding data, and 22%-25% of plant species detected using the regional database were not known to occur in the study area in question. Plant-pollinator networks produced from DNA metabarcoding data had higher sampling completeness and significantly lower specialization than networks based on observations. Here, we examine some strengths and limitations of using DNA metabarcoding to identify plant species present in bee pollen loads, make ecological inferences about foraging behaviour and provide guidance for future research.

Mesopredator release theory suggests that dominant predators suppress subordinate carnivores and ultimately shape community dynamics, but the assumption that subordinate species are only negatively affected ignores the possibility of facilitation through scavenging. We examined the interplay within a carnivore community consisting of cougars, coyotes, black bears, and bobcats using contemporaneous Global Positioning System telemetry data from 51 individuals, diet analysis from 972 DNA-metabarcoded scats, and data from 128 physical investigations of cougar kill sites, 28 of which were monitored with remote cameras. Resource provisioning from competitively-dominant cougars to coyotes through scavenging was so prolific as to be an overwhelming determinant of coyote behavior, space use, and resource acquisition. This was evident via strong attraction of coyotes to cougar kill sites, frequent scavenging of cougar-killed prey, and coyote diets that nearly matched cougars in the magnitude of ungulate consumption. Yet coyotes were often killed by cougars and used space to minimize encounters, complicating the fitness benefits gained from scavenging. We estimated that 23% (95% CI: 8–55%) of the coyote population in our study area was killed by cougars annually suggesting that coyote interactions with cougars are a complex behavioral game of risk and reward. In contrast, we found no indication that bobcat space use or diet was influenced by cougars. Black bears avoided cougars, but there was no evidence of attraction to cougar kill sites, and much lower levels of ungulate consumption and carcass visitation than for coyotes. Interspecific interactions among carnivores are multifaceted encompassing both suppression and facilitation.Significance StatementAn incomplete understanding of the total influence competitively-dominant predators exert on subordinate species hinders our ability to anticipate the effects that changing carnivore populations will have in ecological communities. Here we show that cougars are the architects of a complex behavioral game of risk and reward, as subordinate or co-occurring carnivores are both provisioned and preyed on by the dominant predators. Each co-occurring carnivore species considered here employed a different strategy to approach the risk-reward tradeoff suggesting there are multiple viable solutions to the game. By not considering the multitude of effects dominant predators have on other carnivores, we are missing important linkages in terrestrial food webs.

Variation among demographic rates for a population reflects the allocation of available energy by individuals to competing life-history strategies. Species exhibiting slow-paced life histories often prioritize energy allocation to adult survival over any single reproductive event, therefore maximizing future reproductive potential. Survival of adult female ungulates is generally high with little variability, whereas survival of young is lower and often highly variable. When adult survival is high with low variability, juvenile survival may have a proportionally greater effect on population growth or decline. Weather also may affect population dynamics directly by influencing survival of young or adults, or indirectly through changes in nutritional condition of adult females that influence population growth rates. We experimentally manipulated forage availability during winter, by supplementing native forage with high-energy pelleted feed ad libitum, to a subset of a population of mule deer (Odocoileus hemionus) to understand the effects of winter nutrition on survival of adult females and their young born the subsequent summer. We evaluated the effects of winter nutrition, individual-based parameters, and environmental covariates on survival of adult female mule deer from 2013 to 2018, and neonatal mule deer from 2014 to 2016. We documented a 26% decrease in annual survival of adult female mule deer in 2017 in response to increased snowpack during the preceding winter. Neonates born to females that receive enhanced nutrition during winter preceding parturition had higher survival to weaning (0.49, SE = 0.12), compared to neonates born to females that did not receive enhanced nutrition (0.29, SE = 0.07).We observed no effect of enhanced winter nutrition on survival of adult females. Our results suggested winter nutrition of maternal females may influence juvenile survival and demonstrates the importance of forage quality available to adult females during mid-pregnancy. Although we were unable to detect an effect of winter forage on survival of adults, direct effects of deep winter snow resulted in lower survival of adult females. Low survival of adult females in our study population is indicative of a declining population.

The degradation of dry woodlands in South America by agricultural activities affects wildlife through a decrease in available habitat and fine-scale changes in habitat structure. The impact of land use can be perceived by small, mobile organisms as preventing or facilitating their movement through and among habitats, consequently altering ecosystem functions. By tracking with radiotelemetry we describe for the first time the pattern of movement of a small mammal (Graomys griseoflavus) that inhabits dry woodland ecosystems in South America and its relationship with environmental features that affect movement. We measured environmental variables linked to the ecological requirements of the species (e.g., plant cover and patches of forage species consumed) in restored and grazed woodlands and compared movements between seasons (dry and wet). We found that the fine-scale differences in the vegetation cover associated with livestock grazing changed the mobility and use of space of this small mammal. The step-lengths and used area for G. griseoflavus were greater under passive restoration compared to the area grazed by livestock. Small rodents moved between patches of similar mean size of forage species, avoiding large inter-patches of bare ground. Although both management conditions showed seasonal variations in plant cover, the step-lengths decreased significantly in the grazed woodland during the wet season, while step-lengths in the restored area were unaffected by season. The fine-scale spatial arrangement of plants in restored woodlands elucidated notable changes in animal movement on grazed lands, suggesting that space use by small mammals may be an important tool to identify habitat structures that facilitate the movement of animals in restoration of degraded systems. Fil: Spirito, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina Fil: Rowland, Mary. Forestry And Range Sciences Laboratory; Estados Unidos Fil: Wisdom, Michael. Forestry And Range Sciences Laboratory; Estados Unidos Fil: Tabeni, Maria Solana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina

Trail-based recreation is a popular use of public forests in the United States, and four types are common: all-terrain vehicle (ATV) riding, mountain biking, hiking, and horseback riding. Effects on wildlife, however, are controversial and often a topic of land use debates. Accordingly, we studied trail-based recreation effects on elk (Cervus canadensis), a wide-ranging North American ungulate highly sought for hunting and viewing on public forests, but that is sensitive to human activities, particularly to motorized traffic on forest roads. We hypothesized that elk would respond to trail-based recreation similarly to their avoidance of roads open to motorized traffic on public forests. We evaluated elk responses using a manipulative landscape experiment in a 1453-ha enclosure on public forest in northeast Oregon. A given type of recreation was randomly selected and implemented twice daily along 32 km of designated recreation trails over a five-day period, followed by a nine-day control period of no human activity. Paired treatment and control replicates were repeated three times per year for each recreation type during spring-fall, 2003–2004. During treatments, locations of elk and recreationists were simultaneously collected with telemetry units. Elk locations also were collected during control periods. Elk avoided the trails during recreation treatments, shifting distribution farther out of view and to areas farthest from trails. Elk shifted distribution back toward trails during control periods of no human activity. Elk avoided recreationists in real time, with mean minimum separation distances from humans that varied from 558 to 879 m among the four treatments, 2–4 times farther than elk distances from trails during recreation. Separation distances maintained by elk from recreationists also were 3–5 times farther than mean distances at which elk could be viewed from trails. Distances between elk and recreationists were highest during ATV riding, lowest and similar during hiking and horseback riding, and intermediate during mountain biking. Our results support the hypothesis that elk avoid trail-based recreation similarly to their avoidance of roads open to motorized traffic on public forests. Forest managers can use results to help optimize trade-offs between competing objectives for trail-based recreation and wildlife species like elk that are sensitive to human activities on public forests.

Las tierras secas ocupan casi el 50% de la superficie de la tierra y están sujetas a un creciente avance de usos extensivos como el pastoreo por ganado. Estas prácticas afectan múltiples interacciones bióticas y abióticas y la disponibilidad de recursos para especies nativas. En este trabajo se examinaron los efectos de los cambios generados por el pastoreo en estructura del hábitat a escala local sobre la selección y disponibilidad de recursos por parte de un pequeño mamífero nativo. El estudio se realizó en un ecosistema de bosque seco sujeto a diferentes manejos (un área con restauración pasiva, Reserva del Hombre y la Biosfera de Ñacuñán; y un área con pastoreo vacuno continuo). Mediante la técnica de radio-telemetría se realizó el seguimiento de individuos de Graomys griseoflavus, y se calcularon las funciones de selección de recursos para evaluar uso del hábitat. Los modelos de selección de recursos se crearon a partir del uso de variables de hábitat medidas en ambas áreas. Se planteó la hipótesis que los cambios de largo plazo en la vegetación debido al pastoreo vacuno influenciaron el uso del hábitat del pequeño mamífero. G. griseoflavus seleccionó parches de vegetación que contienen una alta cobertura de especies presentes en su dieta, alta riqueza de especies y una gran cobertura de hierbas y árboles, evitando los espacios inter-parches. Si bien los patrones de selección de recursos fueron similares en ambas condiciones de manejo (es decir, bajo restauración pasiva y pastoreo), la fuerza de la selección fue mayor en el área pastoreada. El modelo final de selección de recursos fue validado a través del método de validación cruzada, obteniendo un alto ajuste para el mismo (R2 = 0.61). Debido a la importancia funcional de los pequeños mamíferos en ecosistemas áridos, la gestión dirigida a preservar sus requerimientos ecológicos de hábitat constituye una herramienta importante para la conservación y recuperación de zonas áridas degradadas. Drylands occupy almost 50% of the Earth's surface and are increasingly affected by extensive land uses such as grazing. These practices affect multiple biotic and abiotic interactions mainly through loss of habitat and resources available for native wildlife. We examined the effects of local vegetation conditions on resource selection by a small mammal species in drylands with different resource availability. The study was conducted in a semi-arid woodland that included an area protected from livestock grazing and human settlement for more than 50 years, the Man and the Biosphere Ñacunán Reserve, and an adjoining area that has experienced long-term cattle grazing. We tracked radio-collared individuals of Graomys griseoflavus, the most abundant small mammal in the Ñacunán region, and calculated resource selection functions (RSFs) to evaluate habitat selection. We modeled resource selection using a suite of habitat variables measured in both areas. We hypothesized that long-term changes in vegetation associated with livestock grazing would substantially influence habitat selection. G. griseoflavus selected vegetation patches with relatively greater cover of forage species (i.e., taxa commonly consumed) and avoided open spaces; they also selected sites with greater species richness and cover of grasses and trees. Although resource selection patterns were generally similar under both management conditions (i.e., under passive restoration and grazing), the strength of selection was greater in the grazed area. The final RSF model validated well with k-fold cross-validation (R2 = 0.61). Because of the importance of rodents in ecosystem function, management to meet their resource requirements could be an important tool for habitat restoration in degraded drylands. Fil: Spirito, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina Fil: Rowland, Mary. United States Forest Service; Estados Unidos Fil: Nielson, Ryan. Western Ecosystems Technology; Estados Unidos Fil: Wisdom, Michael. United States Forest Service; Estados Unidos Fil: Tabeni, Maria Solana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina

These data and analyses support the research article “Wild ungulate herbivory suppresses deciduous woody plant establishment following salmonid stream restoration” Averett et al. (2017) [1] . The data and analyses presented here include: (1) planting density, survival and growth (two years post restoration) of riparian plantings along an ~11 km stream reach in northeastern Oregon as a function of herbivory treatment (protected/not protected from wild ungulate herbivory), habitat type, and planting species; and (2) abundance and height distributions of naturally occurring deciduous woody species along the restored stream reach two years post restoration. Survival and growth analyses are provided as output from multiple logistic and mixed effect regression models respectively.

Domestic and wild ungulates can exert strong influences on riparian woody vegetation establishment, yet little is known about how wild ungulate herbivory affects riparian restoration in the absence of cattle. We evaluated elk (Cervus elaphus) and mule deer (Odocoileus hemionus) impacts on the establishment of deciduous woody riparian plantings along 11 km of Meadow Creek, a steelhead (Oncorhynchus mykiss) and Chinook (Oncorhynchus tshawytscha) salmon stream in northeastern Oregon, USA. We compared survival and growth between protected and unprotected plantings (from wild ungulates), and assessed the contribution of the plantings to the total deciduous woody cover after two growing seasons. Riparian use by wild ungulates was estimated by tracking a subset of the deer and elk populations using global positioning system telemetry collars. Elk riparian use was 11 times greater than deer, and in contrast to elk, deer were functionally absent from greater than 50% of the restored reach. Wild ungulate herbivory decreased planting survival by 30%, and growth by 73%, and was most detrimental to cottonwood (Populus balsamifera; increased likelihood of mortality by 5 times and suppressed growth by more than 90%). Herbivory impacts resulted in survival rates below regional criteria (50%) for restoration success after only two growing seasons. Naturally recovering shrubs accounted for 99% of the deciduous woody cover, and were mostly composed of the same species or genera as those planted. Our results suggest that wild ungulate herbivory can impede riparian restoration along salmonid streams by suppressing woody plant establishment and recovery.

The life‐and‐death stakes of predator–prey encounters justify the high price of many anti‐predator behaviors. In adopting these behaviors, prey incur substantial non‐consumptive costs that can have population‐level consequences. Because prey knowledge of risk is imperfect, individuals may even adopt these costly behaviors in the absence of a real threat. For example, rather than only avoid hunters, many species categorically avoid all anthropogenic activity. Although hunting seasons only increase risk for specific individuals (e.g., males), non‐target individuals may still perceive human hunters as a source of risk and respond accordingly. Here, we used a large‐scale experiment including 89 animal‐years of location data from 62 unique individuals over 6 yr to quantify the duration, magnitude, and energetic consequences of changes to movement and resource selection behavior adopted by non‐target female elk (Cervus canadensis) in response to human hunters during three separate experimental 5‐d hunts (elk archery, deer rifle (Odocoileus hemionus or Odocoileus virginianus), and elk rifle). We predicted that elk response to hunters would be brief, but that strong behavioral responses to hunters (e.g., strengthened avoidance of roads and trails) would carry nutritional costs. We measured the duration of hunt‐related changes in elk speed using quantile regression, further quantified the strength of elk behavioral responses to hunters using population‐level resource selection functions, and evaluated whether anti‐predator resource selection behavior translated to measurable metabolic costs in the form of reduced body fat heading into winter. Elk responses to human hunters were stronger in the day than at night and were generally more pronounced during the elk hunts than during deer hunts. During hunts, elk shifted their diurnal behavior to avoid forage and intensified their avoidance of roads and trails. The combination of these changes in behavior led to a predicted pattern of distribution during the hunt that differed substantially from the distribution prior to the hunt. Lactating females that more strongly avoided roads entered winter in poorer nutritional condition, suggesting that the changes in resource selection we describe carry corresponding nutritional costs that have the potential to impact subsequent population performance.

Many federal, state, and tribal agencies, as well as nonprofit organizations, have recently increased efforts to understand how natural areas can be managed to enhance native pollinators and the ecosystem services they provide. However, managing this important group must be balanced with other services that natural areas provide including hunting, timber production, and livestock grazing. Significant knowledge gaps exist about how to effectively manage habitats used by large ungulates (e.g., cattle (Bos taurus), elk (Cervus elaphus), mule deer (Odocoileus hemionus)) in ways that also enhance pollinators. One key gap is understanding the degree to which diets of mammalian herbivores overlap with floral resources used by bees, and how this overlap varies spatially and temporally. Invertebrate pollinators, including bees, rely on flowering forbs and shrubs for nectar and pollen. Ungulates also feed on flowering plants, although preferences vary by ungulate species, vegetation community, and season....

Climate change models are predicting increased frequency and severity of droughts in arid and semiarid environments, and these areas are responsible for much of the world’s livestock production. Because cattle (Bos Taurus) grazing can impact the abundance, distribution, and ecological function of native plant and animal communities, it is important to understand how cattle might respond to increasingly arid conditions. Here, we evaluate changes in habitat selection by cattle across an 8-yr period as a function of rainfall and other environmental covariates. Using resource selection functions, we evaluated habitat selection based on 2 behaviors, stationary and mobile. Models revealed similarity in cattle habitat selection across years, with only modest changes in selection as a function of precipitation, despite marked seasonal and interannual differences in rainfall. Cattle preferred gentle slopes, forest edges, wet meadows, and areas near water as well as areas far from water on plateaus. Cattle avoided areas at intermediate distances from water, typically associated with steep slopes. As conditions became drier during the late season, cattle did not switch selection patterns but instead contracted their selection around water. Cattle also selected similar habitats whether they were mobile or stationary, possibly making microsite decisions therein. This consistent pattern of selection across years could be particularly problematic for riparian communities as climates become drier; however, it may also simplify cattle management, as range managers can focus vegetation monitoring efforts on riparian areas. Due to the uncertainty surrounding future climatic conditions, it is imperative that both range and wildlife managers develop longterm plans to continue managing these multiuse landscapes in an ecologically sustainable manner based on expected patterns of livestock grazing.

Mountain pine beetle (Dendroctonus ponderosae) (MPB) outbreaks are increasingly prevalent in western North America, causing considerable ecological change in pine (Pinus spp.) forests with important implications for wildlife. We reviewed studies examining wildlife responses to MPB outbreaks and postoutbreak salvage logging to inform forest management and guide future research. Our review included 16 studies describing MPB outbreak relationships with 89 bird species and 6 studies describing relationships with 11 mammalian species, but no studies of reptiles or amphibians. We included studies that compared wildlife response metrics temporally (before versus after the outbreak) and spatially (across sites that varied in severity of outbreak) in relation to beetle outbreaks. Outbreaks ranged in size from 20,600 to 107 ha and studies occurred 1-30 years after the peak MPB outbreak, but most studies were conducted over the short-term (i.e., 6 years after the peak of MPB-induced tree mortality). Birds were the only taxa studied frequently; however, high variability existed among those studies to allow many inferences, although some patterns were evident. Avian studies concluded that cavity-nesting species responded more favorably to beetle-killed forests than species with open-cup nests, and species nesting in the shrub layer favored outbreak forests compared with ground and open-cup canopy nesters that generally showed mixed relationships. Bark-drilling species as a group clearly demonstrated a positive short-term association with MPB epidemics compared with that of other foraging assemblages. Cavity-nesting birds that do not consume bark beetles (i.e., secondary cavity-nesting species and nonbark-drilling woodpeckers) also exhibited some positive responses to MPB outbreaks, although not as pronounced or consistent as those of bark-drilling woodpeckers. Mammalian responses to MPB outbreaks were mixed. Studies consistently reported negative effects of MPB outbreaks on red squirrels (Tamiasciurus hudsonicus). However, there is evidence that red squirrels can persist after an outbreak under some conditions, e.g., when nonhost tree species are present. For small mammal species associated with forest understories, responses may be most pronounced during the postepidemic period ( 6 years after the peak of beetle-induced tree mortality) when snags fall to produce coarse woody debris. Postoutbreak salvage logging studies (n = 6) reported results that lacked consensus. Postoutbreak salvage logging may have an impact on fewer wildlife species than postfire salvage logging, probably because only host-specific tree species are removed after beetle outbreaks.

Native bees are declining worldwide, but conserving or restoring their habitat requires a better understanding of bee-flower associations. High quality bee habitat includes flowers that provide pollen and nectar preferred by bees. However, little data exist about which plants are commonly used by bees in the Pacific Northwest, or whether bees prefer certain plant characteristics over others. We examined bee and plant communities in an Oregon riparian ecosystem. Our purpose was to describe bee-plant associations, determine which plants are most frequently visited by bees, identify plants that may be preferred by bees, and examine how a plant's native status, flower color, and floral morphology affect the types of bees visiting it. We found that many blooming plants received a diverse set of bee visitors, but some plants had a higher number and species richness of visiting bees than others. No plant species seemed limited to visitation by a small set of specialist bees. The number and type of visit...

Sagebrush ecosystems are among the largest and most threatened ecosystems in North America. Greater sage-grouse has served as the bellwether for species conservation in these ecosystems and has been considered for listing under the Endangered Species Act eight times. In September 2015, the decision was made not to list greater sage-grouse, but to reevaluate its status in 5 years. Concerns over sage-grouse and associated habitats have set in motion sweeping Federal and State land management plan changes and proactive science-based conservation actions to address threats within the realm of management control. For nearly a century, the Forest Service (FS), U.S. Department of Agriculture (USDA), has studied sagebrush ecosystems and for decades has focused on sage-grouse biology and habitat requirements. Our team of FS scientists and managers prepared this assessment to summarize FS strengths, capabilities, partners, past and current research, and potential future high-priority research areas for conservation and restoration of sagebrush ecosystems and sage-grouse. We identified research and science-based management needs of the National Forest System where lands are important for breeding and brood-rearing habitats for sage-grouse. We recommend expanded research and science delivery by FS scientists. This work will help meet continuing widespread concerns and calls for science-based conservation to mitigate threats to sagebrush ecosystems, conserve populations of sage-grouse and other sagebrush-obligate species, and restore sagebrush ecosystems throughout the western United States.

Widespread degradation of the sagebrush ecosystem in the western United States, including the invasion of cheatgrass, has prompted resource managers to consider a variety of approaches to restore and conserve habitats for sagebrush-associated species. One such approach involves the use of greater sage-grouse, a species of prominent conservation interest, as an umbrella species. This shortcut approach assumes that managing habitats to conserve sage-grouse will simultaneously benefit other species of conservation concern. The efficacy of using sage-grouse as an umbrella species for conservation management, however, has not been fully evaluated. We tested that concept by comparing: (1) commonality in land-cover associations, and (2) spatial overlap in habitats between sage-grouse and 39 other sagebrush-associated vertebrate species of conservation concern in the Great Basin ecoregion. Overlap in species land-cover associations with those of sage-grouse, based on the u (phi) correlation coefficient, was substantially greater for sagebrush obligates ð� ¼ 0:40Þ than non-obligates ð� ¼ 0:21Þ. Spatial overlap between habitats of target species and those associated with sage-grouse was low (mean u = 0.23), but somewhat greater for habitats at high risk of displacement by cheatgrass (mean u = 0.33). Based on our criteria, management of sage-grouse habitats likely would offer relatively high conservation coverage for sagebrush obligates such as pygmy rabbit (mean u = 0.84), but far less for other species we addressed, such as lark sparrow (mean u = 0.09), largely due to lack of commonality in land-cover affinity and geographic ranges of these species and sage-grouse.

The wolverine (Gulo gulo) is an uncommon, wide-ranging carnivore of conservation concern. We evaluated performance of landscape models for wolverines within their historical range at 2 scales in the interior Northwest based on recent observations (n = 421) from Washington, Oregon, Idaho, and Montana. At the subbasin scale, simple overlays of habitat and road-density classes were effective in predicting observations of wolverines. At the watershed scale, we used a Bayesian belief network model to provide spatially explicit estimates of relative habitat capability. The model has 3 inputs: amount of habitat, human population density, and road density. At both scales, the best models revealed strong correspondence between means of predicted counts of wolverines and means of observed counts (P < 0.001). Our results can be used to guide regional conservation planning for this elusive animal.

Valid modeling of habitats and populations of Greater Sage-Grouse ( Centrocercus urophasianus) is a critical management need because of increasing concern about population viability. Consequently, we evaluated the performance of two models designed to assess landscape conditions for Greater Sage-Grouse across 13.6 million ha of sagebrush steppe in the interior Columbia Basin and adjacent portions of the Great Basin of the western United States (referred to as the basin). The first model, the environmental index model, predicted conditions at the scale of the subwatershed (mean size of approximately 7800 ha) based on inputs of habitat density, habitat quality, and effects of human disturbance. Predictions ranged on a continuous scale from 0 for lowest environmental index to 2 for optimal environmental index. The second model, the population outcome model, predicted the composite, range-wide conditions for sage grouse based on the contribution of environmental index values from all subwatersheds and measures of range extent and connectivity. Population outcomes were expressed as five classes (A through E) that represented a gradient from continuous, well-distributed populations (outcome A) to sparse, highly isolated populations with a high likelihood of extirpation (outcome E). To evaluate performance, we predicted environmental index values and population outcome classes in areas currently occupied by sage grouse versus areas where extirpation has occurred. Our a priori expectations were that models should predict substantially worse environmental conditions ( lower environmental index) and a substantially higher probability of extirpation ( lower population outcome class) in extirpated areas. Results for both models met these expectations. For example, a population outcome of class E was predicted for extirpated areas, as opposed to class C for occupied areas. These results suggest that our models provided reliable landscape predictions for the conditions tested. This finding is important for conservation planning in the basin, where the models were used to evaluate management of federal lands for sage grouse. Resumen: Modelos validos de habitat y de poblaciones del urogallo (Centrocercus urophasianus) son una necesidad critica para su manejo debido a la creciente preocupacion por la viabilidad de la poblacion. Por lo tanto, evaluamos el funcionamiento de dos modelos disenados para evaluar las condiciones del paisaje para el urogallo en 13.6 millones de ha de la estepa de artemisa en la Cuenca Columbia Interior y las porciones adyacentes de la Gran Cuenca de los Estados Unidos occidentales (referidos como cuenca). El primer modelo (modelo de indice ambiental) predijo condiciones a escala de la subcuenca (tamano promedio ≈ 7800 ha) basado en informacion de la densidad del habitat, calidad del habitat y efectos de la perturbacion humana. Las predicciones variaron en una escala continua a partir de 0 (el indice ambiental mas bajo) a 2 (indice ambiental optimo). El segundo modelo (modelo del resultado de la poblacion) predijo las condiciones compuestas, de amplio rango, para el urogallo con base en la contribucion de los valores de indice ambiental de todas las subcuencas y las medidas de extension y de conectividad de la pradera. Los resultados de la poblacion fueron expresados en cinco clases (A - E) que representan un gradiente de poblaciones continuas, bien-distribuidas (resultado A) a poblaciones escasas, altamente aisladas con una alta probabilidad de extirpacion (resultado E). Para evaluar el funcionamiento, predijimos valores de indice ambiental y resultados de la poblacion en las areas actualmente ocupadas por urogallos versus areas donde ha ocurrido la extirpacion. Nuestras expectativas a priori eran que los modelos deben predecir condiciones ambientales substancialmente peores (indice ambiental mas bajo) y una probabilidad de extirpacion sustancialmente mayor (menor resultado de la poblacion) en areas extirpadas. Los resultados para ambos modelos cumplieron estas expectativas. Por ejemplo, se predijo un resultado de la poblacion de la clase E para areas extirpadas, en comparacion con la clase C para areas ocupadas. Estos resultados sugieren que nuestros modelos proporcionaron predicciones de paisaje confiables para las condiciones probadas. Este hallazgo es importante para planeacion de la conservacion de la cuenca, donde los modelos fueron utilizados para evaluar el manejo de terrenos federales para urogallos.

Habitats of Greater Sage-Grouse (Centrocercus urophasianus) have declined across western North America, and most remaining habitats occur on lands administered by the U.S. Forest Service ( FS) and U.S. Bureau of Land Management ( BLM). Consequently, managers of FS–BLM lands need effective strategies to recover sagebrush (Artemisia spp.) habitats on which this species depends. In response to this need, we evaluated the potential benefits of two restoration scenarios on Greater Sage-Grouse in the interior Columbia Basin and adjacent portions of the Great Basin of the western United States. Scenario 1 assumed a 50% reduction in detrimental grazing effects (through changes in stocking rates and grazing systems) and a six-fold increase in areas treated with active restoration (e.g., prescribed burning, native seedings, wildfire suppression) compared with future management proposed by the FS–BLM. Scenario 2 assumed a 100% reduction in detrimental grazing effects and the same increase in active restoration as scenario 1. To evaluate benefits, we estimated the risk of population extirpation for sage grouse 100 years in the future under the two scenarios and compared this risk with that estimated for proposed (100-year) FS–BLM management. We used estimates of extirpation risk for historical (circa 1850–1890) and current time periods as a context for our comparison. Under historical conditions, risk of extirpation was very low on FS–BLM lands, but increased to a moderate probability under current conditions. Under proposed FS–BLM management, risk of extirpation on FS–BLM lands increased to a high probability 100 years in the future. Benefits of the two restoration scenarios, however, constrained the future risk of extirpation to a moderate probability. Our results suggest that expansive and sustained habitat restoration can maintain desired conditions and reduce future extirpation risk for sage grouse on FS–BLM lands in western North America. The continued spread of exotic plants, however, presents a formidable challenge to successful restoration and warrants substantial research and management attention. Resumen: Los habitats del urogallo (Centrocercus urophasianus) han disminuido a lo largo de la region occidental de Norteamerica, y la mayoria de los habitats restantes ocurren en terrenos administrados por el Servicio Forestal de E.U.A. (SF) y el Buro de Administracion de Tierras ( BAT ). Por lo tanto, los encargados de las tierras SF–BAT necesitan estrategias eficaces para recuperar los habitats de artemisa (Artemisia spp.) de los cuales depende esta especie. En respuesta a esta necesidad, evaluamos los beneficios potenciales de dos escenarios de restauracion sobre el urogallo en el interior de la Cuenca del Columbia y porciones adyacentes de la Gran Cuenca del occidente de los Estados Unidos. El escenario 1 supone una reduccion del 50% en los efectos perjudiciales del pastoreo ( por medio de cambios en las tasas de aprovisionamiento y en los sistemas de pastoreo) y un incremento de seis veces en la superficie de las areas tratadas con restauracion activa ( por ejemplo, quemas prescritas, plantulas nativas, supresion de fuego no controlado) comparada con la administracion futura propuesta por el SF–BAT. El escenario 2 supone una reduccion del 100% en los efectos de pastoreo perjudiciales y el mismo aumento en la restauracion activa que en el escenario 1. Para evaluar los beneficios, estimamos el riesgo de extirpacion de la poblacion de urogallos en 100 anos bajo los dos escenarios y comparamos este riesgo con el riesgo estimado por la propuesta de manejo de SF–BAT (100-anos). Utilizamos estimaciones del riesgo de extirpacion en periodos historicos (entre 1850 y 1890) y actuales como contexto para nuestra comparacion. Bajo condiciones historicas, el riesgo de extirpacion fue muy bajo en los terrenos SF–BAT pero aumento a una probabilidad moderada bajo condiciones actuales. Bajo la administracion propuesta por SF–BAT, el riesgo de extirpacion en los terrenos SF–BAT aumento a una alta probabilidad 100 anos en el futuro. Sin embargo, los beneficios de los dos escenarios de restauracion constrinen el riesgo de extirpacion a una probabilidad moderada. Nuestros resultados sugieren que la restauracion expansiva y sostenida del habitat puede mantener condiciones deseadas y reduce el riesgo de extirpacion de urogallos en terrenos SF–BAT en la region occidental de Norteamerica. Sin embargo, la continua extension de plantas exoticas representa un reto formidable para la restauracion exitosa y justifica considerable investigacion y atencion de manejo.

We analyzed effects of three land management alternatives on 31 terrestrial vertebrates of conservation concern within the interior Columbia river basin study area. The three alternatives were proposed in a Supplemental Draft Environmental Impact Statement (SDEIS) that was developed for lands in the study area administered by the US Department of Agriculture (USDA) Forest Service (FS) and US Department of Interior (USDA) Bureau of Land Management (BLM). To evaluate effects of these alternatives, we developed Bayesian belief network (BBN) models, which allowed empirical and hypothesized relations to be combined in probability-based projections of conditions. We used the BBN models to project abundance and distribution of habitat to support potential populations (population outcomes) for each species across the entire study area. Population outcomes were defined in five classes, referred to as outcomes A–E. Under outcome A, populations are abundant and well distributed, with little or no likelihood of extirpation. By contrast, populations under outcome E are scarce and patchy, with a high likelihood of local or regional extirpation. Outcomes B–D represent gradients of conditions between the extremes of classes A and E. Most species (65%, or 20 of 31) were associated with outcome A historically and with outcomes D or E currently (55%, or 17 of 31). Population outcomes projected 100 years into the future were similar for all three alternatives but substantially different from historical and current outcomes. For species dependent on old-forest conditions, population outcomes typically improved one outcome class — usually from E or D to D or C — from current to the future under the alternatives. By contrast, population outcomes for rangeland species generally did not improve under the alternatives, with most species remaining in outcomes C, D, or E. Our results suggest that all three management alternatives will substantially improve conditions for most forest-associated species but provide few improvements for rangeland-associated vertebrates. Continued displacement of native vegetation by exotic plants, as facilitated by a variety of human-associated disturbances, will be an on-going challenge to the improvement of future conditions for rangeland species.

We developed procedures for using Bayesian belief networks (BBNs) to model habitat and population viability of selected at-risk fish and wildlife species. The BBN models represent the ecological causal web of key environmental correlates (KECs) that most influence habitat capability, potential population response for each species, and influence of habitat planning alternatives. BBN models represent site-specific KECs, habitat capability at the subwatershed level, and pattern of habitat capability across all subwatersheds. BBNs use Dirichlet prior probability distributions and standard Bayesian updating of posterior probabilities. We derived estimates of prior and conditional probabilities from a mix of empirical data and expert judgment, mostly the latter. Sensitivity analyses identified planning decisions and KECs that most influence species outcomes, and can help prioritize monitoring activities. BBN models, however, substitute for neither field studies nor empirical, quantitative population viability analyses of population demography and genetics.

A habitat network is defined as a spatially explicit portrayal of environmental conditions across large landscapes that can be used to understand the status and trends of species of conservation concern, particularly in relation to how species' needs are met through management of habitat abundance and distribution. Habitat networks are specifically designed to account for and summarize spatial information across landscapes compatible in size and arrangement with the targeted species' activities and movements. Habitat networks provide several potential benefits, including conditions for large numbers of species of conservation concern can be addressed efficiently across space and time; a wide variety of habitat characteristics can be holistically integrated; and ecological characterizations provided as part of the network do not dictate a particular form of management, but rather provide the basis for development of a variety of follow-up on management strategies and options. Habitat networks exemplify spatial relationships in wildlife ecology; habitat patches are not only defined and located, but also mapped in relation to each other. Mapping habitat networks in a GIS thus allows for “spatial depictions of theoretical constructs,” such as core habitat and linkages.

The authors present estimates of the economic costs to agriculture and industries affected by tourism of the outbreak of foot and mouth disease (FMD) in the United Kingdom (UK) in 2001. The losses to agriculture and the food chain amount to about Pound Sterling3.1 billion. The majority of the costs to agriculture have been met by the Government through compensation for slaughter and disposal as well as clean-up costs. Nonetheless, agricultural producers will have suffered losses, estimated at Pound Sterling355 million, which represents about 20% of the estimated total income from farming in 2001. Based on data from surveys of tourism, businesses directly affected by tourist expenditure are estimated to have lost a similar total amount (between Pound Sterling2.7 and Pound Sterling3.2 billion) as a result of reduced numbers of people visiting the countryside. The industries which supply agriculture, the food industries and tourist-related businesses will also have suffered losses. However, the overall costs to the UK economy are substantially less than the sum of these components, as much of the expenditure by tourists was not lost, but merely displaced to other sectors of the economy. Overall, the net effect of FMD is estimated to have reduced the gross domestic product in the UK by less than 0.2% in 2001.

Hann, Wendel J.; Wisdom, Michael J.; Rowland, Mary M. 2003. Disturbance departure and fragmentation of natural systems in the interior Columbia basin. Res. Pap. PNW-RP-545. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 19 p. We integrated landscape data from science assessments of the interior Columbia basin (basin) into one variable that functions as a robust index of departure from native conditions. This variable, referred to as the disturbance departure and fragmentation index, is a spatially explicit measure of landscape quality and resiliency. Primary causes of departure and fragmentation include fire exclusion, timber harvest, mining, oil and gas development, livestock grazing, invasive species, road networks, and the interface of these activities with agricultural and urban development. We derived four classes of the disturbance departure and fragmentation index: very high, high, moderate, and low. Very high departure and fragmentation was associated with low-elevation subwatersheds dominated by agricultural and urban lands. High departure and fragmentation was found in subwatersheds containing a mix of agricultural lands with low-elevation forests, woodlands, or rangelands. Subwatersheds with moderate departure and fragmentation were associated with lowto mid-elevation forests, woodlands, or rangelands in public ownership. Subwatersheds with low departure and fragmentation typically occurred at higher elevations, on public lands within or near wilderness areas, roadless areas, or national parks. Because the disturbance departure and fragmentation index represents the composite effects of management activities that do not mimic native or natural processes, the index appears useful as a planning tool for integrated restoration of wildland landscapes.