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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.

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 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.

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.