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Changes in topography, such as terrain elevation and slope, are an important source of landscape complexity influencing the ecology of animals, particularly in mountainous landscapes. In such landscapes animals navigate changes in elevation and slope in their daily movement. Despite the importance of topographic variation, studies of animal ecology in mountainous landscapes tend not to explicitly consider those effects on species detection. We deployed a broad‐extent, coarse resolution camera‐trapping system across a landscape with considerable complexity and quantified the influence of topographic variables on detection probability conditional on occurrence for multiple mammal species. Specifically, we examined the fine‐scale effects of terrain steepness and topographic position (i.e. ridges, mid‐slopes or valleys) on detection probability for 14 mammal species at camera‐traps. We found that detection probability increased on gently sloping terrain for six species and decreased on the steepest slopes sampled for three of these species and three additional species. Among four other mammal species, detection probability changed according to local topographic position though the directionality of these responses varied among these species. Several species, primarily meso‐carnivores as well as larger‐bodied species, like mule deer and black bears, were more detectable on gentle slopes than flat terrain. This pattern suggests that many species may use moderately steep terrain for the resources or heterogeneity they provide. Topographic position had comparatively less effect on species detection probabilities, suggesting that this variable does not have a strong effect on fine‐scale space use of animal species in mountainous regions. These relationships suggest that researchers should consider local terrain when siting camera traps in mountainous landscapes and analyzing survey data from such landscapes. Studies that compare the detection of mammal species at cameras deployed in close proximity will improve our understanding of fine‐scale topographic effects on mammal movement and detection. [ABSTRACT FROM AUTHOR]

Greater sage-grouse Centrocercus urophasianus populations across North America have been declining due to degradation and fragmentation of sagebrush habitat. As part of a study quantifying greater sage-grouse demographics prior to construction of a wind energy facility, we estimated apparent net nest productivity and survival rate of chicks associated with radio-equipped female sage-grouse in Carbon County, Wyoming, USA. We estimated apparent net nest productivity using a weighted mean of the average brood size and used a modified logistic-exposure method to estimate daily chick survival over a 70-day time period. Apparent nest productivity was 2.79 chicks per female (95% CI: 1.46-4.12) in 2011, 2.00 chicks per female (95% CI: 1.00-3.00) in 2012, and 1.54 chick per female (95% CI: 0.62-2.46) in 2013. Chick survival to 70 days post-hatch was 19.10% (95% CI: 6.22-37.42%) in 2011, 4.20% (95% CI: 0.84-12.31%) in 2012, and 16.05% (95% CI: 7.67-27.22%) in 2013. These estimates were low, yet within the range of other published survival rates. Chick survival was primarily associated with year and chick age, with minor effects of average temperature between surveys and hatch date. The variability in chick survival rates across years of our study suggests annual weather patterns may have large impacts on chick survival. Thus, management actions that increase the availability of food and cover for chicks may be necessary, especially during years with drought and above-average spring temperatures. [ABSTRACT FROM AUTHOR]

Insight into the spatial ecology of predators might help biologists to design wildlife reserves that maximize conservation success. We investigated the spatial ecology of endangered black-footed ferrets Mustela nigripes during the post-breeding seasons (June-October) of 2007 and 2008 on a 452-ha colony of black-tailed prairie dogs Cynomys ludovicianus in South Dakota, USA. Ferrets of both sexes frequently used areas with an abundance of active openings to prairie dog burrows, suggesting a positive response to refuge and prey. Densities of active burrow openings were similar in areas of same-sex overlap and areas of exclusive space use, which might suggest limited defense of resources by ferrets. However, this result could be expected in our study because much of the study colony contained high densities of active burrow openings. Same-sex home ranges overlapped in area, but the intensity of space use overlap was low. For male ferrets with overlapping home ranges, both males tended to spend low amounts of time in areas of overlap. In contrast, for pairs of overlapping female home ranges, one female frequently used areas of overlap while the second apparently avoided them, suggesting a dominance hierarchy of some sort. Core areas were essentially exclusive. Our data are consistent with the hypothesis of intrasexual territoriality by ferrets in habitats of high quality, which would limit the number of ferrets a habitat supports. Where wildlife managers aim to maximize densities of free-ranging ferrets, it might be beneficial to create reserves that 1) provide each ferret with sufficient prey and refuge, 2) reduce social conflict and competition for space, and 3) facilitate dispersal. [ABSTRACT FROM AUTHOR]

Although statistical population reconstruction (SPR) provides a flexible framework for estimating demographics of harvested populations using age-at-harvest data, that information alone is insufficient. Auxiliary data are needed to ensure all model parameters are estimable and to improve the precision and accuracy of the estimates. We examined the influence of two types of auxiliary information, independent estimates of annual abundance and annual harvest mortality from radio-telemetry studies, on the stability and precision of abundance estimates from SPR. Further, we evaluated whether the timing of auxiliary studies in the reconstruction affected the precision of abundance estimates. Monte Carlo studies simulated auxiliary data with precision levels defined by the coefficients of variation (CV) of 0.05, 0.125, 0.25 and 0.50 corresponding to the three levels of precision suggested by Robson & Regier (1964) for accurate research, accurate management and rough management and a minimal information scenario. For comparable levels of precision, radio-telemetry studies used to estimate harvest mortality stabilized the reconstructed population trends better than independent abundance surveys. However, independent abundance surveys were superior at improving the precision of reconstructed abundance estimates. We found that the timing of auxiliary studies did not influence the stability of SPR estimates, which has important implications for managers designing studies to collect auxiliary data. Our research highlights that different types and quality of auxiliary studies affects the precision and stability of SPR models differently. [ABSTRACT FROM AUTHOR]

Roads increase risk to animals via direct and indirect mechanisms yet, both positive and negative effects of animal space use in relation to roads have been reported. These contrasting reportsmay not actually represent animal ecology, but could be a product of the primary variable used to test the relationship between animals and roads. Animal-road associations are often evaluated using Euclidean distance. Euclidean, or straight-line, distance fails to account for the screening effects of vegetation and topography and may document spurious relationships.We evaluated the influence of Euclidean distance, visibility from road and forage quality on summer space use for male elk Cervus elaphus and female elk subherds in Custer State Park, South Dakota, USA. Models that included interactions with visibility from roadmetrics out performed models that included only Euclidean distance to road as main effects. Elk response to roads varied by sex and road type, which functioned as an index for vehicle use. Male elk selected habitat away from roadswith the greatest vehicle use, an effect that was greater if habitat was visible from those roads. Female elk tended to select habitat with high forage quality in areas visible from roads closed to vehicle use. Interestingly, both male and female elk selected habitat away from roads with secondary vehicle use and near to roads devoid of traffic, regardless of visibility. Our analysis highlights the importance of including both Euclidean distance and visibility from road metrics. Road effects research may be incomplete without consideration of visibility from roads, particularly for large mammals in landscapes with intense road use. [ABSTRACT FROM AUTHOR]

Statistical population reconstruction can be a valuable tool for monitoring the status and trends of game populations at large spatial scales using age-at-harvest data. Despite their utility and increasing use in demographic studies, it is necessary that these models be evaluated before their results are applied. We recommend practitioners evaluate their fitted population models using a variety of approaches, including residual analyses, point-deletion techniques and sensitivity analyses, and we illustrate these techniques using several case studies. Although we stress the value of these quantitative procedures, the final evaluation criterion should be the biological realism of the estimated demographic parameters and trends. Auxiliary field data should be used whenever possible in this final model check. After investigators are satisfied that the selected model(s) is/are adequate, this auxiliary data can be incorporated in a final stage of the analyses to further improve accuracy and precision of the population projections. The procedures we outline and recommendations we make will improve the credibility and utility of results of population reconstruction modeling. [ABSTRACT FROM AUTHOR]

Knowledge of movements, range size and spatial overlap of sympatric deer is integral to understanding chronic wasting disease (CWD) in endemic areas and can assist resource managers in modeling the spread of the disease. We radiocollared 70 deer (30 mule deer Odocoileus hemionus and 40 white-tailed deer O. virginianus) in the North Platte River Valley in western Nebraska, USA, from 2004 to 2007 to document movements, size and spatial overlap of home range and resource selection of these sympatric species of deer. We compared home-range size and overlap and resource selection among male and female mule deer and white-tailed deer to examine relative use of space in order to understand the potential for indirect spread of CWD better. We identified forested, riparian habitats as high selection of use and these habitats could likely contribute to the potential spreading of CWD between sympatric deer that concentrate in these areas.Wefound that migration, size of home range of female mule deer, and similarities in resource selection could contribute to sustaining or spreading CWD in Nebraska. The role of female mule deer in the spread of CWD coupled with selection for riparian corridors by both species should be investigated further, because these factors may be a primary determinant of disease spread in the historical range of mule deer. [ABSTRACT FROM AUTHOR]