The essential oil of greater galanga (Alpinia galanga) from Malaysia

The essential oil of A. galanga, a common spice in Malaysia, was prepared from fresh and dried rhizomes and analysed by means of capillary GC and GC/MS. Forty components were identified (only three of which were previously reported), accounting for 83–93% of the oil, depending on its method of preparation. Apart from monoterpenes, monoterpene alcohols and esters, and sesquiterpenes, also methyleugenol, eugenol acetate, chavicol (4-allylphenol) and chavicol acetate were present. This is the first time the latter substance has been reported in nature. Standardization of GC is proposed and tentatively applied towards a more systematic use of the Kováts indices as an aid in the identification of the constituents of essential oils.     

Mapping canopy nitrogen‐scapes to assess foraging habitat for a vulnerable arboreal folivore in mixed‐species Eucalyptus forests

Herbivore foraging decisions are closely related to plant nutritional quality. For arboreal folivores with specialized diets, such as the vulnerable greater glider (Petauroides volans), the abundance of suitable forage trees can influence habitat suitability and species occurrence. The ability to model and map foliar nitrogen would therefore enhance our understanding of folivore habitat use at finer scales. We tested whether high‐resolution multispectral imagery, collected by a lightweight and low‐cost commercial unoccupied aerial vehicle (UAV), could be used to predict total and digestible foliar nitrogen (N and digN) at the tree canopy level and forest stand‐scale from leaf‐scale chemistry measurements across a gradient of mixed‐species Eucalyptus forests in southeastern Australia. We surveyed temperate Eucalyptus forests across an elevational and topographic gradient from sea level to high elevation (50–1200 m a.s.l.) for forest structure, leaf chemistry, and greater glider occurrence. Using measures of multispectral leaf reflectance and spectral indices, we estimated N and digN and mapped N and favorable feeding habitat using machine learning algorithms. Our surveys covered 17 Eucalyptus species ranging in foliar N from 0.63% to 1.92% dry matter (DM) and digN from 0.45% to 1.73% DM. Both multispectral leaf reflectance and spectral indices were strong predictors for N and digN in model cross‐validation. At the tree level, 79% of variability between observed and predicted measures of nitrogen was explained. A spatial supervised classification model correctly identified 80% of canopy pixels associated with high N concentrations (≥1% DM). We developed a successful method for estimating foliar nitrogen of a range of temperate Eucalyptus species using UAV multispectral imagery at the tree canopy level and stand scale. The ability to spatially quantify feeding habitat using UAV imagery allows remote assessments of greater glider habitat at a scale relevant to support ground surveys, management, and conservation for the vulnerable greater glider across southeastern Australia.     

Sage-Grouse Habitat Selection During Winter in Alberta

ABSTRACT Greater sage-grouse (Centrocercus urophasianus) are dependent on sagebrush (Artemisia spp.) for food and shelter during winter, yet few studies have assessed winter habitat selection, particularly at scales applicable to conservation planning. Small changes to availability of winter habitats have caused drastic reductions in some sage-grouse populations. We modeled winter habitat selection by sage-grouse in Alberta, Canada, by using a resource selection function. Our purpose was to 1) generate a robust winter habitat-selection model for Alberta sage-grouse; 2) spatially depict habitat suitability in a Geographic Information System to identify areas with a high probability of selection and thus, conservation importance; and 3) assess the relative influence of human development, including oil and gas wells, in landscape models of winter habitat selection. Terrain and vegetation characteristics, sagebrush cover, anthropogenic landscape features, and energy development were important in top Akaike's Information Criterion-selected models. During winter, sage-grouse selected dense sagebrush cover and homogenous less rugged areas, and avoided energy development and 2-track truck trails. Sage-grouse avoidance of energy development highlights the need for comprehensive management strategies that maintain suitable habitats across all seasons.     

Multi-scale assessment of greater sage-grouse fence collision as a function of site and broad scale factors

Previous research in Europe and North America suggested grouse are susceptible to collision with infrastructure, and anecdotal observation suggested greater sage-grouse (Centrocercus urophasianus) fence collision in breeding habitats may be prevalent. However, no previous research systematically studied greater sage-grouse fence collision in any portion of their range. We used data from probability-based sampling of fences in greater sage-grouse breeding habitats of southern Idaho, USA, to model factors associated with collision at microsite and broad spatial scales. Site-scale modeling suggested collision may be influenced by technical attributes of fences, with collisions common at fence segments absent wooden fence posts and with segment widths >4 m. Broad-scale modeling suggested relative probability of collision was influenced by region, a terrain ruggedness index (TRI), and fence density per square km. Conditional on those factors, collision counts were also influenced by distance to nearest active sage-grouse lek. Our models provide a conceptual framework for prioritizing sage-grouse breeding habitats for collision mitigation such as fence marking or moving, and suggest mitigation in breeding habitats should start in areas with moderate-high fence densities (>1 km/km²) within 2 km of active leks. However, TRI attenuated other covariate effects, and mean TRI/km² >10 m nearly eliminated sage-grouse collision. Thus, our data suggested mitigation should focus on sites with flat to gently rolling terrain. Moreover, site-scale modeling suggested constructing fences with larger and more conspicuous wooden fence posts and segment widths <4 m may reduce collision. © 2012 The Wildlife Society.     

The importance of within-year repeated counts and the influence of scale on long-term monitoring of sage-grouse

Long-term population monitoring is the cornerstone of animal conservation and management. The accuracy and precision of models developed using monitoring data can be influenced by the protocols guiding data collection. The greater sage-grouse (Centrocercus urophasianus) is a species of concern that has been monitored over decades, primarily, by counting the number of males that attend lek (breeding) sites. These lek count data have been used to assess long-term population trends and for multiple mechanistic studies. However, some studies have questioned the efficacy of lek counts to accurately identify population trends. In response, monitoring protocols were changed to have a goal of counting lek sites multiple times within a season. We assessed the influence of this change in monitoring protocols on model accuracy and precision applying generalized additive models to describe trends over time. We found that at large spatial scales including >50 leks, the absence of repeated counts within a year did not significantly alter population trend estimates or interpretation. Increasing sample size decreased the model confidence intervals. We developed a population trend model for Wyoming greater sage-grouse from 1965 to 2008, identifying significant changes in the population indices and capturing the cyclic nature of this species. Most sage-grouse declines in Wyoming occurred between 1965 and the 1990s and lek count numbers generally increased from the mid-1990s to 2008. Our results validate the combination of monitoring data collected under different protocols in past and future studies—provided those studies are addressing large-scale questions. We suggest that a larger sample of individual leks is preferable to multiple counts of a smaller sample of leks. © 2011 The Wildlife Society.