Landscapes for Energy and Wildlife: Conservation Prioritization for Golden Eagles across Large Spatial Scales

Proactive conservation planning for species requires the identification of important spatial attributes across ecologically relevant scales in a model-based framework. However, it is often difficult to develop predictive models, as the explanatory data required for model development across regional management scales is rarely available. Golden eagles are a large-ranging predator of conservation concern in the United States that may be negatively affected by wind energy development. Thus, identifying landscapes least likely to pose conflict between eagles and wind development via shared space prior to development will be critical for conserving populations in the face of imposing development. We used publically available data on golden eagle nests to generate predictive models of golden eagle nesting sites in Wyoming, USA, using a suite of environmental and anthropogenic variables. By overlaying predictive models of golden eagle nesting habitat with wind energy resource maps, we highlight areas of potential conflict among eagle nesting habitat and wind development. However, our results suggest that wind potential and the relative probability of golden eagle nesting are not necessarily spatially correlated. Indeed, the majority of our sample frame includes areas with disparate predictions between suitable nesting habitat and potential for developing wind energy resources. Map predictions cannot replace on-the-ground monitoring for potential risk of wind turbines on wildlife populations, though they provide industry and managers a useful framework to first assess potential development.     

Spatial Heterogeneity in Ecologically Important Climate Variables at Coarse and Fine Scales in a High-Snow Mountain Landscape

Climate plays an important role in determining the geographic ranges of species. With rapid climate change expected in the coming decades, ecologists have predicted that species ranges will shift large distances in elevation and latitude. However, most range shift assessments are based on coarse-scale climate models that ignore fine-scale heterogeneity and could fail to capture important range shift dynamics. Moreover, if climate varies dramatically over short distances, some populations of certain species may only need to migrate tens of meters between microhabitats to track their climate as opposed to hundreds of meters upward or hundreds of kilometers poleward. To address these issues, we measured climate variables that are likely important determinants of plant species distributions and abundances (snow disappearance date and soil temperature) at coarse and fine scales at Mount Rainier National Park in Washington State, USA. Coarse-scale differences across the landscape such as large changes in elevation had expected effects on climatic variables, with later snow disappearance dates and lower temperatures at higher elevations. However, locations separated by small distances (∼20 m), but differing by vegetation structure or topographic position, often experienced differences in snow disappearance date and soil temperature as great as locations separated by large distances (>1 km). Tree canopy gaps and topographic depressions experienced later snow disappearance dates than corresponding locations under intact canopy and on ridges. Additionally, locations under vegetation and on topographic ridges experienced lower maximum and higher minimum soil temperatures. The large differences in climate we observed over small distances will likely lead to complex range shift dynamics and could buffer species from the negative effects of climate change.     

Spatial Pattern of Attacks of the Invasive Woodwasp Sirex noctilio,at Landscape and Stand Scales

Invasive insect pests are responsible for important damage to native and plantation forests, when population outbreaks occur. Understanding the spatial pattern of attacks by forest pest populations is essential to improve our understanding of insect population dynamics and for predicting attack risk by invasives or planning pest management strategies. The woodwasp Sirex noctilio is an invasive woodwasp that has become probably the most important pest of pine plantations in the Southern Hemisphere. Our aim was to study the spatial dynamics of S. noctilio populations in Southern Argentina. Specifically we describe: (1) the spatial patterns of S. noctilio outbreaks and their relation with environmental factors at a landscape scale; and (2) characterize the spatial pattern of attacked trees at the stand scale. We surveyed the spatial distribution of S. noctilio outbreaks in three pine plantation landscapes, and we assessed potential associations with topographic variables, habitat characteristics, and distance to other outbreaks. We also looked at the spatial distribution of attacked trees in 20 stands with different levels of infestation, and assessed the relationship of attacks with stand composition and management. We found that the spatial pattern of pine stands with S. noctilio outbreaks at the landscape scale is influenced mainly by the host species present, slope aspect, and distance to other outbreaks. At a stand scale, there is strong aggregation of attacked trees in stands with intermediate infestation levels, and the degree of attacks is influenced by host species and plantation management. We conclude that the pattern of S. noctilio damage at different spatial scales is influenced by a combination of both inherent population dynamics and the underlying patterns of environmental factors. Our results have important implications for the understanding and management of invasive insect outbreaks in forest systems.     

Measuring Spider Richness: Effects of Different Sampling Methods and Spatial and Temporal Scales

Assessing the richness of invertebrate taxa to aid conservation and management requires a better understanding of the potential sources of error. Patterns of richness for heathland spiders at the species and family levels were compared across three sampling methods, four spatial scales, and monthly intervals (for 16 months). A total of 33 families and 130 species was collected: pitfall traps collected 94% of species, sweep net, 25%, and visual search, 41%. The sampling methods produced variable results. Pitfall trap and sweep net techniques identified significant, yet contrasting spatial differences in the number of families and species at one spatial scale. Pitfall trap data reflected strong temporal variation that influenced spatial patterns in richness (across one spatial scale for families and two for species). The use of broader temporal scales introduced a potential failure to detect significant differences in the richness of ground active spiders, and this risk varied spatially. The sweep net is not recommended for this habitat, although a method that targets the foliage is required for a more complete faunal assessment. Visual searches detected no significant patterns in richness, yet given its potential and increasing use for rapid biodiversity surveys, ways to improve sampling efficiency are suggested.     

Carbon Stocks in an African Woodland Landscape: Spatial Distributions and Scales of Variation

Current knowledge of Africa’s carbon (C) pools is limited despite its importance in the global C budget. To increase the understanding of C stocks in African woodlands, we asked how C stocks in soil and vegetation vary across a miombo woodland landscape and to what degree and at what scales are these stocks linked? We sampled along a 5-km transect using a cyclic sampling scheme to allow geostatistical analyses. Soil C stocks in the top 5?cm (12.1?±?0.6?Mg?C?ha^?1 (±?SE)) and 30?cm depths (40.1?±?2.5?Mg?C?ha^?1) varied significantly at scales of a few meters (autocorrelation distance 14?m in 0–5-cm and 26?m in 0–30-cm interval), and aboveground (AG) woody C stocks (20.7?±?1.8?Mg?C?ha^?1) varied significantly at kilometer scales (1,426?m). Soil textural distributions were linked to topography (r ²?=?0.54) as were large-tree AG C stocks (r ²?=?0.70). AG C stocks were constrained to an upper boundary by soil texture with greater AG C being associated with coarser textured soils. Vegetation and soil C stocks were coupled in the landscape in the top 5?cm of soil (r ²?=?0.24) but not with deeper soil C stocks, which were coupled to soil clay content (r ²?=?0.38). This study is one of the most complete transect studies in an African miombo woodland, and suggests that C stock distributions are strongly linked to topography and soil texture. To optimize sampling strategies for C stock assessments in miombo, soil C should be sampled at more than 26?m apart, and AG C should be sampled at more than 1,426?m apart in plots larger than 0.5?ha.     

Landscape Ecotoxicology and Assessment of Risk at Multiple Scales

Traditional approaches to ecotoxicology and ecological risk assessment frequently have ignored the complexities arising due to the spatial heterogeneity of natural systems. In recent years, however, ecologists have become increasingly aware of the influence of spatial organization on ecological processes. Landscape ecology provides a conceptual and theoretical framework for the analysis of spatial patterns, the characterization of spatial aspects of ecosystem function, and the understanding of landscape dynamics. Incorporating the insights of landscape ecology into ecotoxicology will enhance our ability to understand and ultimately predict the effects of toxic substances in ecological systems. Ecological risk assessments need to explicitly consider multiple spatial scales, accounting for heterogeneity within contaminated areas and for the larger landscape context. A simple simulation model is presented to illustrate the effects of spatial heterogeneity by linking an individual-based toxicokinetic model with a spatially distributed metapopulation model. Dispersal of organisms between contaminated and uncontaminated patches creates a situation where risk analysis must consider a spatial extent broader than the toxicant-contaminated area. In general, the addition of a toxicant to a source patch (i.e., a net exporter of individuals) will have a greater impact than the same toxicant addition to a sink patch (i.e., a net importer of individuals).     

Estimates of Abundance and Harvest Rates of Female Black Bears Across a Large Spatial Extent

American black bears (Ursus americanus) are an iconic wildlife species in the southern Appalachian highlands of the eastern United States and have increased in number and range since the early 1980s. Given an increasing number of human-bear conflicts in the region, many management agencies have liberalized harvest regulations to reduce bear populations to socially acceptable levels. Wildlife managers need reliable population data for assessing the effects of management actions for this high-profile species. Our goal was to use DNA extracted from hair collected at barbed-wire enclosures (i.e., hair traps) to identify individual bears and then use spatially explicit capture-recapture methods to estimate female black bear density, abundance, and harvest rate. We established 888 hair traps across 66,678 km² of the southern Appalachian highlands in Georgia, North Carolina, South Carolina, and Tennessee, USA, in 2017 and 2018, arranged in 174 clusters of 2–9 traps/cluster. We collected 9,113 hair samples from those sites over 6 weeks of sampling, of which 1,954 were successfully genotyped to 462 individual female bears. Our spatially explicit estimator included a percent forest covariate to explain inhomogeneous bear density across the region. Densities ranged up to 0.410 female bears/km² and regional abundance was 5,950 (95% CI = 4,988–7,098) female bears. Based on hunter kill data from 2016 to 2018, mean annual harvest rates for females were 12.7% in Georgia, 17.6% in North Carolina, 17.6% in South Carolina, and 22.8% in Tennessee. Our estimated harvest rates for most states approached or exceeded theoretical maximum sustainable levels, and population trend data (i.e., bait-station indices) indicated decreasing growth rates since about 2009. These data suggest that the increased harvest goals and poor hard mast production over a series of prior years reduced bear population abundance in many states. We were able to obtain reasonable population abundance and density estimates because of spatially explicit capture-recapture methods, cluster sampling, and a large spatial extent. Continued monitoring of bear populations (e.g., annual bait-station surveys and periodic population estimation using spatially explicit methods) by state jurisdictions would help to ensure that population trajectories are consistent with management goals. © 2021 The Wildlife Society.     

Bird Community Composition in a Shaded Coffee Agro-ecological Matrix in Puebla,Mexico: The Effects of Landscape Heterogeneity at Multiple Spatial Scales

This study examined the importance of habitat heterogeneity on the avian community composition, and investigated the scale at which species abundances respond to habitat variables. The study was conducted within a diverse landscape matrix of a shaded coffee region in Mexico. To detect at which characteristic spatial scale different species and foraging guilds respond most strongly we analyzed the effect of plot-, patch- and landscape-level variables at different spatial extent (i.e., different kilometer radii) on species composition and foraging guilds. We used redundancy analysis to identify species–environment correlations, and to identify predictor variables that best explained the bird community structure, quantified the influence of plot-, patch- and landscape-level variables on the bird community composition. In addition, we used the 4th-corner method to detect significant relationships between the dietary guilds and plot-, patch- and landscape-level variables. We recorded 12,335 individuals of 181 bird species; 105 bird species were recorded foraging within the shaded coffee plantations. We found that plot- and landscape-level variables significantly explained the bird community composition best across all scales, and were significantly correlated with the abundance of the dietary guilds. In contrast, patch-level variables were less important. Habitat composition variables (i.e., coffee, forest and agricultural area) were among the most important predictors. Canopy structure was more important than other vegetation structure variables in explaining dietary guild structure. Hence, the maintenance of a heterogeneous landscape with a high-quality matrix within an agro-ecological region enhances bird conservation.     

Measuring the Effectiveness of Conservation: A Novel Framework to Quantify the Benefits of Sage-Grouse Conservation Policy and Easements in Wyoming

Increasing energy and housing demands are impacting wildlife populations throughout western North America. Greater sage-grouse (Centrocercus urophasianus), a species known for its sensitivity to landscape-scale disturbance, inhabits the same low elevation sage-steppe in which much of this development is occurring. Wyoming has committed to maintain sage-grouse populations through conservation easements and policy changes that conserves high bird abundance “core” habitat and encourages development in less sensitive landscapes. In this study, we built new predictive models of oil and gas, wind, and residential development and applied build-out scenarios to simulate future development and measure the efficacy of conservation actions for maintaining sage-grouse populations. Our approach predicts sage-grouse population losses averted through conservation action and quantifies return on investment for different conservation strategies. We estimate that without conservation, sage-grouse populations in Wyoming will decrease under our long-term scenario by 14–29% (95% CI: 4–46%). However, a conservation strategy that includes the “core area” policy and $250 million in targeted easements could reduce these losses to 9–15% (95% CI: 3–32%), cutting anticipated losses by roughly half statewide and nearly two-thirds within sage-grouse core breeding areas. Core area policy is the single most important component, and targeted easements are complementary to the overall strategy. There is considerable uncertainty around the magnitude of our estimates; however, the relative benefit of different conservation scenarios remains comparable because potential biases and assumptions are consistently applied regardless of the strategy. There is early evidence based on a 40% reduction in leased hectares inside core areas that Wyoming policy is reducing potential for future fragmentation inside core areas. Our framework using build-out scenarios to anticipate species declines provides estimates that could be used by decision makers to determine if expected population losses warrant ESA listing.     

The Great Ape Project and Disability Rights: Ominous Undercurrents of Eugenics in Action

The Great Ape Project is an international animal rights movement with the goal of extending rights to nonhuman primates. While the authors of this essay are sympathetic with scholars who seek to ensure humane treatment for these species, they are concerned with the growing tendency by those in the project to draw analogies between nonhuman primates and humans with disabilities. It is felt that scholars in the Great Ape Project, ignoring findings from anthropologists who have begun to study the significant sociocultural matrix that has defined and often limited individuals with disabilities, rely on assumptions about disability that can be traced back to the eugenics movement.
The authors of this essay argue that if scholars in the Great Ape Project want to make comparisons between humans and apes, it should be with all humans. They feel it is both unfortunate and scientifically inaccurate for those in the Great Ape Project to blur the boundary between apes and people by dehumanizing individuals with disabilities, individuals for whom human rights are often the most precarious, [great apes, Great Ape Project, disability, eugenics, human rights]     

Spectral and Structural Measures of Northwest Forest Vegetation at Leaf to Landscape Scales

We report a multiscale study in the Wind River Valley in southwestern Washington, where we quantified leaf to stand scale variation in spectral reflectance for dominant species. Four remotely sensed structural measures, the normalized difference vegetation index (NDVI), cover fractions from spectral mixture analysis (SMA), equivalent water thickness (EWT), and albedo were investigated using Airborne Visible Infrared Imaging Spectrometer (AVIRIS) data. Discrimination of plant species varied with wavelength and scale, with deciduous species showing greater separability than conifers. Contrary to expectations, plant species were most distinct at the branch scale and least distinct at the stand scale. At the stand scale, broadleaf and conifer species were spectrally distinct, as were most conifer age classes. Intermediate separability occurred at the leaf scale. Reflectance decreased from leaf to stand scales except in the broadleaf species, which peaked in near-infrared reflectance at the branch scale. Important biochemical signatures became more pronounced spectrally progressing from leaf to stand scales. Recent regenerated clear-cuts (less than 10 years old) had the highest albedo and nonphotosynthetic vegetation (NPV). After 50 years, the stands showed significant decreases in albedo, NPV, and EWT and increases in shade. Albedo was lowest in old-growth forests. Peak EWT, a proxy measure for leaf area index (LAI), was observed in 11- to 30-year-old stands. When compared to LAI, EWT and NDVI showed exponentially decreasing, but distinctly different, relationships with increasing LAI. This difference is biologically important: at 95% of the maximum predicted NDVI and EWT, LAI was 5.17 and 9.08, respectively. Although these results confirm the stand structural variation expected with forest succession, remote-sensing images also provide a spatial context and establish a basis to evaluate variance within and between age classes. Landscape heterogeneity can thus be characterized over large areas—a critical and important step in scaling fluxes from stand-based towers to larger scales.     

Sampling Plant Diversity and Rarity at Landscape Scales: Importance of Sampling Time in Species Detectability

Documenting and estimating species richness at regional or landscape scales has been a major emphasis for conservation efforts, as well as for the development and testing of evolutionary and ecological theory. Rarely, however, are sampling efforts assessed on how they affect detection and estimates of species richness and rarity. In this study, vascular plant richness was sampled in 356 quarter hectare time-unlimited survey plots in the boreal region of northeast Alberta. These surveys consisted of 15,856 observations of 499 vascular plant species (97 considered to be regionally rare) collected by 12 observers over a 2 year period. Average survey time for each quarter-hectare plot was 82 minutes, ranging from 20 to 194 minutes, with a positive relationship between total survey time and total plant richness. When survey time was limited to a 20-minute search, as in other Alberta biodiversity methods, 61 species were missed. Extending the survey time to 60 minutes, reduced the number of missed species to 20, while a 90-minute cut-off time resulted in the loss of 8 species. When surveys were separated by habitat type, 60 minutes of search effort sampled nearly 90% of total observed richness for all habitats. Relative to rare species, time-unlimited surveys had ∼65% higher rare plant detections post-20 minutes than during the first 20 minutes of the survey. Although exhaustive sampling was attempted, observer bias was noted among observers when a subsample of plots was re-surveyed by different observers. Our findings suggest that sampling time, combined with sample size and observer effects, should be considered in landscape-scale plant biodiversity surveys.     

The Spatial Distribution of Mistletoe in a Southern Indian Tropical Forest at Multiple Scales

Taxillus tomentosus is a mistletoe of significant management concern in southern India. This mistletoe affects the productivity of several nontimber forest products, most significantly Amla (Phyllanthus emblica and Phyllanthus indofischeri), whose fruits provide an important source of income for indigenous forest communities. Management interventions are required to secure the continued viability of Amla and thereby its role in livelihoods. To enhance the scientific basis for management, we characterized the distribution of T. tomentosus at three scales, examined potential mechanisms underlying this distribution, and compared both with those documented in other habitats. Mistletoes were aggregated at all three scales: on individual trees, within forest plots of 500 m², and at scales of 3–4 km. Seed deposition patterns provide an initial distribution ‘template’ that largely determines patterns at tree and plot scales. This initial pattern is subsequently altered as variation in host suitability and mistletoe mortality from forest fires influence establishment success and postestablishment survival. Local prevalence of infection contributed most to infection spread, and areas of high infection prevalence are highlighted as appropriate foci for management intervention. Although novel underlying mechanisms and variation in the scale of aggregation have been identified, mistletoe distribution in a tropical forest appears to be shaped by similar forces as those documented previously in temperate systems.     

Conservation in the Context of Climate Change: Practical Guidelines for Land Protection at Local Scales

Climate change will affect the composition of plant and animal communities in many habitats and geographic settings. This presents a dilemma for conservation programs – will the portfolio of protected lands we now have achieve a goal of conserving biodiversity in the future when the ecological communities occurring within them change? Climate change will significantly alter many plant communities, but the geophysical underpinnings of these landscapes, such as landform, elevation, soil, and geological properties, will largely remain the same. Studies show that extant landscapes with a diversity of geophysical characteristics support diverse plant and animal communities. Therefore, geophysically diverse landscapes will likely support diverse species assemblages in the future, although which species and communities will be present is not altogether clear. Following protocols advanced in studies spanning large regions, we developed a down-scaled, high spatial resolution measure of geophysical complexity based on Ecological Land Units (ELUs) and examined the relationship between plant species richness, ecological community richness, and ELU richness (number of different ELU types). We found that extant landscapes with high ELU richness had a greater variety of ecological community types and high species richness of trees, shrubs, and herbaceous plants. We developed a spatial representation of diverse ELU landscapes to inform local conservation practitioners, such as land trusts, of potential conservation targets that will likely support diverse faunas and floras despite the impact of climate change.     

Relative Impacts of Elephant and Fire on Large Trees in a Savanna Ecosystem

Elephant and fire are considered to be among the most important agents that can modify the African savanna ecosystem. Although the synergistic relationship between these two key ecological drivers is well documented, it has proved much more difficult to establish the relative effects they have on savanna vegetation structure at a fine-scale over time. In this study, we explore the comparative impacts of fire and elephant on 2,522 individually identified large trees (≥5 m in height) in the Kruger National Park, South Africa. Data were collected from 21 transects first surveyed in April 2006 and resurveyed in November 2008, to determine the relative importance of past damage by these agents on subsequent impacts and mortality. The occurrence of fire or elephant damage in 2006 affected the amount of tree volume subsequently removed by both these agents; elephant removed more tree volume from previously burned trees and the impact of subsequent fire was higher on previously burned or elephant-utilized trees than on undamaged trees. Mortality was also affected by an interaction between previous and recent damage, as the probability of mortality was highest for trees that suffered from fire or elephant utilization after being pushed over. Subsequent fire damage, but not elephant utilization, on debarked trees also increased the probability of mortality. Mortality was twice (4.6% per annum) that of trees progressing into the ≥5 m height class, suggesting an overall decline in large tree density during the 30-month study period. The responses of large trees were species and landscape-specific in terms of sensitivity to elephant and fire impacts, as well as for levels of mortality and progression into the ≥5 m height class. These results emphasize the need for fine-scale site-specific knowledge for effective landscape level understanding of savanna dynamics.     

Spatial Heterogeneity and Soil Nitrogen Dynamics in a Burned Black Spruce Forest Stand: Distinct Controls at Different Scales

We evaluated spatial patterns of soil N and C mineralization, microbial community composition (phospholipid fatty acids), and local site characteristics (plant/forest floor cover, soil pH, soil %C and %N) in a 0.25-ha burned black spruce forest stand in interior Alaska. Results indicated that factors governing soil N and C mineralization varied at two different scales. In situ net N mineralization was autocorrelated with microbial community composition at relatively broad scales (∼ ∼8 m) and with local site characteristics (`site' axis 1 of non-metric scaling ordination) at relatively fine scales (2–4 m). At the scale of the individual core, soil moisture was the best predictor of in situ net N mineralization and laboratory C mineralization, explaining between 47 and 67% of the variation (p < 0.001). Ordination of microbial lipid data showed that bacteria were more common in severely burned microsites, whereas fungi were more common in low fire severity microsites. We conclude that C and N mineralization rates in this burned black spruce stand were related to different variables depending on the scale of analysis, suggesting the importance of considering multiple scales of variability among key drivers of C and N transformations.     

Seasonal Effects on Great Ape Health: A Case Study of Wild Chimpanzees and Western Gorillas

Among factors affecting animal health, environmental influences may directly or indirectly impact host nutritional condition, fecundity, and their degree of parasitism. Our closest relatives, the great apes, are all endangered and particularly sensitive to infectious diseases. Both chimpanzees and western gorillas experience large seasonal variations in fruit availability but only western gorillas accordingly show large changes in their degree of frugivory. The aim of this study is to investigate and compare factors affecting health (through records of clinical signs, urine, and faecal samples) of habituated wild ape populations: a community (N = 46 individuals) of chimpanzees (Pan troglodytes) in Kanyawara, Kibale National Park (Uganda), and a western gorilla (G. gorilla) group (N = 13) in Bai Hokou in the Dzanga-Ndoki National Park (Central African Republic). Ape health monitoring was carried out in the wet and dry seasons (chimpanzees: July–December 2006; gorillas: April–July 2008 and December 2008–February 2009). Compared to chimpanzees, western gorillas were shown to have marginally greater parasite diversity, higher prevalence and intensity of both parasite and urine infections, and lower occurrence of diarrhea and wounds. Parasite infections (prevalence and load), but not abnormal urine parameters, were significantly higher during the dry season of the study period for western gorillas, who thus appeared more affected by the large temporal changes in the environment in comparison to chimpanzees. Infant gorillas were the most susceptible among all the age/sex classes (of both apes) having much more intense infections and urine blood concentrations, again during the dry season. Long term studies are needed to confirm the influence of seasonal factors on health and parasitism of these great apes. However, this study suggest climate change and forest fragmentation leading to potentially larger seasonal fluctuations of the environment may affect patterns of ape parasitism and further exacerbate health impacts on great ape populations that live in highly seasonal habitats.