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Climate refugia can serve as remnant habitat for cold‐adapted species and delay forest transitions. The world's largest freshwater lake by surface area, Lake Superior, serves as a model system for understanding cooling‐mediated refugia effects, as its cool summer water temperatures have maintained disjunct populations of arctic–alpine plants on its shoreline since deglaciation. It is known to affect local inland climates by providing a summer cooling effect; however, the inland temperature gradient and spatial patterns of cooling have not been well quantified. Here, we describe the extent, degree, and patterns of temperature buffering and examine drivers of buffering and disjunct plant occurrence for Lake Superior's north shore over a 3‐year period at distances of 10, 100 m, 1, 10, and 100 km inland. We analyzed temperature data by year, month, summer maximum (July), and growing degree days (GDD0) for each site. Average summertime cooling at shore sites (10 m) was ~5°C cooler than reference sites (100 km inland), with a maximum difference of −19.2°C. The magnitude of cooling varied geographically, with sites further west and southeast showing little to no cooling effect, while the exposed north‐central shore showed the highest degree of buffering (5.8°C cooler) and had a shorter growing season than reference sites. Finally, north‐central shorelines had fewer days above 16°C, a threshold above which disjunct plants are unlikely to grow. These sites also showed the highest proportion of disjunct arctic–alpine species, reflecting the highest buffering from inland sites. On north‐central shores, sites up to 10 km inland had less than 10 days per year warmer than 20°C, a threshold identified for boreal forest transition. An understanding of the extent of lake‐mediated cooling on adjacent forests can better inform the risk to disjunct species, inland forests, and vegetation transition models on Lake Superior's north shore. [ABSTRACT FROM AUTHOR]

Variable retention forest harvesting aims to reduce negative effects of harvesting on forest biodiversity, but knowledge gaps remain regarding its effects on some taxa over longer post-harvest time frames. To better understand effects of variable retention and environmental features on amphibians, we used pitfall traps to capture wood frogs (Lithobates sylvaticus (LeConte, 1825)) across four levels of retention (clearcut (0%), 20%, 50%, and unharvested control (100%)), and two forest types (deciduous and coniferous), in 17-year post-harvest forests in northwest Alberta. We mapped breeding sites and used a LiDAR-based terrain moisture index (depth-to-water) to examine relationships between relative abundance, breeding site proximity, and soil moisture. Retention level alone had no effect on relative abundance of adult wood frogs, but in late summer (July and August), there was a significant interaction between retention level and forest type: capture rates decreased with retention level for deciduous forests, but increased with retention level in conifer forests. During late summer, capture rates were higher in conifer forests than deciduous forests, with soil moisture (lower depth-to-water) positively related to capture rates. Though timber retention may be beneficial to wood frogs in the short term, any impacts of forest harvesting on wood frog abundance were undetectable in stands 17 years post-harvest. [ABSTRACT FROM AUTHOR]

Assessments of large-scale changes in habitat are a priority for management and conservation. Traditional approaches use land use and land cover data (LULC) that focus mostly on "structural" properties of landscapes, rather than "functional" properties related to specific ecological processes. Here, we contend that designing functional analyses of LULC can provide important and complementary information to traditional, structural analyses. We substantiate this perspective with an example of functional changes in habitat due to industrial anthropogenic footprints in Alberta's boreal forest, where there has been little overall forest loss (~ 6% structural change), but high levels of functional change (up to 93% functional change) for species' habitat, biodiversity, and wildfire ignition. We discuss the methods needed to achieve functional LULC analyses, when they are most appropriate to add to structural assessments, and conclude by providing recommendations for analyses of LULC in a future of increasingly high-resolution, dynamic remote sensing data. [ABSTRACT FROM AUTHOR]

The world's forests are highly fragmented by linear disturbances, and many forests have failed to recover decades after abandonment. Lack of recovery is common in unproductive forests, such as treed peatlands, because of conditions that limit tree growth, including simplification of microtopography (loss of microsites). The persistence of these features affects biodiversity, but of particular concern in Canada is the detrimental effects on threatened woodland caribou. Although natural regeneration of trees in peatlands occurs in some places, it is not an effective recovery strategy for restoring the habitat of woodland caribou. This has led to restoration activities with costs exceeding CAD$12 500/km. However, current restoration does not consider wildfires, which can destroy planted trees but also initiate early seral conditions that favor natural regeneration. Here we compared tree regeneration on seismic lines and adjacent forest controls for burnt (75 sites) and unburnt (68 sites) treed peatlands in northeast Alberta, Canada. Tree regeneration (stems with a DBH < 1 cm/ha) varied from 28 500 in burnt lines, 11 440 in unburnt lines, and 18 210 in burnt forest, to 9520 in unburnt forest. Wildfires promoted denser regeneration in sites with a greater proportion of serotinous species and water table depth. Microtopography and terrain wetness explained regeneration on burnt lines, but not unburnt lines. In burnt and unburnt lines, sunlight, microtopography, and depth of water table most affected tree regeneration patterns. [ABSTRACT FROM AUTHOR]

Wildfire is the predominant natural disturbance in the boreal forests of western Canada. Natural disturbance based forest management involves the use of retention harvesting to retain stand structural diversity after harvest; however, unlike fire, this partial harvesting technique does not cause combustion of the forest floor. Application of prescribed burning to areas treated with retention harvesting might emulate the influence of wildfires more effectively than harvesting alone. We compared understory vascular plant diversity, abundance, and composition between forest stands subjected to dispersed retention harvesting (10% retention) with and without prescribed burning 1, 6, and 11 or 12 years after burning. Untreated forest was included as a reference. Research was conducted in conifer-dominated, mixedwood, and deciduous-dominated boreal forest stands in northwestern Alberta, Canada. In deciduous-dominated stands, burned areas of retention harvested stands had higher species richness and greater cover than did unburned areas. In all three forest cover types, effects of harvest with and without burn on species richness, cover, and composition were still evident a decade after disturbance. Fire-adapted species benefited most from the prescribed burn treatment. The combination of prescribed burning with retention harvesting can be considered a useful option in forest management that aims to emulate natural disturbance. [ABSTRACT FROM AUTHOR]

Questions: Are graminoids more poorly detected than other life forms of vascular plants in surveys? How well do observer‐, species‐, and site‐specific variables explain variation in detection of Carex species across forests of different structure? Location: Northeastern Alberta, Canada. Methods: Species inventories were assessed within 50 belt transects, each 100 m in length and 2 m in width. Pseudoturnover was estimated for four life forms and all encountered species. Site‐specific factors were then compared with pseudoturnover of all vascular plants and graminoids using generalized linear regression. Carex detection probabilities were compared based on morphological groups. Detection success at a site and delays in detection within a site were assessed using logistic regression with AIC used to rank a‐priori hypotheses and standardized variables used to determine effect sizes of parameters related to plant detectability. Results: Pseudoturnover for graminoids was similar to that for other life forms and best related to ground layer cover. Morphological groups related to differences in detection, with short, small‐inflorescence Carex most poorly detected. Detection failure was best explained by species abundance and morphology, but delays were more tied to a site's vegetation structure and species abundance than to species morphology. Conclusions: Surveys targeting graminoids, including species of Carex, can achieve high detection rates with high survey effort over small areas, but should consider species‐ and site‐specific biases in detection success. Abundance is likely the most influential factor in determining detection success, and this must be accounted for when searching for low‐density species. We recommend that increased effort (time, repeat observations) be applied when searching for morphologically small graminoids. Imperfect detection is inevitable in surveys, and the degree to which this causes bias against certain taxa is unclear. Graminoids were not more overlooked than other life‐forms, but detectability varies within this group. Abundance and species morphology were the most important determinants of detection success among Carex. Our study showed clear bias toward short, small‐inflorescence Carex, even given high survey effort. [ABSTRACT FROM AUTHOR]

Alberta, Canada's grizzly bears remain a threatened species, with ongoing controversy limiting achievements. Using a social constructionist approach, together with wildlife value orientations and attitudes descriptions within social process mapping, we explored what grizzly bears and recovery mean to people. Semi-structured interviews revealed unique sub-groups, including Homesteader, Frontiersmen, Exurbans, and government Biologists and Officers, whose values are reflective of their identity. While utilitarian or mutualistic orientations were helpful, uncovering identity in relation to values, as part of historical socio-cultural conditions and policy processes, illustrated the importance of power in grizzly bear governance. Our findings suggest collaborative policy processes should be established, to build understanding, relations of trust, and identify common ground to benefit people and bears. Broadly, we suggest researchers look to utilizing qualitative approaches, as well as social constructionism and social process mapping, to better understand and articulate the importance of social-cultural conditions and processes in conservation policy. [ABSTRACT FROM AUTHOR]

Seismic lines are linear features created by the oil and gas industry for energy exploration. Though individually narrow, collectively seismic lines are a pervasive management challenge, resulting in changes to biogeochemical cycles, plant and animal abundance and behaviour, predator–prey relationships, and forest successional trajectories. These impacts arise from historical construction methods that used bulldozers to remove vegetation and substrate leaving lines as persistent openings in a state of arrested succession. In the mid-1990s, "low-impact seismic" (LIS) line construction began, using mulchers to remove vegetation aboveground to minimize impacts and hasten reforestation. Here, we evaluated the effectiveness of LIS in retention, recruitment, and growth of seedlings in forested peatlands in northeast British Columbia. Retained and recruited trees on LIS lines were found at 69% and 64% of sites, had mean densities of 3400 and 6000 stems/ha, and mean heights of 42 and 11 cm, respectively. These LIS lines appeared to recover along expected trajectories toward tree cover, thereby mitigating challenges typical of older seismic exploration. Our results suggest it is feasible to further fast-forward line recovery by ensuring mulcher drums are kept as high as possible to increase the number and height of trees through the mulching process. [ABSTRACT FROM AUTHOR]

A major unresolved question for omnivorous carnivores, like most species of bears, is to what degree are populations influenced by bottom-up (food supply) or top-down (human-caused mortality) processes. Most previous work on bear populations has focused on factors that limit survival (top-down) assuming little effect of food resource supply. When food resources are considered, most often they consider only the availability/supply of a single resource, particularly marine-subsidized or terrestrial sources of protein (carnivory) or alternately hard or soft mast (frugivory). Little has been done to compare the importance of each of these factors for omnivorous bears or test whether complementary resources better explain individual animal and population measures such as density, vital rates, and body size. We compared landscape patterns of digestible energy (kcal) for buffaloberry (a key source of carbohydrate) and ungulate matter (a key source of protein and lipid) to local measures in grizzly bear Ursus arctos abundance at DNA hair snag sites in west-central Alberta, Canada. We tested support for bottom-up hypotheses in either single (carnivory [meat] versus frugivory [fruit]) or complementary (additive or multiplicative) food resources, while accounting for a well-known top-down limiting factor affecting bear survival (road density). We found support for both top-down and bottom-up factors with complementary resources (co-limitation) supported over single resource supplies of either meat or fruit. Our study suggests that the availability of food resources that provide complementary nutrients is more important in predicting local bear abundance than single foods or nutrients (e.g. protein) or simply energy per se. This suggests a nutritionally multidimensional bottom-up limitation for a low density interior population of grizzly bears. [ABSTRACT FROM AUTHOR]

Climate and land-use change are expected to substantially alter future plant species distributions leading to higher extinction rates. However, little is known about how plant species ranges, richness and phylogenetic diversity of continents will be affected by these dynamics., We address this gap here by examining the patterns of species' distributions and phylogenetic relationships for 7465 seed plant taxa in North America. An ensemble of species distribution models was used to estimate the potential suitable habitat of species under different sets of climate, land-use and dispersal constraint scenarios. We then evaluated the vulnerability and extinction risk of individual species to changes in climate and land use, and examined whether rare, endangered and evolutionarily distinct species were disproportionally threatened by climate and land-use change., We show that ~2000 species may lose >80% of their suitable habitats under the A1b emission scenario for the 2080s, while ~100 species may experience >80% range expansions (a 20 : 1 ratio of loss to gain). When considering >50% range retraction and expansion, the ratio of loss to gain was 13 : 1. A greater loss of species diversity is expected at low latitudes, while larger gains are expected at high latitudes. Evolutionarily distinct species are predicted to have significantly higher extinction risks than extant species. This suggests a disproportionate future loss of phylogenetic diversity for the North American flora., Synthesis and applications. Our study provides continental-scale evidence of plant species extinction risk caused by future climate and land-use change, and highlights the importance of integrating phylogenetic measures into conservation risk assessments. This work provides insight into the status, trends and threats for a large share of North America's plant species by identifying risks and prioritizing conservation in a rapidly changing world. [ABSTRACT FROM AUTHOR]

Canopy height is a key factor that affects carbon storage, vegetation productivity and biodiversity in forests, as well as an indicator of key processes such as biomass allocation. However, global variation in forest canopy height and its determinants are poorly known., We used global data on Light Detection and Ranging-derived maximum forest canopy height ( Hmax) to test hypotheses relating Hmax to current climate (water availability, ambient energy and water-energy dynamics), regional evolutionary and biogeographic history, historical climate change, and human disturbance., We derived Hmax for 32 304 forested 55-km grid cells using 1-km global canopy height data (maximum height of 1-km cells within a 55-km grid). Variation in Hmax was related to latitude and biomes, along with environmental and historical variables. Both spatial and non-spatial linear models were used to assess the relative importance of the different hypothesized factors., Hmax was inversely related to latitude (i.e. tall canopies at the equator), but with high geographical variability. Actual evapotranspiration and annual precipitation were the factors most correlated to Hmax globally, thus supporting the water-energy dynamics hypothesis. However, water limitation emerged as a key factor in tropical and temperate biomes within specific geographic regions, while energy limitation was a more important factor in boreal regions where temperature is more limiting to trees than water., Hmax exhibited strong variation among biogeographic regions, supporting the role of regional evolutionary and biogeographic history in structuring broad-scale patterns in canopy height. Furthermore, there were divergent relationships between climate and Hmax between the Southern and Northern Hemispheres, consistent with historical evolutionary contingencies modulating these relationships. Historical climate change was also related to Hmax, albeit not as strongly, with shorter canopy heights where late-Quaternary climate has been less stable. In contrast, human disturbance was only weakly related to Hmax at the scale (55 km) examined here., Synthesis. This study confirms that forest canopy height is strongly controlled by current climate, but also provides evidence for an important supplementary role for regional-historical factors. This highlights the importance of considering evolutionary and biogeographic history for achieving a comprehensive understanding of forest ecosystem properties. [ABSTRACT FROM AUTHOR]

Aim Forecasting potential patterns in species' distributions and diversity under climate change is crucial for biodiversity conservation. Although high-latitude regions are expected to experience some of the greatest increases in temperature due to global warming, little is known on how individual responses in species will affect patterns in phylogenetic diversity (PD). Location Alberta, Canada. Methods We used 160,589 occurrence records for 1541 species of seed plants in Alberta (nearly 90% of the province's seed flora) and ensemble niche models to project current and future suitable habitats. We then examined climate change vulnerability of individual species and the potential impacts of climate change on species richness, PD and both taxonomic and phylogenetic endemism (PE). We also assessed whether predicted losses of PD were distributed randomly across the plant tree of life. Results We found that 368 species (24%) may lose on average > 80% of their current suitable climates (habitats), while 539 species (35%) were projected to more than double their current suitable range. Both species richness and PD were predicted to increase in most areas, except for the species-rich Rocky Mountains, which are predicted to experience future declines. Maps of taxonomic and PE identified several regions with high conservation value and climate change threat suggesting priorities for conservation and climate change adaptation. Overall, a non-random extinction risk was found for Alberta's flora, demonstrating potential future impacts of climate change on the loss of evolutionary history. Main conclusions Our analyses suggest that climate change will have asymmetrical effects on the distribution of Alberta's plant diversity and endemism and a non-random extinction risk of the current state of species evolutionary history. Our results provide practical guidance for biodiversity conservation and management in this region by prioritizing species' vulnerabilities and places with higher taxonomic or evolutionary risk due to future climate change. [ABSTRACT FROM AUTHOR]

ABSTRACT Understanding species habitat selection and factors that drive selection are key components for conservation. We report the first resource selection functions (RSFs) for bison inhabiting an arid ecosystem and use them with density estimates of bison to estimate the number of bison that could be supported if the bison range were expanded to federal lands in the San Luis Valley of Colorado. We derived RSFs for vegetation types using locations of plains bison collected weekly over 3 years from 2005 to 2007. Bison selected for wet or mesic grassland habitats in all seasons. Wetland selection by bison was predicted to be 18 times greater than that of rabbitbrush vegetation, the reference category, and selection of meadows was predicted to be 11 times greater than that of the rabbitbrush type. Willow-dominated plant communities were strongly avoided. Cottonwood communities were also avoided, with the exception of some moderate levels of selection in fall. The willow and cottonwood communities have an understory with low biomass of herbaceous species and low productivity in this arid system. Based on the RSFs we predicted that in the San Luis Valley of Colorado up to 2,379 bison could be supported in similar habitats under Fish and Wildlife Service (FWS) jurisdiction, and up to 759 bison could be supported on adjacent National Park Service (NPS) land. This modeling framework provides a conservation tool for the restoration of bison to their historical habitats, and has utility for application to other terrestrial species where assumptions are met. Published 2015. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

As the influence of human activities on natural systems continues to expand, there is a growing need to prioritize not only pristine sites for protection, but also degraded sites for restoration. We present an approach for simultaneously prioritizing sites for protection and restoration that considers landscape patterns for a threatened population of grizzly bears (Ursus arctos) in southwestern Alberta, Canada. We considered tradeoffs between bottom-up (food resource supply) and top-down (mortality risk from roads) factors affecting seasonal habitat quality for bears. Simulated annealing was used to prioritize source-like sites (high habitat productivity, low mortality risk) for protection, as well as sink-like sites (high habitat productivity, high mortality risk) for restoration. Priority source-like habitats identified key conservation areas where future developments should be limited, whereas priority sink-like habitats identified key areas for mitigating road-related mortality risk with access management. Systematic conservation planning methods can be used to complement traditional habitat-based methods for individual focal species by identifying habitats where conservation actions (both protection and restoration) have the highest potential utility. [ABSTRACT FROM AUTHOR]

ABSTRACT Fragmentation is a growing threat to wildlife worldwide and managers need solutions to reverse its impacts on species' populations. Populations of grizzly bears ( Ursus arctos), often considered an umbrella and focal species for large mammal conservation, are fragmented by human settlement and major highways in the trans-border region of southern British Columbia, northern Montana, Idaho, and northeastern Washington. To improve prospects for bear movement among 5 small fragmented grizzly bear subpopulations, we asked 2 inter-related questions: Are there preferred linkage habitats for grizzly bears across settled valleys with major highways in the fragmented trans-border region, and if so, could we predict them using a combination of resource selection functions and human settlement patterns? We estimated a resource selection function (RSF) to identify high quality backcountry core habitat and to predict front-country linkage areas using global positioning system (GPS) telemetry locations representing an average of 12 relocations per day from 27 grizzly bears (13F, 14M). We used RSF models and data on human presence (building density) to inform cost surfaces for connectivity network analyses identifying linkage areas based on least-cost path, corridor, and circuit theory methods. We identified 60 trans-border (Canada-USA) linkage areas across all major highways and settlement zones in the Purcell, Selkirk, and Cabinet Mountains encompassing 24% of total highway length. We tested the correspondence of the core and linkage areas predicted from models with grizzly bear use based on bear GPS telemetry locations and movement data. Highway crossings were relatively rare; however, 88% of 122 crossings from 13 of our bears were within predicted linkage areas (mean = 8.3 crossings/bear, SE = 2.8, range 1-31, 3 bears with 1 crossing) indicating bears use linkage habitat that could be predicted with an RSF. Long-term persistence of small fragmented grizzly bear populations will require management of connectivity with larger populations. Linkage areas identified here could inform such efforts. © 2015 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Aim Presence-only datasets represent an important source of information on species' distributions. Collections of presence-only data, however, are often spatially biased, particularly along roads and near urban populations. These biases can lead to inaccurate inferences and predicted distributions. We demonstrate a new approach of accounting for effort bias in presence-only data by explicitly incorporating sample biases in species distribution modelling. Location Alberta, Canada. Methods First, we used logistic regression to model sampling effort of recorded rare vascular plants, bryophytes and butterflies in Alberta. Second, we simulated presence/absence data for nine 'virtual' species based on three relative occurrence thresholds - common, rare and very rare - for each taxonomic group. We sampled these virtual species using our bias model to represent typical sampling effort characteristic of presence-only datasets. We then modelled the distributions of these virtual species using logistic regression and attempted to recover their original simulated distributions using a sample weighting term (prior weight) estimated as the inverse of probability of sampling. Bias-adjusted model estimates were compared to those obtained from random samples and biased samples without adjustment. We also compared prior-weight adjustment to bias-file and target-group background approaches in Maxent. Results Sample weighting recovered regression coefficients and mapped predictions estimated from unbiased presence-only data and improved model predictive accuracy as evaluated by regression and correlation coefficients, sensitivity and specificity. Similar model improvements were achieved using the Maxent bias-file method, but results were inconsistent for the target-group background approach. Main conclusions These results suggest that sample weighting can be used to account for spatially biased presence-only datasets in species distribution modelling. The framework presented is potentially widely applicable due to availability of online biodiversity databases and the flexibility of the approach. [ABSTRACT FROM AUTHOR]

Mapping of oil reserves involves the use of seismic lines (linear disturbances) to determine both their location and extent. Conventional clearing techniques for seismic assessment have left a legacy of linear disturbances that cause habitat fragmentation. Little is known, however, about how local and landscape factors affect natural regeneration patterns of trees and shrubs on seismic lines that facilitate mapping and future projections of regeneration patterns. To understand factors affecting early forest regeneration and to predict future trends in regeneration of legacy seismic lines we used LiDAR, forest stand databases and a disturbance inventory of conventional seismic lines to model seismic line regeneration to a 3 m height in a 1806 km 2 area in northeastern Alberta, Canada. Regeneration to 3 m was inversely related to terrain wetness, line width, proximity to roads (as a proxy for human use of lines), and the lowland ecosites. Overall, terrain wetness and the presence of fen ecosites had the strongest negative effect on regeneration patterns; the wettest sites failed to recover even after 50 years post-disturbance. Predictions of future regeneration rates on existing lines suggested that approximately one-third of existing linear disturbance footprints in this boreal landscape will remain un-regenerated 50 years later resulting in persistent habitat fragmentation. Model predictions estimating regeneration probability are particularly valuable for estimating current and future forest regeneration trajectories on linear disturbances which are a conservation concern and a focus for restoration and planning by government, industry and conservation organizations. [ABSTRACT FROM AUTHOR]

A significant challenge to monitoring wildlife that are secretive, wide ranging, and at low densities is the need to achieve adequate detection rates. Knowledge of spatial patterns in occupancy and the spatial and/or temporal patterns in detectability allows for stratification of traps and improved detection rates. This study investigated how local variation in habitats affected the detectability of grizzly bears in west-central Alberta when monitored with a fixed DNA hair snag design. Bear hair samples were collected in 2011 at 60 sites across 1500 km2 over six sessions, each 14 days in length, between June and August. Microsatellite analysis of hair samples revealed grizzly bear detections at 25 of 60 sites and 21 individual bears. We investigated occupancy and detectability of grizzly bears at the patch and landscape scales using detection histories and program PRESENCE. At the patch scale, grizzly bear detection was highest when sites were placed near streams with clover and in intermediate levels of forest crown closure. At the landscape scale, probability of detection increased near streams and oil and gas wellsites, especially when food resources and wellsite density in the surrounding area was low. Our results highlight the importance of considering local food resources and habitat conditions during placement of fixed DNA hair snag sites. Detectability was not found to vary over time, suggesting that sampling in west-central Alberta can occur at any time between June and August. [ABSTRACT FROM AUTHOR]

Treed peatlands are dominated by bryophytes, particularly Sphagnum spp., which create the characteristic hummock‐hollow microtopography. This, in turn, shapes the distribution of bryophyte communities. Disturbances can lead to a loss of this microtopographic variation, impacting the bryophyte community. Seismic lines are deforested linear disturbances (approximately 3–8 m wide) created during oil and gas exploration and very extensive in Alberta, Canada. Loss of microtopographic variation leads to slow tree recovery on seismic lines in treed peatlands. To facilitate tree establishment, mounding is being applied to restore the microtopography on seismic lines. We compared bryophyte communities on unmounded and mounded seismic lines (18 years after seismic line creation, 3 years after mounding), and in adjacent treed fens as the reference, to evaluate how recovery varies with microtopographic position (i.e., top of hummock, slope or side of the hummock, and level ground). We found that recovery on the unmounded seismic lines was underway 18 years after seismic lines were created, while mounding redisturbed the sites and thus set back recovery, at least in the short term (3 years post‐mounding). In unmounded seismic lines, Sphagnum cover was similar to that of reference treatments at all microtopographic positions. In contrast, mounded seismic lines had lower Sphagnum cover and higher cover of true mosses (sans feather mosses) than reference and unmounded treatments. Overall, these results show mounding sets back the recovery of bryophyte communities—the very organisms responsible for the microtopographic variation we are trying to establish. Further monitoring is needed to understand how this changes over time. [ABSTRACT FROM AUTHOR]

Hibernation is an adaptive strategy to avoid harsh environmental conditions and seasonal limitations in food and water. Unlike most hibernators, grizzly bears ( Ursus arctos) are aroused easily while in dens and disturbances while denning can result in fitness costs if bears become active during this period. Our objectives were to determine den selection of male and female grizzly bears at multiple spatial scales in the boreal forest and Rocky Mountains of Alberta, Canada. Grizzly bears in Alberta are designated as threatened. However, little is known about den selection by grizzly bears in the boreal forest and the current land and forest management plans do not include any mitigation measures to minimize possible impacts on the denning habitat of grizzly bears. We compared dens to random available locations within fall home ranges using geographic information system-derived anthropogenic, land cover, landscape, and food resource variables. Male and female grizzly bears had similar habitat requirements when selecting dens, and females did not avoid sites associated with a greater probability of encountering males. At the broadest scale investigated, grizzly bears avoided wetlands, and selected high-elevation, dry conifer stands with abundant high-quality spring food. At more localized scales, grizzly bears selected areas of low road densities and dense conifers associated with little high-quality autumn food. Slope angle had the most influence on den selection followed by percent autumn food, road densities, percent wetland, and percent spring food. We recommend limiting human disturbance, including open roads, within core grizzly bear conservation areas for areas with high suitable den habitat. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Numerous factors influence fitness of free-ranging animals, yet often these are uncharacterized. We integrated GPS habitat use data and genetic profiling to determine their influence on fitness proxies (mass, length, and body condition) in a threatened population of grizzly bears (Ursus arctos) in Alberta, Canada. We detected distinct genetic and habitat use (ecotype) clusters, with individual cluster assignments, or genotype/ecotype, being correlated (Pearson r = 0.34, P < 0.01). Related individuals showed evidence of similar habitat use patterns, irrespective of geographic distance and sex. Fitness proxies were influenced by sex, age, and habitat use, and homozygosity had a positive effect on these proxies that could be indicative of outbreeding depression. We further documented over 300 translocations occurring in the province since the 1970s, often to areas with significantly different habitat. We argue this could be unintentionally causing the pattern of outbreeding, although the heterozygosity correlation may instead be explained by the energetic costs associated with larger body size. The observed patterns, together with the unprecedented human-mediated migrations, make understanding the link between genotype, ecotype, and phenotype and mechanisms behind the negative heterozygosity-fitness correlations critical for management and conservation of this species. [ABSTRACT FROM AUTHOR]

Habitat selection is an important behavioural process widely studied for its population-level effects. Models of habitat selection are, however, often fit without a mechanistic consideration. Here, we investigated whether patterns in habitat selection result from instinct or learning for a population of grizzly bears (Ursus arctos) in Alberta, Canada. We found that habitat selection and relatedness were positively correlated in female bears during the fall season, with a trend in the spring, but not during any season for males. This suggests that habitat selection is a learned behaviour because males do not participate in parental care: a genetically predetermined behaviour (instinct) would have resulted in habitat selection and relatedness correlations for both sexes. Geographic distance and home range overlap among animals did not alter correlations indicating that dispersal and spatial autocorrelation had little effect on the observed trends. These results suggest that habitat selection in grizzly bears are partly learned from their mothers, which could have implications for the translocation of wildlife to novel environments. [ABSTRACT FROM AUTHOR]

Abstract: Most current wildlife habitat models, such as resource selection functions, typically assume a static environment, extrapolate poorly in space and time, and often lack linkages to population processes. We submit that more mechanistic habitat models that directly consider bottom-up resources affecting growth and reproduction (i.e., food) and top-down limitations affecting survival are needed to effectively predict habitat quality, especially in the presence of rapid environmental change. Here we present a general model for estimating potential habitat quality (relating to growth and reproduction) and realised habitat quality (accounting for survival) using basic knowledge of the species’ seasonal diet, predicted locations of food resource patches and regional patterns in mortality risk. We illustrate our model for a threatened population of grizzly bears in west-central Alberta. Bi-monthly potential habitat quality successfully predicted habitat selection by radio-collared grizzly bears, while multi-seasonal realised habitat quality predicted patterns in occupancy-abundance as measured from unique bears at hair-snag sites. Bottom-up resources therefore predicted patterns of habitat selection, while top-down processes (survival) were necessary to scale-up to population measures. We suggest that more direct measures of resources and environments that affect growth, reproduction and survival, as well as match the temporal scale of animal behaviour, be considered when developing wildlife habitat models. [Copyright &y& Elsevier]

Aim Greater sage-grouse ( Centrocercus urophasianus), a shrub-steppe obligate species of western North America, currently occupies only half its historical range. Here we examine how broad-scale, long-term trends in landscape condition have affected range contraction. Location Sagebrush biome of the western USA. Methods Logistic regression was used to assess persistence and extirpation of greater sage-grouse range based on landscape conditions measured by human population (density and population change), vegetation (percentage of sagebrush habitat), roads (density of and distance to roads), agriculture (cropland, farmland and cattle density), climate (number of severe and extreme droughts) and range periphery. Model predictions were used to identify areas where future extirpations can be expected, while also explaining possible causes of past extirpations. Results Greater sage-grouse persistence and extirpation were significantly related to sagebrush habitat, cultivated cropland, human population density in 1950, prevalence of severe droughts and historical range periphery. Extirpation of sage-grouse was most likely in areas having at least four persons per square kilometre in 1950, 25% cultivated cropland in 2002 or the presence of three or more severe droughts per decade. In contrast, persistence of sage-grouse was expected when at least 30 km from historical range edge and in habitats containing at least 25% sagebrush cover within 30 km. Extirpation was most often explained (35%) by the combined effects of peripherality (within 30 km of range edge) and lack of sagebrush cover (less than 25% within 30 km). Based on patterns of prior extirpation and model predictions, we predict that 29% of remaining range may be at risk. Main Conclusions Spatial patterns in greater sage-grouse range contraction can be explained by widely available landscape variables that describe patterns of remaining sagebrush habitat and loss due to cultivation, climatic trends, human population growth and peripherality of populations. However, future range loss may relate less to historical mechanisms and more to recent changes in land use and habitat condition, including energy developments and invasions by non-native species such as cheatgrass ( Bromus tectorum) and West Nile virus. In conjunction with local measures of population performance, landscape-scale predictions of future range loss may be useful for prioritizing management and protection. Our results suggest that initial conservation efforts should focus on maintaining large expanses of sagebrush habitat, enhancing quality of existing habitats, and increasing habitat connectivity. [ABSTRACT FROM AUTHOR]

Forest managers are increasingly considering historic patterns of natural forest disturbance as a model for forest harvesting and as a coarse-filter ecosystem management tool. We evaluated the long-term (100-year) persistence of a grizzly bear population in Alberta, Canada using forest simulations and habitat modelling. Even with harvesting the same volume of timber, natural disturbance-based forestry resulted in a larger human footprint than traditional two-pass forestry with road densities reaching 1.39km/km2 or more than three times baseline conditions and suggested maximum levels of security for grizzly bears. Because bears favour young forests and edges where food resources are plentiful, a future shift to young forests and more edge habitat resulted in a 20% projected increase in habitat quality and a 10% projected increase in potential carrying capacity. Human-caused mortality risk, however, offset any projected gains in habitat and carrying capacity resulting in the loss of all secure, unprotected territories, regardless of forest harvest method, within the first 20–30 years of simulation. We suggest that natural disturbance-based forestry is an ill-suited management tool for sustaining declining populations of grizzly bears. A management model that explicitly considers road access is more likely to improve grizzly bear population persistence than changing the size of clear-cuts. In fact, large clear cuts might be counter productive for bears since a diversity of habitats within each bear’s home range is more likely to buffer against future uncertainties. [Copyright &y& Elsevier]

Applications of logistic regression in a used-unused design in wildlife habitat studies often suffer from asymmetry of errors: used resource units (landscape locations) are known with certainty, whereas unused resource units might be observed to be used with greater sampling intensity. More appropriate might be to use logistic regression to estimate a resource selection function (RSF) tied to a use-availability design based on independent samples drawn from used and available resource units. We review the theoretical motivation for RSFs and show that sample "contamination" and the exponential form commonly assumed for the RSF are not concerns, contrary to recent statements by Keating and Cherry (2004; Use and interpretation of logistic regression in habitat-selection studies. Journal of Wildlife Management 68:774-789). To do this, we re-derive the use-availability likelihood and show that it can be maximized by logistic regression software. We then consider 2 case studies that illustrate our findings. For our first case study, we fit both RSFs and resource selection probability functions (RSPF) to point count data for 4 bird species with varying levels of occurrence among sample blocks. Drawing on our new derivation of the likelihood, we sample available resource units with replacement and assume overlapping distributions of used and available resource units. Irrespective of overlap, we observed approximate proportionality between predictions of a RSF and RSPF. For our second case study, we evaluate the classic use-availability design suggested by Manly et al. (2002), where availability is sampled without replacement, and we systematically introduce contamination to a sample of available units applied to RSFs for woodland caribou (Rangifer tarandus caribou). Although contamination appeared to reduce the magnitude of one RSF beta coefficient, change in magnitude exceeded sampling variation only when >20% of the available units were confirmed caribou use locations (i.e., contaminated). These empirically based simulations suggest that previously recommended sampling designs are robust to contamination. We conclude with a new validation method for evaluating predictive performance of a RSF and for assessing ff the model deviates from being proportional to the probability of use of a resource unit. [ABSTRACT FROM AUTHOR]

Understanding patterns of species occurrence and abundance is a central theme of ecology, natural resource management, and conservation. Although occurrence models have been widely used for describing species distribution, particularly for rare species, abundance models are less common, despite greater information for conservation and management. Because presence-absence data are easier and less expensive to collect, predictions of abundance from patterns of occurrence could prove useful. We examined the relationship between occurrence and abundance for two species with very different life histories: bracken fernPteridium aquilinumand mooseAlces alces. We predicted that if occurrence and abundance were functionally related we should observe: 1) correlation between predicted probability of occurrence and observed abundance; 2) similar environmental covariates and estimated coefficients for occurrence models developed separately for low-density, high-density, and global data sites; and 3) parallel coefficients for the occurrence and abundance components of zero-inflated count models. Probability of occurrence was not correlated with abundance-when-present for bracken fern, while evidence for a relationship for moose was apparent at densities of animals below 7 individuals per cutblock. Coefficients for models at different levels of density did not vary significantly. However, once occurrence was accounted for, measured environmental data appeared less important in describing abundance. For bracken, covariates of zero-inflated count models differed in their expression of occurrence and abundance. Differences were less extreme for moose; however, results from the two-process models suggest that distribution and abundance may be a function of different processes. Environmental factors influencing abundance may differ from those limiting distribution. Life history, scale, site history, and socio-competitive processes further help shape patterns of abundance. Two-stage modeling provides a powerful tool for describing animal and plant distribution where the processes of occurrence and abundance are influenced by different factors. [ABSTRACT FROM AUTHOR]

We examined the spatial patterns of 297 human-caused grizzly bear mortalities from 1971 to 2002 within the Central Rockies ecosystem (CRE) of Canada to explore relationships between mortalities and variables reflecting human development, terrain, and vegetation. Using logistic regression, we modelled the distribution of grizzly bear mortalities based on local landscape attributes as well as examining variation among demographic status, seasons, and mortality type. Grizzly bear mortalities were concentrated in three main regions of the CRE: (1) Lake Louise; (2) Banff town site; and (3) Alberta Provincial lands near the Red Deer River. We found no evidence for environmental differences in mortality locations between sexes or seasons, while sub-adult male and legal harvest mortalities were more dispersed than other mortalities. Models describing the relative risk of mortality were positively associated with human access, water, and edge features, while negatively associated with terrain ruggedness and greenness indices. Model predictions fit well with independent data. Overall, relatively little of the landscape was secure from human-caused mortality for grizzly bears. This would be most directly remedied by controlling human access. [Copyright &y& Elsevier]

Journal of Applied Ecology (2004) 41, 201–212 [ABSTRACT FROM AUTHOR]

Climate change refugia are areas that are relatively buffered from contemporary climate change and may be important safe havens for wildlife and plants under anthropogenic climate change. Topographic variation is an important driver of thermal heterogeneity, but it is limited in relatively flat landscapes, such as the boreal plain and prairie regions of western Canada. Topographic variation within this region is mostly restricted to river valleys and hill systems, and their effects on local climates are not well documented. We sought to quantify thermal heterogeneity as a function of topography and vegetation cover within major valleys and hill systems across the boreal–grassland transition zone. Using iButton data loggers, we monitored local temperature at four hills and 12 river valley systems that comprised a wide range of habitats and ecosystems in Alberta, Canada (N = 240), between 2014 and 2020. We then modeled monthly temperature by season as a function of topography and different vegetation cover types using general linear mixed effect models. Summer maximum temperatures (Tmax) varied nearly 6°C across the elevation gradient sampled. Local summer mean (Tmean) and maximum (Tmax) temperatures on steep, north‐facing slopes (i.e., low levels of potential solar radiation) were up to 0.70°C and 2.90°C cooler than highly exposed areas, respectively. Tmax in incised valleys was between 0.26 and 0.28°C cooler than other landforms, whereas areas with greater terrain roughness experienced maximum temperatures that were up to 1.62°C cooler. We also found that forest cover buffered temperatures locally, with coniferous and mixedwood forests decreasing summer Tmean from 0.23 to 0.72°C and increasing winter Tmin by up to 2°C, relative to non‐forested areas. Spatial predictions of temperatures from iButton data loggers were similar to a gridded climate product (ClimateNA), but the difference between them increased with potential solar radiation, vegetation cover, and terrain roughness. Species that can track their climate niche may be able to compensate for regional climate warming through local migrations to cooler microsites. Topographic and vegetation characteristics that are related to cooler local climates should be considered in the evaluation of future climate change impacts and to identify potential refugia from climate change. [ABSTRACT FROM AUTHOR]

Questions: Edge influence on forest biodiversity is an important environmental effect associated with habitat fragmentation, but extrapolating the influence of edges across the broader landscape has been difficult, especially for situations where multiple edges exist in close proximity. We asked whether there were differences in edge effects between two types (3 m vs 8 m width) of low‐severity linear disturbance (seismic lines) and whether there were interactions of edge effects when seismic lines occur in dense networks; that is, do multiple narrow seismic lines have a stronger or weaker edge influence than a single narrow seismic line. Location: Treed peatlands in northeastern Alberta, Canada. Methods: Seismic lines are created during oil and gas exploration and are responsible for dissection of boreal forests in western Canada. We sampled vascular plants along transects perpendicular to seismic lines in moderate‐rich and poor treed fens. We used the "Randomization Test of Edge Influence" (RTEI) to calculate the magnitude and distance of edge effects and then compared these between narrower (3 m) versus wider (8 m) lines and between single narrow lines versus multiple narrow lines (parallel and ~50 m apart). Results: In moderate‐rich fens, we found a positive edge influence on understorey diversity from both wide and narrow seismic lines. We also found a weakening edge interaction on diversity, that is, single narrow seismic lines had a stronger edge influence on diversity than did multiple narrow seismic lines. In treed poor fens, multiple narrow seismic lines had a negative edge effect on tree density, understorey abundance, richness, and composition. In addition, we found strengthening edge interactions in treed poor fens on tree density, graminoid cover, and understorey composition. Conclusions: Even narrow linear disturbances, such as seismic lines, can have significant edge effects and these are exacerbated when lines occur in dense networks. [ABSTRACT FROM AUTHOR]

This study assessed the reproductive success of a temperate dioecious shrub, Canada buffaloberry, Shepherdia canadensis (L.) Nutt., in central Alberta, Canada, by examining the effects of spatial patterns and overstory canopy on flower and fruit production. S. canadensis is more abundant and productive (more fruit) at forest edges and in forest gaps, suggesting a dependence on higher light conditions than is typical of late-seral forests. We used path analysis to demonstrate that flower and fruit production exhibited density-dependent effects at a scale of 50 m2 around focal female plants. Fruit production was positively affected by male intraspecific density (pollen supply) and negatively affected by female intraspecific density (pollen competition), but not correlated with overall intraspecific density. The effects of sex-differentiated density are partly due to pollinator responses to male plant density. Flower production was positively affected by overall intraspecific density. A pollen supplementation trial doubled fruit production relative to a control, demonstrating that local male density (pollen availability) and pollinator activity can limit fruit production in S. canadensis. Canopy cover was negatively related to both flower and total fruit production, with approximately one-third (34%) of the total effect of canopy on fruit production due to the effect of canopy on flower production. The commonly observed negative association between canopy cover and fruit production in buffaloberry, therefore, is partly a result of the reduction first in flower number and second in fruit set. This study clarifies the mechanisms associated with the often-noted observation, but not previously assessed at the level of individuals, that reproductive output in S. canadensis is density dependent, limited by canopy cover through reductions in both flowering and fruit set, and pollinator limited. These findings hold implications for managing animal species that depend on the fruit of S. canadensis and suggest future directions for research on dioecious and actinorhizal species. [ABSTRACT FROM AUTHOR]

Diet is one of the most common traits used to organize species of animals into niches. For ruminant herbivores, the breadth and uniqueness of their dietary niche are placed on a spectrum from browsers that consume woody (i.e., browse) and herbaceous (i.e., forbs) plants, to grazers with graminoid-rich diets. However, seasonal changes in plant availability and quality can lead to switching of their dietary niche, even within species. In this study, we examined whether a population of wood bison (Bison bison athabascae) in northeast Alberta, Canada, seasonally switched their foraging behavior, and if so, whether this was associated with changes in nutrient acquisition. We hypothesized that bison should switch foraging behaviors from grazing in the winter when standing, dead graminoids are the only foliar plants readily available to browsing during spring and summer as nutritious and digestible foliar parts of browse and forbs become available. If bison are switching foraging strategy to maximize protein consumption, then there should be a corresponding shift in the nutritional niche. Alternatively, if bison are eating different plants, but consuming similar amounts of nutrients, then bison are switching their dietary niche to maintain a particular nutrient composition. We found wood bison were grazers in the winter and spring, but switch to a browsing during summer. However, only winter nutrient consumption of consumed plants differed significantly among seasons. Between spring and summer, bison maintained a specific nutritional composition in their diet despite compositional differences in the consumed plants. Our evidence suggests that bison are selecting plants to maintain a target macronutrient composition. We posit that herbivore's can and will switch their dietary niche to maintain a target nutrient composition. [ABSTRACT FROM AUTHOR]

Seismic lines in western Canada's boreal region are linear disturbances that affect the habitat of threatened woodland caribou (Rangifer tarandus caribou). To hasten the return of forest cover and ultimately to restore caribou habitat, restoration managers use silviculture treatments in wet areas that involve the mechanical mounding of seismic lines to create artificial hummocks. Tree planting then takes place on top of these hummocks. However, the effectiveness of this silviculture technique for restoring seismic lines in peatlands is largely untested. Here we sampled incremental height growth of coniferous seedlings at 41 seismic line plots in poor and rich treed fens in northeast Alberta, Canada. We compared lines that had been treated with inverted mounding (a type of mechanical mounding) and subsequent tree planting, to nearby lines that were left untreated for natural recovery. We used generalized linear mixed models to test the effect of silviculture treatments on 5‐year growth increments of black spruce (Picea mariana) and tamarack (Larix laricina). Overall, we found that mounding and tree planting improved seedling growth compared to seismic lines regenerating naturally. However, growth responses were found to vary by species, ecosite, initial seedling size, and light availability. This suggests that site‐specific prioritization of mounding within peatlands may be more efficient considering the widespread nature of seismic lines. Future experiments testing growth responses to other mounding techniques that are designed to preserve the soil profile. It is also important for managers to weigh restoration goals beyond tree establishment and an accelerated return to forest cover. [ABSTRACT FROM AUTHOR]

In ecological niche theory, diet is a trait frequently used to place species along a continuum from specialists to generalists. A multidimensional approach to investigating species' niches has been developed to incorporate nutrition. We apply the concepts of multidimensional nutritional niche theory to the dietary patterns of a widespread, large herbivore, the American bison Bison bison, at various levels of its nutritional niche.Specifically, we sought to estimate dietary niches for female bison at the levels of the forage items they consume and the macronutrients they acquire from those forage items. We assessed how these dietary niches changed seasonally and explored physical and climatic mechanisms that contribute to observed differences in the dietary niches. We also examined dietary differences between the two bison subspecies: wood bison Bison bison athabascae and plains bison Bison bison bison.We compiled data for 16 bison subpopulations using 26 peer‐reviewed publications, government reports, conference proceedings, and graduate theses that described the dietary composition of female bison for analysis of dietary niches.We found that the diets of female bison were, as expected, dominated by graminoids throughout the year, but during the growing season (spring and summer), dietary niches had greater breadth. Their diets were relatively high in carbohydrates, but percentages of dietary lipid and protein increased during the growing season. Further, we found significant increases in consumption of browse items, lipids, and proteins with increasing latitude (†N), and differences between American bison subspecies.Our study provides insight into the fundamental macronutrient niche of the American bison and also provides a framework for the nutritional targets of bison. We show that bison are able to adapt to availability of local forage and that they may consume different items in different proportions in order to regulate nutritional composition of their diet. [ABSTRACT FROM AUTHOR]

The boreal forest in Canada comprises a wide variety of ecosystems, including stabilized (overgrown) sand dunes, often referred to as sand hills. Globally, sandy soils are known for supporting a high diversity of invertebrates, including ants, but little is known for boreal systems. We used pitfall trap sampling in sand hill, aspen parkland and peatland ecosystems to compare their ant diversity and test the prediction that areas with sandy soils have higher invertebrate diversity compared to more mesic/organic soils. Overall, sand hills had ~45% more ant species compared to other sampled ecosystems from Alberta. Similar to other studies, local canopy cover within sand hills was found to be inversely related to ant species richness and diversity. Although sand hills are rare across the region, they are high biodiversity areas for ants, with the sand hills of north-central Alberta having higher species richness of ants compared to other studied areas in Canada. [ABSTRACT FROM AUTHOR]

In peatlands, microtopography strongly affects understory plant communities. Disturbance can result in a loss of microtopographic variation, primarily through the loss of hummocks. To address this, mounding treatments can be used to restore microtopography. We examined the effects of mounding on the understory vegetation on seismic lines in wooded fens. Seismic lines are deforested linear corridors (∼3 to 8 m wide) created for oil and gas exploration. Our objectives were to compare the recovery of understory communities on unmounded and mounded seismic lines and determine how recovery varies with microtopographic position. Recovery was evident in the unmounded seismic lines, with higher shrub and total understory cover at the "tops" of the small, natural hummocks than at lower microtopographic positions — much like the trends in adjacent treed fens. In contrast, mounding treatments that artificially created hummocks on seismic lines significantly changed understory communities. Mounded seismic lines had higher forb cover, much lower bryophyte cover, less variation along the microtopographic gradient, and community composition less similar to that of the reference sites than unmounded seismic lines due to higher abundance of marsh-associated species. Our results suggest that mounding narrow seismic lines can be detrimental to the recovery of the understory communities in treed peatlands. [ABSTRACT FROM AUTHOR]

Global and national commitments to slow biodiversity loss by expanding protected area networks also provide opportunities to evaluate conservation priorities in the face of climate change. Using recently developed indicators of climatic macrorefugia, environmental diversity, and corridors, we conducted a systematic, climate‐informed prioritization of conservation values across North America. We explicitly considered complementarity of multiple conservation objectives, capturing key niche‐based temperature and moisture thresholds for 324 tree species and 268 songbird species. Conservation rankings were influenced most strongly by climate corridors and species‐specific refugia layers. Although areas of high conservation value under climate change were partially aligned with existing protected areas, ∼80% of areas within the top quintile of biome‐level conservation values lack formal protection. Results from this study and application of our approach elsewhere can help improve the long‐term value of conservation investments at multiple spatial scales. [ABSTRACT FROM AUTHOR]

Railway networks contribute to the direct mortality of wildlife through collisions with trains, which can threaten vulnerable wildlife populations even in protected areas, including grizzly bears (Ursus arctos) in Banff and Yoho National Parks, Canada. Mitigation to reduce bear‐train collisions requires information about how grizzly bears use the railway spatially and temporally and how particular types of use might increase collision vulnerability. We used data from 27 grizzly bears fitted with global positioning system (GPS) collars between 2000 and 2016 to relate railway use by bears via resource selection functions to variables that described land cover, human use, and topography. We used the same suite of explanatory variables to distinguish pairs of 4 types of steps, in which 3 successive GPS points (with 2‐hr fix rates) included ≥1 within 30 m of the rail (hereafter on) and 2 others that defined locations where bears effectively entered the railway (first fix off rail, next 2 on), crossed it (only the middle fix on the rail), continued along the railway (all 3 fixes on), or exited the railway corridor (first 2 on, last off). We compared both sites of higher use and each of these 4 step types to the relative frequency of bear‐train collisions, predicting a positive correlation for continue step types. Relative to available locations, bears were more likely to use the railway close to railroad sidings (sections of twinned track where trains sometimes stop), at intermediate distances from human‐use features (e.g., town sites, highways, trails), in areas with lower values of the compound topographic index (a proxy for wetness; within 500 m), and within 90 m of rugged terrain. Seasonally, bears made greater use of the railway in spring and fall. Among 1,515 sequences of 3 steps, crossing locations comprised >50% and were most distinct from continue locations (about 20%), which occurred in areas with more rugged terrain (within 300 m), closer to railway sidings, in spring and fall, and with steps that were 60% shorter. Contrary to our prediction, past reports of bear‐train collisions were negatively correlated with continue locations and unrelated to overall use or any other movement type. Our results suggest that railway use by bears increased where it provided increased forage or easier travel, particularly in spring and fall, but more work will be needed to determine the mechanistic basis of bear‐train collisions. Meanwhile, mitigation efforts such as habitat alteration or warning systems might target locations where past strikes are concentrated for grizzly bears or other sensitive populations. © 2019 The Wildlife Society. Relative to available points, grizzly bears increased their use of a railway in areas that were at intermediate distances from areas of human use, closer to water bodies, with higher shrub cover, and with rugged topography. Among overall use and 4 movement types, designated as places where bears entered, exited, continued along, or crossed the railway, continue locations were unexpectedly negatively correlated with past locations of reported bear‐train collisions. [ABSTRACT FROM AUTHOR]

Butterflies have played a pivotal role in our understanding of animal movement, but little is known about landscape-scale movement in highly vagile species with large ranges and open population structure. We investigate the effect of environment and landscape on both inter- and intraspecific genetic differentiation and population structure in the Papilio machaon group of swallowtail butterflies in Alberta, Canada. These butterflies exhibit strong hilltopping behaviour, where individuals congregate on topographical prominences to mate, and thus we expect topography to influence population connectivity. We use redundancy analysis to explore the relationship between two genetic datasets (mitochondrial DNA and microsatellites) and topographic, climatic and habitat-related environmental variables at multiple spatial scales. Shared variation across these environmental variables explained a large portion of both mitochondrial (≤ 75%) and microsatellite genetic variation (≤ 40%). Individual variables, such as elevation, terrain profile, solar radiation and precipitation, had moderate explanatory power; however, the water component of land cover had the greatest explanatory power of the individual variables and acted as a surrogate variable for the larval habitat of P. machaon. Despite high levels of retained ancestral polymorphism in the mitochondrial dataset, we found similar relationships between environmental characteristics and genetic variation. Finally, the spatial scale of our analyses greatly influenced our results, and without exploring the effect of scale we would have missed or discounted the effects of several environmental characteristics. This point emphasizes the importance of exploratory analysis in systems where there is little prior knowledge of movement dynamics and the influence of the environment. [ABSTRACT FROM AUTHOR]

Wildlife population dynamics are modulated by abiotic and biotic factors, typically climate, resource availability, density‐dependent effects, and predator–prey interactions. Understanding whether and how human‐caused disturbances shape these ecological processes is helpful for the conservation and management of wildlife and their habitats within increasingly human‐dominated landscapes. However, many jurisdictions lack either long‐term longitudinal data on wildlife populations or measures of the interplay between human‐mediated disturbance, climate, and predator density. Here, we use a 50‐year time series (1962–2012) on mule deer (Odocoileus hemionus) demographics, seasonal weather, predator density, and oil and gas development patterns from the North Dakota Badlands, USA, to investigate long‐term effects of landscape‐level disturbance on mule deer fawn fall recruitment, which has declined precipitously over the last number of decades. Mule deer fawn fall recruitment in this study represents the number of fawns per female (fawn:female ratio) that survive through the summer to October. We used this fawn recruitment index to evaluate the composite effects of interannual extreme weather conditions, energy development, and predator density. We found that density‐dependent effects and harsh seasonal weather were the main drivers of fawn fall recruitment in the North Dakota Badlands. These effects were further shaped by the interaction between harsh seasonal weather and predator density (i.e., lower fawn fall recruitment when harsh weather was combined with higher predator density). Additionally, we found that fawn fall recruitment was modulated by interactions between seasonal weather and energy development (i.e., lower fawn fall recruitment when harsh weather was combined with higher density of active oil and gas wells). Interestingly, we found that the combined effect of predator density and energy development was not interactive but rather additive. Our analysis demonstrates how energy development may modulate fluctuations in mule deer fawn fall recruitment concurrent with biotic (density‐dependency, habitat, predation, woody vegetation encroachment) and abiotic (harsh seasonal weather) drivers. Density‐dependent patterns emerge, presumably due to limited quality habitat, being the primary factor influencing fall fawn recruitment in mule deer. Secondarily, stochastic weather events periodically cause dramatic declines in recruitment. And finally, the additive effects of human disturbance and predation can induce fluctuations in fawn fall recruitment. Here we make the case for using long‐term datasets for setting long‐term wildlife management goals that decision makers and the public can understand and support. [ABSTRACT FROM AUTHOR]

Variation in food abundance and distribution influences animal foraging behavior, but response is contingent on the amount of resource heterogeneity detected, which is consistent with environmental 'grain' size. Large mammals presumably perceive their surroundings at broad spatial scales, but the importance of landscape-level food resource properties for habitat use is generally less understood. We evaluated the role of heterogeneity of Canada buffaloberry Shepherdia canadensis, defined by fruit distribution and variability in patch quality (fruit density), in grizzly bear Ursus arctos habitat selection by comparing patch- and landscape-level foraging strategies (resource use). Our objectives were to: 1) identify the spatial scale at which grizzly bears select buffaloberry fruit resources; 2) determine whether patch- or landscape-level foraging strategies explain resource use; and 3) assess the importance of resource heterogeneity in structuring habitat selection. Buffaloberry patch and landscape variables were combined with GPS radio-telemetry data from eight collared grizzly bears in west-central Alberta, Canada, to fit resource selection functions (RSFs). We found that a spatial scale of 1887 m, corresponding to an average travel distance for bears over 5.5 h, was the most supported scale for buffaloberry use. Landscape-level foraging strategies generally had more support than those of the patch-level, with spatial heterogeneity of buffaloberry patches best explaining grizzly bear selection for fruit resources. Bears selected for areas with a wider distribution of buffaloberry fruit and greater variability in patch quality, thus providing both a higher probability of shrub encounter and greater contrast between resource patches. A negative interaction between distribution and variability, however, indicated a tradeoff where use of areas with a more widespread fruit distribution decreased when variability in resource quality was high. These results demonstrate the influence of food resource heterogeneity on animal habitat use and emphasize the value in considering spatial scale in studies of animal-resource interactions. [ABSTRACT FROM AUTHOR]

Understanding species responses to changes in habitat is a primary focus of biodiversity conservation, especially when assessing widespread anthropogenic disturbance. Extraction of Alberta's subterranean oil sands by wells requires extensive networks of cleared linear disturbances (“in situ” extraction) that result in widespread, but localized increases in early seral habitats. Little is known about biodiversity responses to these disturbances, especially for invertebrates. Here, we investigated how butterflies responded to in situ oil sands developments in the boreal forests of Wood Buffalo region, Alberta, Canada. To assess the magnitude of change associated with different disturbance types, we compared abundance and diversity of butterflies in undisturbed forests with those observed in 3-m and 9-m wide cleared corridors (seismic lines), 60 × 60 m clearings (well pads), and roadside verge habitat. The butterfly assemblage was evaluated based on disturbance type and three measures of landscape change: amount of early seral habitat, edge density, and diversity of natural habitats. Species richness was twice and abundance three-times higher in larger disturbances than in controls, with the narrowest corridors not differing from controls. A model using disturbance type, edge density, and habitat diversity explained 62% of assemblage variation, with the type of disturbance explaining 47%. Higher butterfly abundance and diversity occurred in localized early seral sites, even on 9-m wide corridors, while surrounding landscape characteristics had little effect. Results are consistent with previous studies finding stronger responses in vertebrates to larger disturbances associated with oil sands, confirming that narrower corridors mitigate the effects of oil sands exploration. [ABSTRACT FROM AUTHOR]

Variation in food abundance and distribution influences animal foraging behavior, but response is contingent on the amount of resource heterogeneity detected, which is consistent with environmental 'grain' size. Large mammals presumably perceive their surroundings at broad spatial scales, but the importance of landscape‐level food resource properties for habitat use is generally less understood. We evaluated the role of heterogeneity of Canada buffaloberry Shepherdiacanadensis, defined by fruit distribution and variability in patch quality (fruit density), in grizzly bear Ursus arctos habitat selection by comparing patch‐ and landscape‐level foraging strategies (resource use). Our objectives were to: 1) identify the spatial scale at which grizzly bears select buffaloberry fruit resources; 2) determine whether patch‐ or landscape‐level foraging strategies explain resource use; and 3) assess the importance of resource heterogeneity in structuring habitat selection. Buffaloberry patch and landscape variables were combined with GPS radio‐telemetry data from eight collared grizzly bears in west‐central Alberta, Canada, to fit resource selection functions (RSFs). We found that a spatial scale of 1887 m, corresponding to an average travel distance for bears over 5.5 h, was the most supported scale for buffaloberry use. Landscape‐level foraging strategies generally had more support than those of the patch‐level, with spatial heterogeneity of buffaloberry patches best explaining grizzly bear selection for fruit resources. Bears selected for areas with a wider distribution of buffaloberry fruit and greater variability in patch quality, thus providing both a higher probability of shrub encounter and greater contrast between resource patches. A negative interaction between distribution and variability, however, indicated a tradeoff where use of areas with a more widespread fruit distribution decreased when variability in resource quality was high. These results demonstrate the influence of food resource heterogeneity on animal habitat use and emphasize the value in considering spatial scale in studies of animal—resource interactions. [ABSTRACT FROM AUTHOR]

Life-history traits influence colonization, persistence, and extinction of species on islands and are important aspects of theories predicting the geographical distribution and evolution of species. We used data collected from a large freshwater lake (1,413 km2) in central Canada to test the effects of island area and isolation on species richness and abundance of carabid beetles as a function of body size, wing length, and breeding season. A total of 10,018 individual beetles from 37 species were collected during the frost-free period of 2013 using transects of pitfall traps on 30 forested islands ranging in area from 0.2 to 980.7 ha. Life-history traits improved the predictive ability and significantly modified the shape of species-area and abundance-area curves. Abundance and richness of small-bodied (< 13.9 mm), macropterous (winged), and spring-breeding species decreased with island area and increased with isolation. In contrast, richness and abundance of larger-bodied (> 14.0 mm) and flightless species increased with area, but not isolation. Body size of female Carabus taedatus Fabricius, the largest-bodied species, was positively related to island area, while body size on the adjacent mainland was most similar to that on smaller islands. Overall, species with large body size and low dispersal ability, as indicated by flightlessness, were most sensitive to reductions in area. We suggest that large-bodied, flightless species are rare on small islands because habitat is less suitable for them and immigration rates are lower because they depend on freshwater drift for dispersal to islands. [ABSTRACT FROM AUTHOR]

Distylous species typically experience self-incompatibility with one morph often having partial self-compatibility. Small populations may therefore experience greater rates of selfing/intramorph crosses leading to skewed morph ratios and reduced seed production. For the distylous species Houstonia longifolia Gaertn. ('imperiled' at its northwestern range limit in Alberta), we examined whether small populations were morph-biased and whether seed production was affected by population size, local density, plant size, morph type, and surrounding morph ratio. For focal plants in several populations, we measured size (height, number of stems) and local density (1 m2) of pins and thrums, with the focal plants collected for seed counts. Population size was estimated from densities in systematically located quadrats in each population. Morph ratios were pin-biased in small populations but were even to slightly thrum-biased in large populations. The critical population size for maintaining an equal morph ratio was ∼726 plants. Seed production was most influenced by the interaction between morph type and surrounding morph ratio, which were themselves influenced by population size (Allee effect). Seed production increased for thrums but decreased for pins as the proportion of surrounding pins increased, suggesting strong incompatibility. These results provide guidance on population size and morph ratios for conservation actions. [ABSTRACT FROM AUTHOR]

Satellite remote sensing provides a rapid and broad-scale means for monitoring vegetation phenology and its relationship with fluctuations in air temperature. Investigating the response of plant communities to climate change is needed to gain insight into the potentially detrimental effects on ecosystem processes. While many studies have used satellite-derived land surface temperature (LST) as a proxy for air temperature, few studies have attempted to create and validate models of forest understory temperature (Tust), as it is obscured from these space-borne observations. This study worked to predict instantaneous values of Tust using daily Moderate Resolution Imaging Spectroradiometer (MODIS) LST data over a 99,000 km2 study area located in the Rocky Mountains of western Alberta, Canada. Specifically, we aimed to identify the forest characteristics that improve estimates of Tust over using LST alone. Our top model predicted Tust to within a mean absolute error (MAE) of 1.4 °C with an overall model fit of R2 = 0.89 over two growing seasons. Canopy closure and the LiDAR-derived standard deviation of canopy height metric were found to significantly improve estimations of Tust over MODIS LST alone. These findings demonstrate that canopy structure and forest stand-type function to differentiate understory air temperatures from ambient canopy temperature as seen by the sensor overhead. [ABSTRACT FROM AUTHOR]

High-quality ground-truth data are critical for developing reliable Earth Observation (EO) based geospatial products. Conventional methods of collecting these data are either subject to an unknown amount of human error and bias or require extended time in the field to complete (i.e., point-intercept assessments). Digital photograph classification (DPC) may address these drawbacks. In this study, we first assess the performance of a DPC method developed through licensed software to estimate ground cover percentage (%) of bright lichens, a critical caribou forage in fall and winter when other food resources are scarce. We then evaluate the feasibility of replicating this workflow in an open-source environment with a modified U-net model to improve processing time and scalability. Our results indicate that DPC is appropriate for generating ground-truth data in support of large-scale EO-based lichen mapping within the boreal forests of eastern Canada. Our final open-sourced classification model, Lichen Convolutional Neural Network (LiCNN), is comparably accurate yet more efficient than the licensed workflow. Therefore, the LiCNN approach successfully addresses the mentioned shortcomings of conventional ground-truth data collection methods efficiently and without the need for specialized software. [ABSTRACT FROM AUTHOR]

ABSTRACT We analyzed a unique 51-year time series for a population of mule deer in the North Dakota badlands, USA to examine the effects of seasonal weather on autumn recruitment. Winter weather recorded prior to birth of fawns and weather conditions recorded during spring the previous year (lagged effect), but not during spring or summer after birth, were related to observed patterns in autumn recruitment. When deer density was low (approx. 1 deer/km2) during the 1960s, fawn/female ratios were high ranging from 1.1 to 1.4 when minimum temperatures during the prior winter averaged −16° C and −8° C, respectively. Likewise, during the 2000s, when deer density was high (approx. 3 deer/km2), fawn/female ratios ranged from 0.6 to 0.9 when minimum daily temperatures during the previous winter were −16° C and −8° C, respectively. Large-scale Pacific-based climatic indices (>2,000 km to the Pacific coast) were correlated with local weather and helped explain variability in autumn recruitment. Higher values of the multivariate el niño southern oscillation and Pacific decadal oscillation were correlated with warmer and drier winters in the North Dakota badlands, whereas the North Pacific Index was correlated with colder and snowy winters. The ability to predict recruitment from local weather or from broad-scale climate indices (oscillations) provides greater opportunities for conservation and management, such as adjusting harvest quotas prior to autumn harvest. © 2015 The Wildlife Society. [ABSTRACT FROM AUTHOR]