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• Our study addresses biases and uncertainties of cumulative pressure maps. • Map's accuracy significantly improves with an increase in the number of layers. • Uncertainties in intensity scores moderately affect overall accuracy. • Additive and antagonist cumulative models exhibit a robust correlation. Understanding how human activities are altering landscapes is critical to address habitat loss and biodiversity decline. Cumulative pressure mapping has emerged as a tool to quantify both the extent and intensity of multiple forms of human activities on the environment. However, there are several approaches to selecting and combining individual spatial layers into cumulative pressure maps, without clear guidance on how these methods affect the accuracy of the resulting maps. Here, we evaluated how the number of individual pressures, and changes in their intensity scores influenced the accuracy, measured against visual interpretation of high-resolution imagery, of a cumulative pressure map for a large, ecological diverse province, British Columbia, Canada. Additionally, we compared additive and antagonist models for combining pressures, which are among the most widely employed models in terrestrial studies. We started by identifying 16 human pressures and their associated spatial representation (i.e., layer) across the province. We then compared the validation values and the outcomes of 100,000 simulations in which we tested different perturbations of the human pressure model. Model accuracy improved with the inclusion of each additional pressure layer, reaching an average mean absolute error of 0.09 with the full spectrum of pressures. Our findings suggested that variations in intensity scores assigned to individual pressures only moderately influenced the resulting cumulative pressure score. In our final analysis, we observed a robust correlation between the additive and the antagonist models, particularly in regions that were either relatively free of human disturbance or highly modified by disturbances. Our study provides an empirical basis for continued improvements to practices for cumulative pressure mapping, addressing methodological challenges that were not formally considered in previous studies. [ABSTRACT FROM AUTHOR]

Highlights • There is variability in the abundance of terrestrial lichen following wildfire. • Forest stand characteristics are the most influential predictors of lichen volume. • Stand age is influential, but not a significant predictor of lichen abundance. • Some recent burns may have enough biomass to support foraging by caribou. Abstract Forest fires are the most dominant natural disturbance process influencing the habitat and distribution of woodland caribou (Rangifer tarandus caribou) in winter. This is a function of terrestrial lichens, the primary winter forage of caribou, taking decades to recover following fire. Working across the range of the Klaza caribou herd in the west-central Yukon, Canada, we used statistical count models to evaluate variation in lichen volume and percent cover among burns of different age classes. Burns of the same age had considerable variation in lichen abundance. Forage lichens were more abundant in coniferous stands with greater canopy openness, tree height, and basal area. Although not a significant parameter in models of volume or percent cover of lichen, time since burn improved model performance. Relative to thresholds in the published literature, most stands had sufficient lichen at 50 years post fire to be considered winter range for caribou. The relationship between caribou and burned landscapes is complex suggesting that wildlife and forest managers should look beyond burn age when accounting for the effects of fire on the availability and quality of winter habitat for woodland caribou. [ABSTRACT FROM AUTHOR]

To gain a better understanding of the dynamics of moose-vehicle collisions, we analyzed 96 videos of moose-vehicle interactions recorded by vehicle dash-mounted cameras (Dash Cams) that had been posted to the video-sharing website YouTube™. Our objective was to determine the effects of road conditions, season and weather, moose behavior, and driver response to actual collisions compared to near misses when the collision was avoided. We identified 11 variables that were consistently observable in each video and that we hypothesized would help to explain a collision or near miss. The most parsimonious logistic regression model contained variables for number of moose, sight time, vehicle slows, and vehicle swerves (AIC c w  = 0.529). This model had good predictive accuracy (AUC = 0.860, SE = 0.041). The only statistically significant variable from this model that explained the difference between moose-vehicle collisions and near misses was ‘Vehicle slows’. Our results provide no evidence that road surface conditions (dry, wet, ice or snow), roadside habitat type (forested or cleared), the extent to which roadside vegetation was cleared, natural light conditions (overcast, clear, twilight, dark), season (winter, spring and summer, fall), the presence of oncoming traffic, or the direction from which the moose entered the roadway had any influence on whether a motorist collided with a moose. Dash Cam videos posted to YouTube™ provide a unique source of data for road safety planners trying to understand what happens in the moments just before a moose-vehicle collision and how those factors may differ from moose-vehicle encounters that do not result in a collision. [ABSTRACT FROM AUTHOR]

Across western Canada, furbearers are being subjected to the cumulative impacts of industrial development. This region has witnessed unprecedented levels of anthropogenic change, primarily in the form of increased forest harvesting. We used trapping records to investigate the relationship between habitat and the abundance of Canada lynx ( Lynx canadensis ) and American marten ( Martes americana ). We applied expert-based habitat models to ten reference landscapes (i.e., traplines) in two distinct study areas to serve as measures of habitat change from 1990 to 2013. We elicited fur harvest records from trapper experts and then used negative binomial count models to relate capture success to habitat availability and quality. We controlled for factors that were hypothesized to influence capture success, including effort and weather conditions, allowing us to model the effects of habitat availability and quality on population abundance. Expert-based habitat models revealed that the area and quality of habitat declined significantly as a result of increased forest harvesting. The top-ranked count models identified combinations of habitat availability and quality, trapping effort, and trapline area as factors positively influencing the capture success of lynx and marten. Results suggested that the reduction in high-quality habitat negatively affected the abundance of marten in the study area. Methods and findings also illustrated the utility of harvest records for investigating population abundance of furbearer species. A precise measure of trapping effort, however, is necessary to relate environmental covariates, including habitat, to harvest at the scale of individual traplines. [ABSTRACT FROM AUTHOR]

Aboriginal communities can be negatively affected by resource development, but often they do not have a full opportunity to participate in project review and the resulting monitoring and mitigation activities. Cumulative impacts of resource development are also typically neglected in monitoring protocols that focus on a limited number of environmental values, rather than adopting a long-term, holistic view of development over time and space. Community-based environmental monitoring (CBEM) is emerging as a way to meaningfully include local Aboriginal citizens in the decision-making process as well as the assessment of the long-term impacts of the development of natural resources. We explored opportunities and barriers for developing CBEM programs that meet the needs of small and rural Aboriginal communities that are faced with the rapid and wide-spread development of natural resources. We conducted interviews with a local Aboriginal community, and natural resource management practitioners who could provide perspectives on the application of CBEM to resource management in north-central British Columbia, Canada. Results demonstrate that CBEM offers a locally adapted and culturally appropriate approach to facilitate the participation of Aboriginal communities in natural resource decision making and management. The interpretation of the specific role and purpose of CBEM differed among participants, depending on their objectives for and concerns about natural resource development. However, all parties were consistent in viewing CBEM as an effective method for engaging in dialogue, cooperation, and tracking environmental change. The development or improvement of CBEM programs should consider the efficacy of monitoring protocols, social cohesion and relationships, ability to inform decision-making, and effectiveness of CBEM for the members of the community. [ABSTRACT FROM AUTHOR]

• Industrial forest harvesting changes forest structure and composition. • Studied diet of moose across range of logging intensity. • Forest harvesting can affect diet of moose. Human-caused landscape disturbance is one of the major threats to large herbivores, globally. Across central British Columbia (BC), Canada, industrial forest harvesting has resulted in rapid change to forest structure and composition. Concurrent with the increase in forest harvesting, moose (Alces alces) populations across central BC have declined, some dramatically. We studied moose diet across three seasons in two regional study areas that represented a range of logging intensity and rate of apparent starvation of moose. We used microhistological analysis of pellets to identify the proportional consumption of major plant groups that were known forage for moose across the study areas, as well as the diversity of the diet of moose. We used regression models to test whether the composition and diversity of moose diet in two study areas were consistent with the Niche Expansion Hypothesis or the Niche Shrinkage Hypothesis. In areas of increased density and size of clearcuts, moose consumed fewer shrubs and fir trees and their diet was more diverse. Where application of herbicides was common, moose consumed fewer forbs and their diet was more diverse. Both responses were consistent with the Niche Expansion Hypothesis. In areas of increased disturbance by wildfire, moose consumed less fir and more shrubs. Our results suggest that landscape disturbance in the form of extensive and rapid forest harvesting can influence the composition and diversity of the diet of moose. [ABSTRACT FROM AUTHOR]

Habitat change is a major driver of species distribution and persistence, but there have been few recorded extinction events for terrestrial mammals across Canada. Currently, we are observing the decline, extirpation, and perhaps extinction of several evolutionarily significant units of woodland caribou ( Rangifer tarandus caribou ), an iconic and cultural keystone species. We used an extensive set of caribou locations (5 subpopulations, 102 animals, 270,808 GPS-collar locations) collected over 11 years within the Central Mountain Designatable Unit to develop species distribution models that quantified avoidance by caribou of anthropogenic and natural disturbance features. Those empirical relationships allowed us to measure the loss of habitat over a 22-year period and correlate habitat change with measured population decline. The disturbance responses for caribou were complex and varied by season and subpopulation. We modelled a zone of influence for roads (1.75 km), seismic and pipelines (2.5 km), oil and gas features (4.25 km), cutblocks (5.5 km), burns (8.0 km), and coal mines (3.0 km). When the distribution models for each subpopulation were applied to the respective seasonal ranges, we measured a maximum loss in high-quality habitat of 65.9%. The reduction in habitat was strongly correlated with the annual multiplicative growth rate of 5 subpopulations of caribou. At current rates of habitat loss and population decline, these caribou, a significant component of Canada’s biodiversity, are unlikely to persist. Although the factors leading to extinction are complex, the cumulative impacts of industrial development are a correlative if not causative factor. [ABSTRACT FROM AUTHOR]

Caribou and reindeer (Rangifer spp.) are known to respond negatively to human activities. Disturbance stimuli can result in short-term behavioural responses or the abandonment of portions of seasonal range. There is relatively little understanding, however, of the ability of caribou to adapt or habituate to long-term human-caused disturbance. We fit species distribution models to 27 years of location data collected for the Porcupine caribou herd (Alaska, USA; Yukon and Northwest Territories, Canada) during winter. We used a novel technique to quantify the avoidance responses and zone of influence associated with human settlements, main roads and minor disturbance features including wells, trails, and seismic lines. We hypothesised that during the early period of monitoring (1985-1998), caribou would demonstrate a greater sensitivity to human disturbance and a larger zone of influence relative to industrial development. Consistent with the assumed level and timing of disturbance, caribou demonstrated the strongest avoidance response to settlements, followed by main roads and minor disturbance features. The data suggested that avoidance, noted as the zone of influence, was less during the more recent time period (1999-2012), but still relatively large when compared to the reported disturbance responses of other populations of Rangifer. A precise habituation response was obscured by uncertainty in the data describing human activities and variation in the distribution and population dynamics of the herd for such an extensive time period. These results suggest that the large-scale behavioural responses of wide-ranging mammals to disturbance stimuli are dynamic. The study of such responses requires accurate data describing human activities as well as long-term monitoring and periodic evaluation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ecological thresholds are proposed as a method to identify acceptable levels of human activities. [•] Numerous definitions confound the identification and application of thresholds. [•] Empirical studies suggest that thresholds do not generalize across species. [•] There is little evidence of the successful application of thresholds to conservation decision making. [•] Regulatory limits consider socioeconomics and conservation risk when guiding acceptable levels of development. [ABSTRACT FROM AUTHOR]

Models that predict distribution are now widely used to understand the patterns and processes of plant and animal occurrence as well as to guide conservation and management of rare or threatened species. Application of these methods has led to corresponding studies evaluating the sensitivity of model performance to requisite data and other factors that may lead to imprecise or false inferences. We expand upon these works by providing a relative measure of the sensitivity of model parameters and prediction to common sources of error, bias, and variability. We used a one-at-a-time sample design and GPS location data for woodland caribou (Rangifer tarandus caribou) to assess one common species-distribution model: a resource selection function. Our measures of sensitivity included change in coefficient values, prediction success, and the area of mapped habitats following the systematic introduction of geographic error and bias in occurrence data, thematic misclassification of resource maps, and variation in model design. Results suggested that error, bias and model variation have a large impact on the direct interpretation of coefficients. Prediction success and definition of important habitats were less responsive to the perturbations we introduced to the baseline model. Model coefficients, prediction success, and area of ranked habitats were most sensitive to positional error in species locations followed by sampling bias, misclassification of resources, and variation in model design. We recommend that researchers report, and practitioners consider, levels of error and bias introduced to predictive species-distribution models. Formal sensitivity and uncertainty analyses are the most effective means for evaluating and focusing improvements on input data and considering the range of values possible from imperfect models. [Copyright &y& Elsevier]

Woodland caribou (Rangifer tarandus caribou) are sensitive to changes in understory vegetation resulting from forest harvesting and are, therefore, of special concern for foresters and habitat biologists. Effective management of this species requires reliable habitat inventories which, because of the large heterogeneous areas over which caribou range, can be costly. We used Landsat Thematic Mapper (TM) imagery and digital elevation data to identify 23 vegetative cover types across the 5100 km2 range of the Wolverine caribou herd of northcentral British Columbia, Canada. The classification was augmented with available geographical information system (GIS) data for a total of 27 cover types. We achieved an overall accuracy of 76.7% based on known ground samples; however, accuracy varied according to cover type. Considering the size of the study area, the procedure we employed was relatively cost effective and efficient. We discuss the advantages of such an approach for wildlife-habitat studies reliant on large-scale vegetation maps. [Copyright &y& Elsevier]

• Habitat selection of post-metamorphic coastal tailed frog. • Monitoring movement of amphibians with radio telemetry. • Effect of clearcut harvesting and streamside forest retention. • Coastal tailed frog associated with coarse woody debris, less light, larval stream. The coastal tailed frog (Ascaphus truei) has a biphasic life-history that includes the use of montane streams adjacent to mature old growth forests. This species is at risk from a variety of land-use activities, including forest harvesting, that results in younger and more fragmented terrestrial habitats. Post-metamorphic tailed frogs are cryptic and difficult to capture, making for few studies of the terrestrial life stage of the species. At the northern extent of the species' range, we investigated the spatial ecology of tailed frogs across riparian and adjacent upland forest in three forest types: mature to old unharvested, streamside forest retention, and clearcut. Post-metamorphic frogs were fitted with Very High Frequency radio transmitters and monitored for an average of 10.75 days (SE 0.89). Females moved further from their origin of capture during the monitoring period (x ¯ = 68.89 m, SE 16.3) when compared to males (x ¯ = 36.85 m, SE 7.9). We used Resource Selection Functions to quantify habitat selection of female and male tailed frogs. Monitored frogs were positively associated with habitats containing well-decayed coarse woody debris (≥ 7.5 cm diameter), less ambient light, adjacency to the larval stream, hygric and subhygric microsites, and cool temperatures (11–12 °C). Females were more selective in their choice of habitat than males. Overall, the relationship between distribution and activity of tailed frogs was reflective of the sex of the frog in combination with microsite or broader climatic conditions ameliorated by stand-level habitat conditions. Our data suggest that habitat management for post-metamorphic tailed frogs focus on the retention of both streamside (within 40 m) and upland forest (> 50 m from larval stream), as well as stand-level attributes such as hygric and subhygric microsites, and coarse woody debris with advanced decay. [ABSTRACT FROM AUTHOR]

• Apex mesocarnivores important to conservation of island ecosystems. • Ecology of Pacific marten not well understood across intensively managed forests. • Marten associated with habitat containing some component of forest edge and road. • Foraging likely adapted to invasive Sitka black-tailed deer and forest management. • Competition and predation may contribute to regulation of species at risk on Haida Gwaii. Apex mesocarnivores can have a large influence on the functioning of plant and animal communities. Such effects can be more pronounced in relatively depauperate island ecosystems, especially in the context of a legacy of landscape change and introduced species. One such ecosystem is Haida Gwaii, British Columbia, Canada, where a long history of introduced species and forest harvesting has greatly influenced the composition of the plant and animal communities. Most notably, Sitka black-tailed deer (Odocoileus hemionus sitkensis), an introduced and unchecked invasive species, has interacted with forest harvesting to greatly change the understory structure and composition of those temperate rainforests. Little is known of the habitat ecology of Pacific marten (Martes caurina), the small-bodied apex predator on those islands. We used camera traps to monitor the distribution and habitat ecology of marten across 2 winters. We used mixed-effects logistic regression to test 14 a priori hypotheses represented by statistical models formulated at two spatial scales (100 and 1000 m), with four categories of explanatory factors: sampling bias, forest structure, topography, and human disturbance. Relationships between detections and covariates from the top models revealed that at the 100-m scale, marten were more likely to use habitat that was closer to streams and marine shorelines and that contained a small area of forest harvesting. Marten detections were associated with habitat containing some component of forest edge and road, suggesting foraging behavior adapted to invasive deer, an important source of carrion for marten during winter. The broad use of habitats by Pacific marten suggests that intraguild competition and predation might occur with several species at risk including the endemic Haida ermine (Mustela ermine haidarum). Those two species would likely overlap in diet and distribution when co-occurring across low-elevation coastal habitats. Conservation planning on Haida Gwaii should consider measures that decrease the potential for competition or predation between marten and species at risk. [ABSTRACT FROM AUTHOR]

Nature-based activities promote human-fauna encounters, which may be perceived as a type of predation risk. This pattern of human avoidance is well-known, but is often related to major anthropogenic disturbances. The response of animals to less intensive or ephemeral human activities, such as backcountry skiing and hiking is not well studied. Yet, these activities occur in many protected areas, where managers are trying to conserve some of the most threatened species. This is the case for the Endangered Atlantic-Gaspésie mountain caribou in the Gaspésie National Park. To assess the impact of backcountry skiing, we used GPS telemetry to monitor 20 caribou frequenting a ski area partially included in the Park. More than 12% of caribou locations were within the ski area when skiers were absent. Use of that area by caribou decreased to 6% when there were skiers. Coefficients from a resource selection function suggested that caribou avoided the ski area, and the disturbance response was modulated by the number of skiers. Caribou were not significantly displaced within the first 6 h of exposure to skiers, but thereafter moved away from the ski area for ~ 48 h to lower elevation habitats where predation from coyotes was potentially greater. Our results revealed a relatively strong disturbance response and corresponding functional loss of a possible noticeable portion of habitat as a result of backcountry skiing. Park managers should consider even small numbers of recreationists as they could have an important impact on animal distribution. [ABSTRACT FROM AUTHOR]

Abstract Management of wildlife often relies upon understanding mechanisms linking anthropogenic disturbance to population declines. The most-cited mechanism by which disturbance threatens boreal caribou (Rangifer tarandus caribou) is the exacerbation of apparent competition via increases in early successional forage, and subsequent changes in the densities and distributions of other prey species and gray wolves (Canis lupus). An alternative mechanism is the direct alteration of wolf distribution via positive responses by wolves to anthropogenic features. We conducted a mechanistic evaluation of hypotheses explaining human-mediated increases in boreal caribou mortality across northeast British Columbia. We evaluated support for (i) numeric apparent competition (increased prey densities) by evaluating relationships between disturbances, moose (Alces alces) density, and caribou survival. To evaluate (ii) spatial apparent competition (altered prey distribution) and (iii) wolf spatial responses (altered wolf distribution independent of prey), we modeled the relationships between disturbances and indices of caribou-moose and caribou-wolf co-occurrence and then examined predation risk for caribou as a function of co-occurrence. We did not detect any relationships between anthropogenic disturbances, moose density, and caribou survival. Although caribou-moose co-occurrence increased predation risk, we observed both positive and negative relationships between disturbances and caribou-moose co-occurrence. In contrast, caribou-wolf co-occurrence increased predation risk and was positively correlated with anthropogenic linear features. Contrary to other boreal caribou populations, our analyses demonstrate stronger support for the direct effects of anthropogenic linear features on caribou-wolf spatial overlap, leading to greater risk for caribou. Our research highlights the need for region-specific management actions to conserve and recover widely distributed species. Highlights • Boreal caribou are federally listed as threatened across their range as a result of resource extraction • Human-mediated apparent competition with other prey species is theorized as the primary mechanism of decline • In northeast British Columbia, the effect of anthropogenic linear features on caribou-wolf encounters is better supported • Limiting future and restoring existing linear features is recommended for caribou recovery in northeast British Columbia • Regional management actions are often necessary for the conservation of widely distributed species [ABSTRACT FROM AUTHOR]

Abstract: Background: One measure of the accuracy of cancer mortality statistics is the concordance between cancer defined as the underlying cause of death from death certificates and cancer diagnoses recorded in central, population-based cancer registries. Previous studies of such concordance are outdated. Objective: To characterize the accuracy of cancer mortality statistics from the concordance between cancer cause of death and primary cancer site at diagnosis. Design: Central cancer registry records from California, Colorado, and Idaho in the U.S. were linked with state vital statistics data and evaluated by demographic and tumor information across 79 site categories. A retrospective arm (confirmation rate per 100 deaths) compared death certificate data from 2002 to 2004 with cancer registry diagnoses from 1993 to 2004, while a prospective arm (detection rate per 100 deaths) compared cancer registry diagnoses from 1993 to 1995 with death certificate data from 1993 to 2004 by International Statistical Classification of Diseases and Related Health Problems (ICD) version used to code deaths. Results: With n =265,863 deaths where cancer was recorded as the underlying cause based on the death certificate, the overall confirmation rate for ICD-10 was 82.8% (95% confidence interval [CI], 82.6–83.0%), the overall detection rate for ICD-10 was 81.0% (95% CI, 80.4–81.6%), and the overall detection rate for ICD-9 was 85.0% (95% CI, 84.8–85.2%). These rates varied across primary sites, where some rates were <50%, some were 95% or greater, and notable differences between confirmation and detection rates were observed. Conclusions: Important unique information on the quality of cancer mortality data obtained from death certificates is provided. In addition, information is provided for future studies of the concordance of primary cancer site between population-based cancer registry data and data from death certificates, particularly underlying causes of death coded in ICD-10. [Copyright &y& Elsevier]