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Abstract Understanding how conservation of woodland caribou, an at-risk species for which large undisturbed areas are often proposed to maintain viable populations, can contribute to conservation of boreal biodiversity is an important consideration for an ecosystem warming at twice the global average and experiencing rapid resource development. We assess the focal or 'umbrella' value of the boreal population of woodland caribou for conservation of mammalian and avian richness (n = 432) in the boreal region of Canada by (i) evaluating co-occurrence of caribou distribution with that of boreal mammals (n = 102), birds (n = 330), at-risk mammals (n = 11) and at-risk birds (n = 47); and (ii) conducting systematic conservation planning using MARXAN software to identify minimum representative and complementary reserve networks, comprised of planning units deemed large enough (10,000 km2) for persistence of terrestrial wildlife, both at the extent of boreal caribou distribution and the entire boreal region. While boreal caribou overlap with the range of 90% of boreal birds and mammals, area-efficient networks representative of boreal diversity focus on species-rich areas south of caribou distribution and other areas that contain relatively small-ranged species. A similar pattern occurs when the MARXAN analysis focused only on caribou distribution, i.e. representative networks are preferentially located on southern herd ranges. However, this situation differs markedly to include large areas within the distribution of caribou if anthropogenic footprint on the landscape is considered as a constraint on reserve design. Efforts to sustain boreal caribou offer considerable opportunities to conserve diversity of co-occurring mammals and birds, including areas of the relatively more disturbed caribou southern ranges that have irreplaceable value in an efficient and representative pan-boreal network of reserves. The high focal value of boreal caribou for animal diversity should be considered when making decisions and policy choices about how to best allocate conservation efforts across its extensive distribution. [ABSTRACT FROM AUTHOR]

Abstract Anthropogenic disturbances fragmenting wildlife habitat greatly contribute to extinction risk for many species. In western Canada, four decades of oil and gas exploration have created a network of seismic lines, which are linear disturbances where seismic equipment operates. Seismic lines cause habitat fragmentation and increase predator access to intact forest, leading to declines of some wildlife populations, particularly the threatened woodland caribou, Rangifer tarandus caribou. Restoration of forests within seismic lines is an important activity to reduce habitat fragmentation and recovery caribou. We present an optimization model with the objective of guiding landscape restoration strategies that maximize the area of connected habitat for a caribou population in a fragmented landscape. We use our model to find optimal strategies for seismic line restoration in the Cold Lake Area of Alberta, Canada, a 6726-km2 expanse of boreal forest that represents prime caribou habitat. We formulate mixed integer programming models that depict the landscape as a network of interconnected habitat patches. We develop and compare formulations that emphasize the population's local or long-distance access to habitat. Optimal restoration involves a mix of two strategies: the first establishes short-distance connections between forest patches with large areas of intact habitat and the second establishes corridors between areas with known species locations and large amounts of suitable habitat. Our approach reveals the trade-offs between these strategies and finds the optimal restoration solutions under a limited budget. The approach is generalizable and applicable to other regions and species sensitive to changes in landscape-level habitat connectivity. [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]

Abstract Unspoiled wildlands of boreal landscapes provide critical habitats for wildlife. With the increase in resource development across Canada's boreal zone, woodland caribou (Rangifer tarandus caribou) and grizzly bears (Ursus arctos) are at risk of population declines. We used 4 planning scenarios with variants of these in decision-support software Marxan to allocate potential conservation priority areas for caribou and grizzly bears in boreal wildlands of the Muskwa-Kechika Management Area in northeast British Columbia, Canada. For caribou and grizzly bears across their seasonal habitats, priority areas allocated to preserve connectivity of habitat patches maintained more intact high-value habitats, with moderate opportunity cost for resource development, than those allocated under other scenarios. In winter when high-value habitats of caribou tend to coincide with resource-rich areas, priority areas allocated to preserve areas that are more vulnerable to development maintained more intact high-value habitats with higher opportunity cost (therefore greater adverse economic consequences) than those allocated in areas with lower resource potential. In growing-season (non-winter) habitats of caribou and grizzly bears, allocating priority areas toward either more vulnerable or less vulnerable areas did not substantially affect patch and landscape characteristics of conserved habitats. Priority areas intended to avoid predation risk for caribou were not effective in maintaining intact high-value habitats for caribou in these undeveloped wildlands. Conserving connectivity would best maintain most intact habitats for both species across seasons; conserving habitats most vulnerable to development also would discourage future development outside of the conserved areas in winter habitats of caribou. Findings from these conservation planning scenarios have implications globally to other areas where sensitive species are threatened by pending resource developments. Highlights • Maintain connectivity to preserve high-value habitats of caribou and grizzly bears. • Avoiding predation risk does not always maintain intact habitat for caribou. • Conserving most vulnerable winter caribou habitat helps ensure spatial integrity. • Conservation priority areas may necessitate lost opportunities for resource development. [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]

Highlights • Trichinella spiralis prevalence in wildlife is influenced by the domestic cycle. • T. spiralis eradication from domestic habitat reduces prevalence among wildlife. • Spillover from domestic pigs as a source of T. spiralis in wildlife. Abstract Carnivore and omnivore animals are the main reservoir hosts of nematodes of the genus Trichinella. Out of the twelve taxa identified so far in the world, four, namely Trichinella spiralis , Trichinella nativa , Trichinella britovi and Trichinella pseudospiralis , are circulating in Europe. All these four species were detected in Finnish wild animals and T. spiralis also in domestic pigs and synanthropic rats of Finland up to 2004, when the last T. spiralis infection was documented in a domestic pig. In the periods 1993–1997 and 1999–2005, T. spiralis was detected in 13.6% (6/44) and in 14.5% (46/317) of infected wild animals, respectively. The aims of the present study were to investigate the prevalence of Trichinella spp., especially T. spiralis in wild carnivores of Finland, 7–9 years after the eradication of Trichinella infection from Finnish domestic pigs, and to evaluate the impact of the disappearance of domestic cycle of T. spiralis on the sylvatic Trichinella cycle(s). Trichinella spp. larvae were detected in 34.7% (1081/3112) wild animals and 835 (77.2%) Trichinella spp. isolates were identified at the species level. Trichinella spiralis was detected in 9 animals (1.0% of identified infections) as single, double or triple infections; whereas, T. spiralis had been detected in 13.6% and in 14.5% of infected wild animals in the course of the two previous investigations. The reduction of T. spiralis prevalence from 1993–1997 to 2011–2013 is statistically significant (p < 0.001) both per total tested animals and per host species. The results of this study support the hypothesis of spillover from domestic pigs as a source of T. spiralis in wildlife. The eradication of T. spiralis from the domestic cycle in Finland in 2004 has probably established a virtuous cycle reducing the prevalence of this pathogen among wild carnivores. We can expect that within some years and in absence of T. spiralis reintroduction in the domestic habitat, it might even disappear from the Finnish wildlife. [ABSTRACT FROM AUTHOR]

Fire is the major disturbance agent in boreal forests that initiates forest regeneration and succession, and plays a major role in determining the composition of terricolous lichen communities. In recent decades however, logging has become an important disturbance agent in boreal forests. In this context, growing concerns about logging effects on endangered species such as woodland caribou ( Rangifer tarandus caribou ) has emerged and drawn attention on how reindeer lichens (i.e. Cladonia arbuscula , Cladonia mitis , Cladonia rangiferina , Cladonia stellaris , and Cladonia stygia ) respond to logging and fire given their importance as winter forage for caribou. We compared critical lichen habitat factors (i.e., forest floor thickness, tree height, and canopy closure) between fire and logged sites and evaluated how Cladonia lichen species richness, biomass, and ground cover were related to these habitat factors in the first decades following disturbance. We found no significant differences in habitat factors and no significant differences in lichen species richness or ground cover between logged and fire sites. However, Cladonia lichen biomass was significantly higher following logging. These results support the hypothesis that Cladonia lichens can persist following logging and suggest that forestry practices that include in their toolbox winter harvesting or machinery traffic restricted to specific trails are likely to preserve undisturbed forest floor habitat conditions with source populations of lichens. [ABSTRACT FROM AUTHOR]

Human activities can impact animal communities by altering species interactions. The influence of forest harvesting on the interaction between threatened boreal caribou, moose, and wolves constitutes a classic example. When conifer forests are logged, clear-cuts are colonized by deciduous vegetation that provides high-quality food for moose. Subsequent changes in wolf distribution alter predation risk for caribou. Given that primary productivity varies along latitudinal gradients, the effects of logging on moose-caribou-wolf interactions could also vary moving northwards. Empirical evidence, however, is lacking and current recommendations for caribou conservation are fixed over space. We assessed whether the impact of logging activities on caribou-moose-wolf interactions varies with latitude. We estimated deciduous vegetation availability from satellite imagery, and followed all three species with GPS collars to evaluate their habitat selection. We found that the availability of deciduous vegetation in logged stands decreased along a 400-km latitudinal gradient. The probability of caribou occurrence remained low in clear-cuts, regardless of deciduous vegetation availability. Moose and wolves increased their selection for clear-cuts as they contained more deciduous vegetation. Accordingly, the relative co-occurrence probability of moose and wolves was strongly associated with clear-cuts at low latitudes, but weakly so at high latitudes. Clear-cuts should therefore attract moose and wolves more strongly to prime boreal caribou habitat at lower latitudes, and caribou predation risk should follow similar geographical patterns. Conservation planning should account for geographical patterns in the risk faced by threatened populations because the effectiveness of strategies developed from average patterns can decrease over space, in consistent manner. [ABSTRACT FROM AUTHOR]

Boreal forest development is influenced by both natural and anthropogenic disturbances that alter stand structure and nutrient cycling over decadal timescales. The effects of disturbance on boreal forests is likely to be modified by soil moisture, given that disturbance severity, vegetation structure and plant productivity vary between upland and lowland forest stands. Future changes in boreal vegetation dynamics are predicted to have consequences for a range of ecosystem services including climate feedbacks and wildlife management. Here, as part of a broader study on habitat use and forage of woodland caribou, we investigated the effects of soil drainage class (upland vs. lowland), disturbance (wildfire vs. timber harvest), and stand age on understory plant species richness, cover, biomass, productivity, and foliar C/N. Due to faster nutrient turnover rates in upland soils, we predicted that understory vegetation in uplands would be more productive, biodiverse and nutrient-rich than in lowlands. We also expected disturbance to lead to greater changes in understory vegetation in uplands, given that both fire and timber harvesting tend to be more severe in drier ecosystems. Our results showed that plant understory characteristics varied primarily between soil drainage classes, with few differences between stands recovering from wildfire or timber harvesting. Contrary to our predictions, lowland understory vegetation had greater total understory plant species richness, aboveground net primary productivity, and foliar C/N compared to upland understory vegetation. We also found no difference in total understory vegetation percent cover, productivity or foliar C/N between burned and harvested stands. Understory net primary productivity decreased with time following disturbance in uplands but increased nonlinearly with stand age in lowlands. Greater productivity in lowlands was attributed primarily to evergreen shrubs, though graminoids also were more productive in lowlands than in uplands. Our study has implications for the threatened woodland caribou with respect to the nutritional aspects of their habitat selection. Our results suggest that the commonly held assertion that, by selecting lowlands, caribou face a trade-off between lower predation risk and lower forage quality may be incorrect and requires further examination. [ABSTRACT FROM AUTHOR]

Ecotypes offer an essential framework for conservation and ecological understanding, but their identification can be problematic. These challenges are exemplified by the sedentary and migratory ecotypes of woodland caribou ( Rangifer tarandus caribou ). In Ontario, Canada, reliable discrimination based on morphology, pelage, or genetics has been unsuccessful. We tested the discriminatory power of locational and movement metrics as candidate indicators of discrete behaviours for 132 GPS-tracked female caribou. We assigned each animal to an ecotype each year using two variables which demonstrated the strongest bi-modality and the best discriminatory power: percent of calving season locations within the Hudson Bay Lowland and mean distance to treeline during calving season. The analysis revealed two distinct modes. None of 101 caribou tracked for more than 1 year switched behaviours, implying the distinction may be permanent. Although there was no significant difference in morphology between ecotypes, mean aggregation metrics and calving dates were significantly different. Geographic distribution of these ecotypes showed substantial range overlap, particularly during winter, which presents challenges for conservation of the sedentary ecotype, a threatened designatable unit under federal and provincial legislation. Woodland caribou − with its cryptic ecotypes, discernible from differences in spatial behaviour − illustrate the importance of this type of analysis for identifying significant units for protection, understanding habitat relationships, and delineating ranges for habitat protection. [ABSTRACT FROM AUTHOR]

Large-scale conservation planning entails the establishment of protected area networks that retain substantive natural habitat, biodiversity, and functional connectivity, but developing such networks at the spatial extent needed for meeting global targets involves considerable logistical, political, and social challenges. Normally, governments oversee development of protected area networks, but in the absence of political leadership private initiatives may offer a reasonable alternative approach in conservation planning. We review the Canadian Boreal Forest Agreement (CBFA), a private conservation planning initiative established by forestry companies and environmental organizations that suspends permitted logging activities on roughly 29 million hectares of boreal forest in Canada. The CBFA is touted as a milestone in conservation planning, multi-stakeholder cooperation, and woodland caribou conservation. Yet, the CBFA: 1) involves public land but excludes federal, provincial and aboriginal governments; 2) is not legally binding or necessarily transferrable upon sale of forest tenures; and 3) exempts industrial activities other than logging. Covering 4.6% of the boreal region of Canada, CBFA land tenures do not include most boreal ecozones and do not conform to standard guidelines for designing effective protected area networks. Further, the CBFA does not anticipate effects of climate change, which by 2080 likely will render land tenures unsuitable for caribou, the flagship species of the agreement. We conclude that private initiatives like the CBFA may constitute positive, initial steps toward large-scale conservation planning, but their successful integration into protected area networks will require scientifically robust and transparent efforts that are more fully coordinated with public initiatives. [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]

The long-term persistence of boreal caribou (Rangifer tarandus caribou) is threatened by the negative impacts of human activities, including industrial development. The vast geographical distribution and behavioural variability of caribou warranted the development and validation of an appropriate conservation tool for managers in eastern Canada. We developed a habitat suitability model for boreal caribou in Québec by integrating expert knowledge into a hierarchical analysis. We elicited responses from 14 experts on caribou ecology to determine the best spatiotemporal scales of application, the relative importance of habitat variables, the zone of influence of human infrastructure, and the parameterization of the model. Based on this input, we built the model using 8 habitat categories and 3 human infrastructure variables. Experts identified mature conifer-dominated forests and open lichen woodlands as the most important vegetation categories for boreal caribou, whereas density of and proximity to paved roads, forest roads, and mines decreased habitat quality. We mapped the resulting model over the entire province of Québec (up to the northern forest allocation limit), and validated it using independent GPS telemetry datasets acquired in 3 distinct regions. Our model predicted that habitat suitability was highest in the northeastern part of our study area, where timber harvest activities and roads were virtually absent. Conversely, southern parts of Québec were generally unsuitable for boreal caribou. Our habitat suitability model is among the first tools for boreal caribou conservation available to wildlife and land managers in Québec. [ABSTRACT FROM AUTHOR]

Highlights: [•] We model caribou use based on timber harvesting, roads, predators and apparent competitors. [•] Increases in roads and wolves result in a decrease in caribou use at the broad scale (>10,000ha). [•] Increases in moose and moose browse result in a decrease in caribou use at the fine scale (<1000ha). [•] The relationship between logging roads and moose browse and decreases in caribou use are indirect. [•] Forest overstorey and age, alone, are not strong predictors of caribou use. [Copyright &y& Elsevier]

Highlights: [•] We studied cumulative disturbance effect on female boreal caribou home-range size. [•] Roads and clearcuts had a significant impact on female home-range size. [•] Females expanded before contracting home-ranges as disturbance levels increased. [•] Females are seemingly constrained to suboptimal habitats at high disturbance levels. [•] Caribou seem to have limited natural capacity to cope with cumulative disturbances. [ABSTRACT FROM AUTHOR]

Highlights: [•] We examined lichen growth during 15months for three Cladonia species in boreal forests. [•] We compared lichen growth between unharvested control plots, partial cut plots, and clearcut plots. [•] Growth rates of Cladonia stellaris and C. rangiferina were lower in controls than in partial cuts and clearcuts. [•] Lichen cover of the three Cladonia species did not differed between partial cut plots and control plots. [ABSTRACT FROM AUTHOR]

Abstract: Habitat selection and preferences are driven by population limiting factors which can vary across spatial and temporal scales. For example, woodland caribou prefer coniferous forests to avoid predation at the coarse-scale and at finer scales select for forage within forests. Forestry reduces the benefits of forests and prevents the regeneration of adequate caribou habitat. We described Newfoundland woodland caribou habitat preferences across coarse and fine spatial scales and assessed whether cutovers regenerate into forests of similar value to those preferred by the caribou. We determined if caribou preferred coniferous forests at the coarse-scale and which stand characteristics were selected within coniferous stands at the fine-scale. Linear regression was used to determine which stand characteristics predicted the intensity of use of the coniferous forests by the caribou. The same stand characteristics were used to compare cutovers of various ages to coniferous forests using principal component analyses to determine if they share similar characteristics. We found at the coarse-scale that coniferous forests were most preferred but did not differ from cutovers, and at the fine-scale caribou used coniferous forests with more forage. Cutovers did not develop into forests with similar stand characteristics as the coniferous forests selected by the caribou; the canopy of the cutovers was more closed and supported less forage than the coniferous forests. Old cutovers (>40years) foster less forage for caribou and may act as a refuge from predation. This may cause caribou to seek forage in more risky landscapes in order to meet dietary requirements. [Copyright &y& Elsevier]

Abstract: Woodland caribou (Rangifer tarandus caribou) populations are declining worldwide, and predation is considered their most important limiting factor in North America. Caribou are known to reduce predation risk by spacing themselves away from predators and alternative prey. This strategy is now compromised by forestry activities that reduce the amount of suitable caribou habitat and trigger an increase in densities of alternative prey and predators. Our objective was to investigate the influence of predation risk and food availability on selection of a calving location by woodland caribou at three different spatial scales (from coarse to fine: annual home range, calving home range, and forest stand scales) in the boreal forest of Québec, Canada. Using GPS telemetry, we identified calving locations and assessed those using Resource Selection Functions. We determined habitat characteristics using digital ecoforest and topographic maps at the annual and calving home range scales, and with vegetation surveys at the forest stand scale. Caribou selected calving locations located at relatively high elevation and where road density was low, both at the annual and calving home range scales. Within the annual home range scale, they also selected calving locations where the proportion of young and old cutovers was lower than in random areas of similar size. At the forest stand scale, females calved away from roads and young cutovers, using stands where the basal area of black spruce and balsam fir trees was low. At this fine scale, females still selected calving locations located at a relatively high elevation and where the availability of food resources was lower than in random areas located within the same habitat type. The selection of a calving location was driven by predation risk from the largest to the finest spatial scale. Therefore, our results suggest that females may not be able to lower predation risk at larger scales, despite general avoidance of roads and cutovers. We recommend amalgamating all forestry activities within intensive management zones in order to spatially isolate large patches of suitable calving habitat from anthropogenic disturbances. If not possible, we recommend concentrating forestry activities in low-lying areas since caribou consistently selected for relatively high elevations at all scales. [Copyright &y& Elsevier]

Abstract: Alberta woodland caribou (Rangifer tarandus) are classified as threatened in Canada, and a local population in the west-central region, the Little Smoky herd, is at immediate risk of extirpation due, in part, to anthropogenic activities such as oil, gas, and forestry that have altered the ecosystem dynamics. To investigate these impacts, we have developed a spatially explicit, agent-based model (ABM) to simulate winter habitat selection and use of woodland caribou, and to determine the relative impacts of different industrial features on caribou habitat-selection strategies. The ABM model is composed of cognitive caribou agents possessing memory and decision-making heuristics that act to optimize tradeoffs between energy acquisition and disturbance. A set of environmental data layers was used to develop a virtual grid representing the landscape over which caribou move. This grid contained forage-availability, energy-content, and predation-risk values. The model was calibrated using GPS data from caribou radio collars (n = 13) deployed over six months from 2004 to 2005, representing caribou winter activities. Additional simulations were conducted on caribou habitat-selection strategies by assigning industrial features (i.e., roads, seismic lines, pipelines, well sites, cutblocks and burns) different levels of disturbance depending on their type, age, and density. Differences in disturbance effects between industry features were confirmed by verifying which resultant simulations of caribou movement patterns most closely match actual caribou distributions and other patterns extracted from the GPS data. The results elucidate the degree to which caribou perceive different industry features as disturbance, and the differential energetic costs associated with each, thus offering insight into why caribou are choosing the habitats they use, and consequently, the level and type of industry most likely to affect their bioenergetics and fitness. [Copyright &y& Elsevier]

Abstract: Understanding the impact of indirect habitat loss resulting from avoidance of human infrastructure is an important conservation priority. We evaluated resource selection for 10 global positioning system collared northern mountain woodland caribou (Rangifer tarandus caribou) in British Columbia, Canada, with seasonal resource selection functions (RSF) developed at the second-order (landscape) and third-order (within home range) scales. To estimate how much habitat was lost due to avoidance, we estimated the zone of influence (ZOI) around multiple developments and modeled realized and potential habitat. Potential habitat was approximated by removing the ZOI from RSF models. By calculating the spatial difference between potential and realized habitat we estimated the amount of indirect habitat loss. Caribou displayed hierarchical avoidance of development, with the greatest avoidance occurring at the second-order. During both seasons caribou avoided high-use roads by 2km and low-use roads by 1km. In winter, caribou avoided town by 9km compared to 3km in summer. However, in summer caribou avoided mines by 2km and cabins and camps by 1.5km, while in winter when human activity was low, avoidance of these features was minor. As a result of avoidance of the cumulative ZOI, approximately 8% and 2% of high quality habitat was lost in the study area in winter and summer, respectively. Our study provides an approach to identify the extent and quality of habitat influenced by indirect avoidance. Conservation efforts should prioritize protecting areas of high quality habitat degraded by avoidance in the vicinity of human development. [Copyright &y& Elsevier]

Abstract: Natural disturbance emulation has emerged as a key management approach to maintaining biodiversity in logged boreal forests. Forest managers’ success in emulating understory forest ecosystem functions, e.g., for the provision of habitat even for large mammals, has not been tested due, in many cases, to incomplete records of silviculture. We examined regenerating areas of previously conifer-dominated forests in northwestern Ontario, Canada, 10 and 30years after logging and 10 and 30years after fire to test if understory development and moose (Alces alces) forage abundance differed between the two disturbance types and artificial or natural regeneration approaches. In addition, we counted moose pellet groups as a measure of moose use of the region. Specific treatments included: (1) naturally regenerating, fire-origin forests, (2) post-harvest, regenerating forests with natural establishment of trees, and (3) post-harvest, regenerating forests with mechanical or chemical site preparation and planting and/or herbicide spraying. We hypothesized that the understory in post-harvest stands would support higher forage availability for moose compared to similarly-aged, fire-origin stands. Abundance of hardwoods, shrubs, and herbaceous plants was greater in naturally-regenerated post-harvest stands than in fire-origin and artificially regenerated post-harvest stands at both 10 and 30years post-disturbance. However, post-harvest, naturally regenerating stands were not significantly associated with higher moose use, rather evidence of moose use increased as a function of the amount of naturally regenerating logged forest in the surrounding landscape. This study suggests that, relative to fire, the intensity of post-harvest silviculture influences habitat suitability for moose. The effect likely cascades to other ungulates, such as woodland caribou (Rangifer tarandus caribou), and vegetation management needs to be considered at scales greater than the stand level in order to achieve habitat management for large mammals. [Copyright &y& Elsevier]

Interest in the response of moose to climate change has increased because of the potential role they play in the conservation of woodland caribou, and threatened loss to recreational and economic opportunities. The objective of this study is to develop a plausible, parsimonious, systems-level model of moose population dynamics that will be useful in exploring the response of moose populations to climate projections. The study begins with a statistical model of moose carrying capacity, which is then integrated into a systems-level model that predicts moose density based on explicit causal factors. Scenario analysis was conducted using a variety of assumptions concerning biotic and abiotic interactions, and under the A2 climate scenario all model scenarios predict a decline of moose density at the southern limits of the Ontario distribution and an increase at the northern extents. Predicted declines are a result of lower carrying capacity and higher heat stress, parasite loads and wolf predation. Given the sensitivity of the model to density-dependent factors, the indirect effect of parasites on decreased recruitment may have greater impact on moose than the direct effect of increased death rate. Results indicate that conservation planning for woodland caribou populations should account for possible increases in moose and wolf populations. [Copyright &y& Elsevier]

Abstract: Conservation of forest-dwelling caribou (Rangifer tarandus caribou) is of great concern across most of its range. Anthropogenic disturbances, primarily logging activities, have been identified as the most important cause of caribou decline, although the mechanisms underlying this decline are not fully understood. Caribou commonly display fidelity to calving sites or seasonal ranges, but the potential role of this life-history trait has been largely overlooked in research and conservation planning. This is surprising because sites and ranges with high inter-annual use should have high conservation value. We investigated the relationship between habitat disturbances and home-range fidelity of forest-dwelling caribou across three study sites in Québec, Canada, using a broad range of natural and anthropogenic disturbances. Between 2004 and 2007, we tracked 47 adult female caribou using GPS collars. Home-range fidelity varied between seasons, being higher during calving and summer, and lower during winter. Caribou reduced fidelity following natural and anthropogenic disturbances, the latter having a stronger negative influence. Anthropogenic disturbances had a strong negative impact on home-range fidelity during annual, summer and winter periods, whereas natural disturbance was the dominant factor during calving. Despite this negative influence on fidelity, caribou tended to demonstrate range fidelity even in study sites most impacted by human activities. Habitat disturbances could produce two possible outcomes for caribou conservation: (1) a trend for females to reduce home-range fidelity which could translate into lower calf and female caribou survival through reduced familiarity with food distribution, escape cover and predation risk and (2) a global tendency to maintain range fidelity even in a drastically modified landscape which could turn into an ecological trap, particularly for calves when predation risk increases due to increased black bear density in early successional forests. Taking range fidelity behavior into consideration during forest management planning could direct conservation efforts toward the best available sites and therefore facilitate caribou persistence in managed landscapes. [Copyright &y& Elsevier]

Abstract: Prioritization of conservation efforts for threatened and endangered species has tended to focus on factors measuring the risk of extirpation rather than the probability of success and cost. Approaches such as triage are advisable when three main conditions are present: insufficient capacity exists to adequately treat all patients, patients are in a critical state and cannot wait until additional capacity becomes available, and patients differ in their likely outcome and/or the amount of treatment they require. The objective of our study was to document the status of woodland caribou (Rangifer tarandus) herds in Alberta, Canada, with respect to these three conditions and to determine whether a triage approach might be warranted. To do this we modeled three types of recovery effort – protection, habitat restoration, and wolf control – and estimated the opportunity cost of recovery for each herd. We also assessed herds with respect to a suite of factors linked to long-term viability. We found that all but three herds will decline to critical levels (<10 animals) within approximately 30years if current population trends continue. The opportunity cost of protecting all ranges by excluding new development, in terms of the net present value of petroleum and forestry resources, was estimated to be in excess of 100 billion dollars (assuming no substitution of activity outside of the ranges). A habitat restoration program applied to all ranges would cost several hundred million dollars, and a provincial-scale wolf control program would cost tens of millions of dollars. Recovery costs among herds varied by an order of magnitude. Herds also varied substantially in terms of their potential viability. These findings suggest that woodland caribou in Alberta meet the conditions whereby triage should be considered as an appropriate conservation strategy. [Copyright &y& Elsevier]

Abstract: Habitat alteration caused by forest harvesting seems to contribute to the decline of forest-dwelling caribou, an ecotype of woodland caribou (Rangifer tarandus caribou) inhabiting the boreal ecosystem. To serve as basework to the establishment of conservation measures for the species, we have studied the hierarchical habitat selection of forest-dwelling caribou in a boreal landscape of Québec strongly impacted by logging. Fifteen females were surveyed by GPS telemetry between April 2004 and March 2006. Home ranges showed a high proportion of 90–120 year-old forests, a low proportion of regenerating forests (20–40 years old) and a tendency to include a greater proportion of 6–20 year-old clearcuts in relation to their availability in the study area. At the home range scale, selection patterns differed between periods, possibly reflecting specific requirements linked to caribou life cycle. Caribou selected open lichen woodlands throughout the year while mature closed forests (≥50 years) were selected uniquely during summer. The 6–20 year-old clearcuts were avoided during calving, in summer and during the rutting period but were selected during spring. Our results indicate that mature forest and open lichen woodlands are highly selected forest cover types by caribou at both spatial scales. Although clearcuts were generally avoided at the home range scale, such avoidance was not observed at the larger scale, the search for 90–120 year-old forests being hampered by a uniform distribution of clearcuts. An a posteriori landscape analysis highlighted the spatial association between 6–20 year-old clearcuts and 90–120 year-old forests, an association that can be explained by the current regulations used in Québec. Our results underline the importance of pursuing research concerning the impact of such an exploitation regime on the long-term maintenance of the forest caribou in the boreal landscape. [Copyright &y& Elsevier]

As global conservation actions become more urgent, informed decision-making requires robust analyses of the costs and benefits of policy options, based on available evidence. Recovery planning for threatened or endangered species must assume a cause-and-effect relationship between proposed management interventions and population responses. However, a significant portion of current knowledge about threatened or endangered species is derived from observational studies because experiments that fully meet random and controlled design criteria are largely infeasible or unethical. Large-scale field experiments are becoming more common, yet the greater uncertainty generated by what remain fundamentally observational studies can lead researchers to weak inferences about causal mechanisms, creating debate and confusion among decision-makers, planners and stakeholders. This has been an acute problem facing conservationists and governments as they struggle with the successful recovery of species in decline. In other domains where experimental evidence is difficult to collect, causal modelling has been adopted to identify causal relationships from observational data, based on a set of strong assumptions and identification rules. In Canada, significant and ongoing efforts have had limited success in reversing the population decline of woodland caribou (Rangifer tarandus caribou). We examine the scientific framework for woodland caribou recovery efforts through the lens of causal modelling, highlighting feasible steps that could be taken to improve the rigour of causal inferences. • Policy decisions require strong cause-effect inferences to predict success of interventions. • Causal inferences about woodland caribou declines are constrained by observational data. • Causal modelling improves inferences for policy decisions in fields similarly constrained. • Policy interventions to arrest caribou declines can benefit from insights from causal modelling. [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]

A dynamic model on 137Cs in reindeer is presented, taking into consideration short- and long-term mechanisms, including the effect of ground deposition, transfer to vegetation, reindeer diet, feed intake, absorption and depletion of radiocaesium in the reindeer body. The model was optimised to fit measured activity concentrations in Swedish reindeer after the Chernobyl fallout. For comparison, regression analyses were made and aggregated transfer factors and effective ecological half-lives were estimated. The fit of the simulated model to observed activity concentrations was slightly better than the fit obtained by linear regressions. Improved knowledge about radiocaesium in vegetation would make the model more accurate for predictive purposes. Presently, the use of Tag and T eff is probably better for predictions, provided that their temporal and geographical limitations are taken into consideration. The dynamic model describes mechanisms better and may explain how changes in the system influence on activity concentrations of radiocaesium in the animal. [Copyright &y& Elsevier]

Abstract: Conservation of remaining woodland caribou (Rangifer tarandus caribou) populations requires land management strategies that not only maintain caribou habitat, but also favour habitat connectivity. This study presents and field tests graph theory-based measures of landscape connectivity, and demonstrate an association between the distribution of woodland caribou and well-connected winter habitat. Cost values for the intervening land cover types were determined based on the probability of selection relative to high-quality winter habitat. Habitat connectivity was then represented by linking high-quality habitat patches along least-cost paths through this parameterized cost surface. A randomization procedure was used to assess the animal’s association with habitat connected at increasing distance thresholds to identify appropriate scales of response. A strong relationship was obtained between large clusters of high-quality winter habitat patches and winter GPS telemetry location points (November 1–March 15) from two woodland caribou herds in Manitoba, Canada. This relationship was stronger when only late winter location points (January 1–March 15) were used. Our results highlight the importance of accounting for the spatial configuration of habitat on the landscape and the intervening land cover types when assessing range quality for woodland caribou. They also provide support for the use of graph theory to assist in identifying core activity areas for woodland caribou and key linkages between these areas and other parts of the landscape. [Copyright &y& Elsevier]

Abstract: Serum samples from 25 reindeer (Rangifer tarandus tarandus) were assayed for antibody against hypodermin C (HyC) using an ELISA. Nineteen animals were calves (born in 1998, 1999 or 2001) and six were adults (3–10 years old at first blood collection). The samples were collected over periods of 4 months (calves born in 2001) or 27 months (adults and calves born in 1998 and 1999), the latter encompassing three Hypoderma tarandi infestation seasons. The calves received antibodies against HyC from their mothers, either by placental transfer or through the ingestion of colostrum. The low level at 3h postpartum compared to the high level 3 days after birth in one calf suggests that the antibodies are transferred through colostrum. The levels of antibody of maternal origin decreased rapidly and reached low levels by mid-July, which coincides with the onset of the major Hypoderma ovipositioning season in this region. The calves thus did not appear to be protected by antibody against HyC when they were exposed to H. tarandi infestation for the first time. Antibody levels increased following infestation and reached a maximum during November or December, which coincides with when the H. tarandi larva stops migrating after it has reached the site under the skin of the back of the host and develops further. Levels declined thereafter and reached a nadir during the following summer. After the subsequent re-infestation, the increase in levels occurred at least 1 month earlier than with the first infestation. Levels remained elevated throughout the year after repeated infestations. This implies that the antibodies persist after the annual exit of mature larvae from the animal, and after larvae have been killed by application of ivermectin. Levels in adults, however, declined significantly with age, and levels were significantly lower in animals that were 4–11 years old than in 1-year-old animals during the same 1-year period. This supports the contention that the functional capacity of the immune system declines gradually with age. The study demonstrated that HyC is potentially useful for serological diagnosis of hypodermosis in reindeer, but the persistence of antibodies complicates interpretation of antibody-based surveillance programme data in all cases other than first-time exposure. [Copyright &y& Elsevier]

Besnoitia tarandi tissue cysts were found in naturally-infected reindeer (Rangifer tarandus) from Finland. Infectivity of its tissue cysts, bradyzoites, and tachyzoites to animals and cell culture was studied. The bradyzoites and tissue cysts were not infectious to out-bred mice, rabbits or gerbils. When fed tissue cysts, neither cats nor dogs excreted oocysts. However, the parasite was lethal to interferon-gamma gene knock out mice irrespective of the route of inoculation. The parasite was grown successfully in African Green Monkey cells from tissues of two reindeer for the first time. Non-dividing, uninucleate tachyzoites from smears from cell cultures were 5.6×1.4μm (4.5–7.4×1.0–1.9, n=50) in size. Longitudinally-cut bradyzoites in tissue sections measured 7.4×1.3μm (6.5–7.8×1.0–1.6, n=30). Ultrastructurally, tachyzoites and bradyzoites were similar to those in other Besnoitia species, and in particular to parasites described from cattle (Besnoitia besnoiti) and equids (Besnoitia bennetti) in that their bradyzoites lacked enigmatic bodies. Based on comparative analysis of three portions of nuclear ribosomal DNA (the small and large subunits and the first internal transcribed spacer) B. tarandi was found to be more closely related to the other congeners described from ungulates. The parasite was formally redescribed and specimens deposited in the US National Parasite Collection. [Copyright &y& Elsevier]

The decline in woodland caribou (Rangifer tarandus caribou) populations in Alberta lead to classification as a threatened species. Rapid industrial development continues to affect caribou habitat. Natural and anthropogenic factors, which affect population dynamics, act cumulatively. We developed an interactive cumulative effects model, which could be used to assess both natural and anthropogenic factors influencing survival of caribou. This model is based on functional and numerical responses of carnivores (wolves (Canis lupus)), herbivores (caribou and moose (Alces alces)) and resources (lichen and vascular plants). It includes stochasticity in some elements and is aspatial (but divides habitat into categories depending on habitat type and age). Based on simulation experiments, we suggest that the most detrimental factor on caribou population dynamics is the functional loss of habitat due to avoidance of good quality habitat in proximity of industrial infrastructures. We argue that in the natural boreal ecosystem, habitat was not limiting caribou in northern Alberta, and caribou could coexist with uncontrolled wolf populations that kept caribou at low densities of about 0.1 km-2. We argue that wolf control is not a practical solution in caribou conservation and propose different alternatives. We also suggest potential thresholds for industrial development for specific interactions of different predation pressures and habitat carrying capacity. [Copyright &y& Elsevier]

In the studies reported here, the micronucleus assay, a common cytogenetic technique, was used to examine the dose–responses in fibroblasts from three ungulate species (white-tailed deer, woodland caribou, and Indian muntjac) exposed to high doses of ionizing radiation (1–4 Gy of 60Co gamma radiation). This assay was also used to examine the effects of exposure to low doses (1–100 mGy) typical of what these species experience in a year from natural and anthropogenic environmental sources. An adaptive response, defined as the induction of resistance to a stressor by a prior exposure to a small “adapting” stress, was observed after exposure to low doses. This work indicates that very small doses are protective for the endpoint examined. The same level of protection was seen at all adapting doses, including 1 radiation track per cell, the lowest possible cellular dose. These results are consistent with other studies in a wide variety of organisms that demonstrate a protective effect of low doses at both cellular and whole-organism levels. This implies that environmental regulations predicated on the idea that even the smallest dose of radiation carries a quantifiable risk of direct adverse consequences to the exposed organism require further examination. Cytogenetic assays provide affordable and feasible biological effects-based alternatives that are more biologically relevant than traditional contaminant concentration-based radioecological risk assessment. [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]

How to mitigate the impacts of anthropogenic habitat alteration and restore ecological processes has become an imperative question facing applied ecology. One high-profile example in Canada is boreal woodland caribou, which are declining across North America largely due to anthropogenic habitat alteration and associated changes to predator-prey dynamics. Habitat restoration is increasingly being implemented to recover habitat, as is mandated by federal law. But given the extent of the disturbance and the cost to conduct restoration, evaluating the effectiveness of restoration treatments is needed for effective recovery of caribou populations. We evaluated the effectiveness of silvicultural treatments to reduce predator (wolf and bear) and prey (moose and caribou) use of linear features using a multiple lines of evidence approach. All four species were less likely to be present at treated sites than untreated sites, and daily photo capture rates of moose and wolves when present at treated sites also declined; though effect sizes were typically small. Complimenting the camera-based results, individual moose, bears, and wolves monitored with GPS collars also showed a decline in the use of treated linear features, particularly those with higher intensity treatments, though the response was non-significant. The reduction in the use of treated lines did not scale-up into a significant decline in overall line-use within the treatment area. While we found more evidence than not supporting that animals reduced use of the restoration sites, our study highlights the complexity of monitoring and evaluating the success of habitat restoration. Understanding long-term responses is imperative to ensure habitat restoration is effective. [ABSTRACT FROM AUTHOR]

• Context for pipeline corridors as potential ecological sinks for wildlife populations. • Quantitative analysis of plant taxa foraged by woodland caribou and grizzly bear. • Species composition and cover varied between pipelines versus adjacent forest. • High cover of graminoids on pipeline corridors as compared to adjacent forest. • Prioritizing ecosites within caribou ranges may be a beneficial restoration strategy. The construction of pipeline rights-of-way (ROWs, hereafter 'pipeline') involves mechanical site clearing, which impacts soil and ground cover vegetation and has implications for forage availability and predation risk for threatened wildlife, including woodland caribou (Rangifer tarandus) and grizzly bear (Ursus arctos). However, there has been no quantitative evaluation of vegetation communities on open pipelines as compared to the adjacent intact forest. We compared the cover of ground vegetation by vegetation type, and the cover and composition for plant taxa known for their importance as woodland caribou and grizzly bear forage, between plots located on pipeline corridors, near the edge of the pipeline corridor, and in the adjacent undisturbed forest across six different boreal forest ecosite types in west-central and north-western Alberta, Canada. Pipeline corridors were characterized by higher total ground vegetation cover, and cover of low shrubs, lichens, bryophyte and of targeted forage species of low shrubs, bryophytes, and lichens. In contrast, pipelines had higher graminoid cover and cover of target forage species of tall shrubs and graminoids, as compared to adjacent forest. Despite the substantive differences in cover and composition of ground vegetation among the ecosite types, differences between pipelines and the adjacent forest were quite consistent, with a few exceptions. For instance, forb cover was higher in the adjacent forest compared with pipelines in shrubby ecosite types, but was similar across plot locations in other ecosites. Species composition also varied among ecosites and differed between the adjacent forest and on pipelines; with pipelines dominated by graminoids, particularly Carex species. Our results demonstrate that pipelines influence ground vegetation communities, and cover and composition of wildlife forage species, across the boreal forest landscapes of Alberta; we suggest this results in pipelines being a potential ecological sink for wildlife populations, including threatened caribou. To ensure pipelines can recover, restoration strategies that promote natural recovery or purposeful re-planting may be required to accelerate forest re-establishment and put inactive pipeline corridors within caribou ranges on a recovery trajectory. Our results suggest that ecosites can be used to prioritize pipelines where restoration or management actions may be the most beneficial. [ABSTRACT FROM AUTHOR]