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We investigated whether woodland caribou (Rangifer tarandus caribou) would remain in a 2772 km2 area in eastern Quebec where the forest management plan included the preservation of large forest blocks (35–182 km2) linked with >400 m wide corridors and where cuts were amalgamated in large zones. To evaluate changes in caribou abundance and habitat selection, we conducted five aerial surveys and followed by telemetry 13 to 22 female caribou each year, from March 1998 to March 2005. Caribou numbers declined by 59% between 1999 and 2001 but gradually recovered to initial abundance. Female survival increased from 73.3% in 1999 to 87.3%–93.4% in 2004 and 2005. Caribou selected protected blocks, used corridors in proportion to their availability, and avoided logged areas. They preferred closed conifer stands without terrestrial lichens and open conifer stands with or without terrestrial lichens throughout the study. Open habitats (clearcuts and burns), regenerating sites, mixed and deciduous stands, and water bodies were avoided. The main zones used by caribou gradually shifted towards the southwest of the study area, likely as a result of disturbance and habitat loss due to logging of mature conifers in the east. We conclude that caribou numbers were maintained within the managed area as a result of the presence of protected blocks and uncut continuous forest. [ABSTRACT FROM AUTHOR]

Extensive logging of the boreal forest rejuvenates landscapes once dominated by old-growth stands. As black bear (Ursus americanus Pallas, 1780) fitness and behavior are known to be primarily related to the abundance of shade-intolerant soft mast species in northern forests, we hypothesized that logging will influence habitat and space use patterns of black bears. We used VHF telemetry on 12 female black bears in the Réserve faunique des Laurentides (Quebec, Canada) to investigate seasonal patterns of habitat selection in an exploited heterogeneous boreal landscape at different spatial scales. Habitat characterization based on seven forest cover types allowed us to compare the productivity of key forage species in various post-logging age classes. Regenerating stands (6-20 years old) had the uppermost ground vegetation cover, providing both the highest density and a high biomass of berries. Black bears preferred regenerating stands (6-20 years old) and avoided mature coniferous forests inside their home range. Home-range size was inversely related to the proportion of regenerating stands (6-20 years old). Intensive logging influenced black bear habitat and space use patterns, and presumably their population dynamics. An increase in the habitat quality of an opportunistic predator poses great concern for conservation, especially for forest-dwelling woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)). [ABSTRACT FROM AUTHOR]

1. Understanding animal–habitat relationships is central to the development of strategies for wildlife management and conservation. The availability of habitat attributes often changes along latitudinal and longitudinal axes, and animals may respond to those changes by adjusting their selection. We evaluated whether landscape selection by forest-dwelling woodland caribou Rangifer tarandus caribou varied along geographical gradients in habitat attributes. 2. Centroids ( n = 422) of track networks made by caribou in winter were recorded during aerial surveys conducted over 161 920 km2 of boreal forest in Québec, Canada. Autologistic models were estimated by comparing the characteristics of landscapes (201 km2) centred on each centroid to an equal number of randomly located landscapes, with an autocovariate controlling for the non-independence among caribou locations. 3. The availability of habitat attributes varied along longitudinal and latitudinal gradients, and caribou altered their landscape selection with respect to those gradients. 4. Information Theory provided substantial support for only one model. The model revealed that the probability of occurrence of caribou increased with the abundance of conifer forests over most of the study region, but this positive response gradually became negative towards the southern portion of the region. The association between caribou and lichens changed from being negative west of the study region to being positive in the eastern part. Availability of landscapes dominated by lichen decreased from west to east. Finally, caribou generally displayed an aversion to areas with high road density, a negative association that became positive in the southern part of the study region. 5. Synthesis and applications. Under current legislation in Canada, the critical habitat of woodland caribou must be defined, and then protected. Our autoregressive models can help to identify landscapes to prioritize conservation efforts. The probability of occurrence of caribou was related to different landscape characteristics across their range, which implies that the typical habitat of woodland caribou differs spatially. Such behavioural plasticity could be problematic for defining critical habitat, but we showed that spatial variation in landscape selection was organized along geographical gradients. Our study illustrates how geographical trends in habitat selection can guide management and conservation decisions. [ABSTRACT FROM AUTHOR]

Limiting factors of caribou (Rangifer tarandus) populations vary regionally. In tundra environments, this species appears to be regulated by food, either because wolves (Canis lupus) are absent or because migration of caribou allows escape from predation during part of the year. In the boreal forest, the main limiting factors are hunting and predation but because of low caribou densities, no regulation mechanism seems to exist between caribou and wolves. Moose (AIces alces) is the primary prey species of wolves and consequently, if moose abundance increases, wolves should also increase, independently of the caribou population. Thus, caribou could experience high predation rates and be eliminated in high wolf densities. Here we attempted to identify the necessary conditions to maintain caribou numbers in the presence of moose. To do so, we built a deterministic model that simulated the relationship between a caribou population regulated by food competition and limited by predation, a moose population regulated by predation, and a wolf population, the abundance of which is determined by moose abundance. At current hunting rates for caribou and moose in the boreal forest, and in the absence of wolf trapping, the model predicted that the caribou population would be extirpated in approximately 100 years. Wolf trapping was not adequate to conserve the caribou population unless very intensive control was undertaken. In the absence of trapping, cessation of caribou hunting allowed a 3-fold increase in caribou numbers over the long term, if the moose population remained low. According to our model, the best management measure for caribou consisted of maintaining a low moose density through appropriate population and habitat management strategies, which prevented expansion of the wolf population and limited predation on caribou. [ABSTRACT FROM AUTHOR]

Falcipennis canadensis (Spruce Grouse) are a habitat specialist of coniferous forest in North America and typically have large home ranges (≈ 25 ha, range = 22-75 ha). Although this species is sensitive to logging, few studies report abundance and population trends in relation to habitat loss and fragmentation. In early May of 1997 to 1999. we surveyed Spruce Grouse in 21 riparian and 27 upland residual forest strips (width = 51-132 m) located within six clear-cut landscapes (23-256 km²) of southcentral Québec, Canada. We also surveyed five control sites in uncut continuous forest surrounding one landscape. Contrary to our prediction that Spruce Grouse would not be observed from such narrow strips, they were detected in 24 of the 48 strips. Both types of strips had similar occurrence rates and abundance indices (2.01 ± 0.46 [SE] males/10 stations in riparian strips, 1.29 ± 0.35 males/10 stations in upland strips). Because of the age of adjacent cuts (mean = 4.2 years. range = 2-8 years), crowding of grouse that were present at logging time into forest strips does not adequately explain the numbers of Spruce Grouse in these structures. Therefore, we conclude that Spruce Grouse observed in forest strips have either immigrated from outside or were local recruits. Despite persistence of Spruce Grouse in residual forests of logged landscapes, we suggest a cautious approach to forest management since the species' long-term persistence could be jeopardized if residual forest strips are harvested. [ABSTRACT FROM AUTHOR]

We developed a habitat suitability index (HSI) model for moose (Alces alces) in the boreal forest. The model used two components: a suitability index for food (SIfood) and another for the interspersion between cover and food (SIedge). We used forest maps as the input data source, and the value of each stand type in terms of cover and food was based on field surveys. To validate the model, the habitat preference of moose equipped with global positioning system telemetry collars was assessed at both landscape and home-range scales. We expected the habitat-preference index to correlate with suitability indices determined using the global model and each of its two components. Habitat suitability was assessed in evaluation plots of 500, 100, and 10 ha. Unexpectedly, the habitat-preference index correlated better with SIfood and SIedge than with the global model. The suitability indices also performed better when assessed in large plots. Selection of 500 ha plots related mostly to SIedge, but SIfood was more important when smaller evaluation plots were used, especially for males. Females preferred plots with intermediate SIfood values. At the fine scale, SIedge was not as attractive to moose as was previously observed, presumably because snow conditions prevailing in our study area were relatively moderate. We recommend utilizing the model with SIedge in large plots (ca. 500 ha) and SIfood in smaller plots. Our model could be adapted and applied to other areas by using empirical data to adjust the relative value of stand types in terms of cover and food. [ABSTRACT FROM AUTHOR]

We assessed the influence of temporal and spatial changes in food availability on home-range size and movements of moose (Alces alces (L., 1758)). Ten adult moose were radio-collared and monitored with GPS telemetry collars during two contrasting time periods based on food quality and availability: summer (growing period) and winter (dormant and snowy period). According to the habitat productivity – home-range size hypothesis, we expected home-range size and movement rate to be negatively correlated with the proportion of food-rich habitat types in home ranges. Food availability influenced space use, but the effect was more pronounced at the small scale (i.e., movement rates) than at the large scale (i.e., home-range sizes) and during winter than summer. The negative relationship between food availability and home-range size only existed in winter, but movement rates were lower in food-rich habitat types in both time periods. Our results suggested that body size was not the primary factor governing sex-related differences in space use which were likely more related to specific needs of females with regard to the feeding and protection of calves. We suggest that the habitat productivity – home-range size hypothesis may not always be supported when forage is widely distributed and that movement rates can be a better index of forage availability than home-range sizes in such situations. [ABSTRACT FROM AUTHOR]

Winter aerial surveys of moose (Alces alces) were completed on 14 landscapes (10–256 km²) formed of aggregated black spruce (Picea mariana) clear-cuts logged 3–9 years ago in southcentral Québec. Moose were present in 8 landscapes (11 yards) and had a mean density of 0.20 moose/10 km², which was 50% of the density observed in the same hunting zone with a similar forest composition. Based on previous work, effects of variability in hunting pressure and time since cutting were assumed not to influence distribution and abundance of moose. Browse density did not increase with age of cuts. Moose density was not related to the size of the clear-cut landscapes or the proportion of residual forest (18–40%) within each landscape (P = 0.14). Moose yards were not located close to uncut forest surrounding the landscapes and did not have a greater proportion of residual forest than clear-cut landscapes. Moose yards had a denser shrub layer and more browse available than random sites selected in the same landscapes. The presence of moose in large clear-cut black spruce landscapes is related to vegetation characteristics and not the spatial pattern of the forest. The authors propose two strategies to maintain moose populations and moose hunting activity in this type of forest after harvesting. [ABSTRACT FROM AUTHOR]

Habitat selection by moose was studied over 4 years in two large sectors subject to intensive forest harvesting using a two-scale approach. At the coarser scale, i.e. location of the home range within the landscape, habitat selection did not appear to be influenced by the presence of clear-cuts. In one sector, moose preferred mature mixed stands, young coniferous, and mature coniferous stands. In the second sector, the highest preference was noted for cut areas and mature deciduous stands. Moose home ranges were located in areas with higher edge and interspersion among habitat patches. Home range size for females was positively related to the proportion of cuts, but movements were not. Habitat selection was more pronounced at the finer scale (animal locations within home range) and did not differ between sectors. Mixed stands were preferred in all seasons. Mature conifer stands were preferred in summer and in early winter while young conifer stands were preferred in late winter. Clear-cuts were avoided except in early winter. Moose were located in areas closer to edge between food and cover stands than were random locations, especially in late winter. A marked decrease in movements also was noted in late winter. This study shows differences in habitat selection pattern between the coarser and finer scales. For example, clear-cuts did not seem to markedly influence home range location at a coarser scale, and adaptations to minimize their impact seemed to operate at a finer scale. Coarser scale habitat selection was probably linked to a trade-off between predator avoidance and browse availability, whereas seasonal changes suggest behavioural adaptations of moose to maximize energy gain and counteract predation and other adverse environmental conditions at the finer scale. [ABSTRACT FROM AUTHOR]

Aerial survey data were used to describe moose density changes in relation to habitat composition and structure in clear-cut areas, and to infer the impact of these variables on limiting factors. We hypothesized that moose density would be lower in cut areas due to increased hunting and predation. Four habitat types (food and cover stands, cover stands, cuts, and other habitats) and 7 fragmentation indices were used in our analyses. Aerial surveys conducted in seven 35–112-km² blocks showed that moose density was related to the proportion of deciduous and mixed (food and cover) stands within each block and edge between food and cover and resinous stands (cover). Density, productivity, and harvest rate were not significantly influenced by clear-cuts. Our results suggest that habitat models should consider food and food-cover border over other habitat components. [ABSTRACT FROM AUTHOR]

Evaluates the reliability of forest maps for describing wildlife habitats. Measurement of lateral cover and deciduous browse availability; Characterization of wildlife habitats; Classification of cover type on forest maps.

Sustainable management of natural ecosystems requires adequate participation of Aboriginal people. This especially includes the joint use of local ecological and scientific knowledge to document natural processes and develop management guidelines. Despite increasing recognition of this principle, endorsed by the international community and several Aboriginal nations, there are very few genuine cases that show significant progress in this discipline. This case is similar in North American forestry where several initiatives have documented Aboriginal land use without ever significantly recognizing local knowledge in the development of forest management guidelines. In the search for innovative solutions on this topic, the Waswanipi Cree Model Forest developed a governance tool that allows Cree land users to translate their needs into management plans. We collaborated on this initiative by developing and testing a participatory approach, allowing the development of moose ( L.) habitat management guidelines, better adapted to the socioecological context of the Cree. This innovative approach increases mutual understanding between Aboriginal and non-Aboriginal managers and favours the social acceptability of the guidelines while contributing to a more sustainable management of this northern and fragile ecosystem. This study will influence stakeholders striving to improve collaborative ecosystem management with Aboriginal people. [ABSTRACT FROM AUTHOR]

Participation of aboriginal people in Canadian forestry is a requirement of sustainable management. We proposed a culturally adapted process to integrate Cree and scientific knowledge in Eeyou Istchee (northern Quebec) that could contribute to a better mutual understanding between Cree and non-Cree, and eventually favour the social acceptability of forest management strategies. We studied moose (Alces alces L.), the Cree featured species and the main forestry issue for the past 40 years. Cree and non-Cree have culturally differing visions for the management of moose habitat. In a previous article, we documented Cree knowledge about moose–habitat relationships. Here, we evaluated some hypotheses built from Cree knowledge by studying the behaviour of moose equipped with GPS collars. In general, results from our habitat use and selection analyses agreed with Cree observations and improved our understanding of moose–habitat relationships in northern Quebec. We jointly demonstrated the importance of mature mixedwoods, balsam fir (Abies balsamea (L.) Mill.) stands, and riparian areas for moose in the northern black spruce (Picea mariana (Mill.) BSP) forest. In these specific areas, management approaches other than clear-cutting should be developed to preserve moose habitat quality. Such an alternative would potentially be more acceptable for the Cree people. [ABSTRACT FROM AUTHOR]

Reduced to small isolated groups by anthropogenic habitat losses or habitat modifications, populations of many endangered species are sensitive to additive sources of mortality, such as predation. Predator control is often one of the first measures considered when predators threaten survival of a population. Unfortunately, predator ecology is often overlooked because relevant data are difficult to obtain. For example, the endangered Gaspésie caribou (Rangifer tarandus caribou) has benefited from 2 periods of predator control that targeted black bears (Ursus americanus) and coyotes (Canis latrans) in an attempt to reduce predation on caribou calves. Despite a high trapping effort, the number of predators removed has remained stable over time. To assess impact of predator movements on efficacy of a control program, we studied space use of 24 black bears and 16 coyotes over 3 years in and around the Gaspésie Conservation Park, Quebec, Canada, using Global Positioning System radiocollars. Annual home ranges of black bears averaged 260 km² and 10 individuals frequented area used by caribou. Annual home ranges of resident coyotes averaged 121 km², whereas dispersing coyotes covered >2,600 km². Coyotes were generally located at lower altitudes than caribou. However, because coyotes undertook long-distance excursions, they overlapped areas used by caribou. Simulations based on observed patterns showed that 314 bears and 102 coyotes potentially shared part of their home range with areas used by female caribou during the calving period. Despite low densities of both predator species, extensive movement and use of nonexclusive territories seem to allow predators to rapidly occupy removal areas, demonstrating the need for recurrent predator removals. Our results underscore the necessity of considering complementary and alternative solutions to predator control to assure long-term protection of endangered species. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor about the article "A Comparison of Distance-Based and Classification-Based Analyses of Habitat Use," by L.M. Conner, M.D. Smith, and L.W. Burger that appeared in a previous issue.

It has been suggested that patterns of habitat selection of animals across spatial scales should reflect the factors limiting individual fitness in a hierarchical fashion. Animals should thus select habitats that permit avoidance of the most important limiting factor at large spatial scales while the influence of less important factors should only be evident at fine scales. We tested this hypothesis by investigating moose Alces alces habitat selection using GPS telemetry in an area where the main factors limiting moose numbers were likely (in order of decreasing importance) predation risk, food availability and snow. At the landscape scale, we predicted that moose would prefer areas where the likelihood of encountering wolves was low or areas where habitats providing protection from predation were dominant. At the home-range scale, we predicted that moose selection would be driven by food availability and snow depth. Wolf territories were delineated using telemetry locations and the study area was divided into 3 sectors that differed in terms of annual snowfall. Vegetation surveys yielded 6 habitat categories that differed with respect to food availability, and shelter from predation or snow. Our results broadly supported the hypothesis because moose reacted to several factors at each scale. At the landscape scale, moose were spatially segregated from wolves by avoiding areas receiving the lowest snowfall, but they also preferentially established their home range in areas where shelter from snow bordered habitat types providing abundant food. At the home-range scale, moose also traded off food availability with avoidance of deep snow and predation risk. During winter, moose increased use of stands providing shelter from snow along edges with stands providing abundant food. Habitat selection patterns of females with calves differed from that of solitary moose, the former being associated primarily with habitats providing protection from predation. Animals should attempt to minimize detrimental effects of the main limiting factors when possible at the large scale. However, when the risk associated with several potential limiting factors varies with scale, we should expect animals to make trade-offs among these. [ABSTRACT FROM AUTHOR]

We studied the response of beaver (Castor canadensis Kuhl), moose (Alces alces L.), and snowshoe hare (Lepus americanus Erxl.) to clear-cutting in three blocks that had been logged 10 years ago. In a previous study, these species had been surveyed in the same blocks 2 years before and 2 years after logging. We also surveyed an uncut block of the initial experimental design that was logged more recently. Over the 10-year period, the shrub layer and available browse have improved markedly in clear-cut areas. As compared with logged coniferous stands, logged mixed stands had higher lateral cover (62% vs. ≍55%) and taller regeneration (>4 m vs. <3 m). Beaver density did not change over the period because its feeding habitat remained unchanged in the riparian forest strips. Moose densities increased 54%–87% in two harvested blocks as a result of both logging and stricter hunting regulations (selective hunting). Based on the rate of increase observed in a control block, we estimate that a 25% density increase in the mixed forest block can be related to logging, while selective hunting can solely be responsible for the change in the coniferous forest block. Snowshoe hare have started to reoccupy logged coniferous stands, but their relative density still remained less than half that of uncut stands. We conclude that, after 10 years, logged mixed stands already offer good habitat conditions for moose and snowshoe hare. Conversely, in logged black spruce (Picea mariana (Mill.) BSP) stands, habitat conditions still remain poor for snowshoe hare because of a lack of cover. [ABSTRACT FROM AUTHOR]

First Nations involvement in forest management is necessary to achieve sustainability, even more in northern Qu6bec where the Cree have constitutional rights on the land. An innovative research approach has been undertaken to improve forest management on Eeyou Astchee, the Cree territory. This project targets moose (Alces alces) because of its importance to the Cree people and because it is a representative species of the northern black spruce ecosystem. The research aims at combining native and scientific knowledge to overcome trust, communication, and cultural barriers, and to build a common vision of moose habitat needs in this northern area. In this poorly known ecosystem, combining Cree and scientific knowledge about moose seems to be a promising avenue to achieve sustainable forest management. Based on new knowledge of this common vision, socioecologicaly-adapted habitat management strategies will be proposed for the study area. The involvement of key stakeholders, and recognition of their knowledge, should promote better support for the research project and better social acceptability of the proposed management recommendations. [ABSTRACT FROM AUTHOR]

Summary 1. It has been hypothesized that a balanced adult sex ratio is necessary for the full participation of ungulate females in reproduction and therefore high productivity. We tested this general hypothesis by combining two complementary approaches. 2. First, using telemetry (n = 60) and annual aerial censuses between 1995 and 1998, we compared two moose Alces alces populations in Quebec, Canada, one non-harvested and the other subject to intensive sport harvesting from the end of September to mid-October. We tested the following predictions for the harvested population: (i) females increase movements and home ranges during the mating period; (ii) the mating system is modified, with the appearance of groups of one male and many females; (iii) subadult males participate in reproduction; (iv) the mating period extends over two to three oestrus cycles; (v) the calving period extends over several months; and (vi) productivity declines. 3. Daily movements and home range sizes during the mating period did not differ between harvested and non-harvested populations. Most groups observed were male–female pairs. Subadult males (1·5–2·5 years old) were only observed with females in the harvested population. Mating and calving periods did not differ between populations. The proportion of females that gave birth and the number of calves produced were also comparable in the two populations. 4. Secondly, we also assessed the existence of a relationship between population productivity and percentage of males in various management units of the province of Quebec that were characterized by a wide range in sex ratios. Contrary to prediction (vi), the number of calves per 100 adult females was not related to the percentage of adult males in the population. 5. The participation of young adult males (subadults) in reproduction in our harvested population may have compensated for the lower percentage of adult males, and thus productivity was unaffected. We therefore reject the hypothesis that intensive harvesting, at least at the level we observed, affects reproduction and population productivity. 6. As there are some uncertainties regarding the long-term effects of high hunting pressure, however, managers should favour sex ratios close to levels observed in non-harvested populations. [ABSTRACT FROM AUTHOR]

Describes moose (Alces alces) disperal pattern, and its role in the maintenance of harvested populations in three regions of Quebec, Canada. Period and extent of natal disperal; Distance between the calf and its mother; Information on the study sites; Results of the study.

Ecological theory predicts that the intensity of antipredator responses is dependent upon the spatiotemporal context of predation risk (the risk allocation hypothesis). However, most studies to date have been conducted over small spatial extents, and did not fully take into account gradual responses to predator proximity. We simultaneously collected spatially explicit data on predator and prey to investigate acute responses of a threatened forest ungulate, the boreal caribou (Rangifer tarandus), to the spatiotemporal dynamics of wolf (Canis lupus) distribution during spring. Movement analysis of GPS-collared individuals from both species revealed high plasticity in habitat-selection decisions of caribou. Female caribou avoided open areas and deciduous forests and moved relatively fast and toward foraging areas when wolves were closer than 2.5 km. Caribou also avoided food-rich areas only when wolves were within 1 km. Our results bridge the gap between long-term perceived risk and immediate flight responses by revealing dynamic antipredator tactics in response to predator proximity. [ABSTRACT FROM AUTHOR]

Habitat selection strategies translate into movement tactics, which reckon with the predator-prey spatial game. Strategic habitat selection analysis can therefore illuminate behavioural games. Cover types at potential encounter sites (i.e. intersections between movement paths of predator and prey) can be compared with cover types available (i) within the area of home-range-overlap ( HRO) between predator and prey; and (ii) along the path ( MP) of each species. Unlike the HRO scale, cover-type availability at MP scale differs between interacting species due to species-specific movement decisions. Scale differences in selection could therefore inform on divergences in fitness rewarding actions between predators and prey., We used this framework to evaluate the spatial game between GPS-collared wolves ( Canis lupus) versus caribou ( Rangifer tarandus), and wolf versus moose ( Alces alces)., Changes in cover-type availability between HRO and MP revealed differences in how each species fine-tuned its movements to habitat features. In contrast to caribou, wolves increased their encounter rate with regenerating cuts along their paths ( MP) relative to the HRO level. As a consequence, wolves were less likely to cross caribou paths in areas with higher percentage of regenerating cuts than expected based on the availability along their paths, whereas caribou had a higher risk of intersecting wolf paths by crossing these areas, relative to random expectation along their paths. Unlike for caribou, availability of mixed and deciduous areas decreased from HRO to MP level for wolves and moose. Overall, wolves displayed stronger similarities in movement decisions with moose than with caribou, thereby revealing the focus of wolves on moose., Our study reveals how differences in fine-scale movement tactics between species create asymmetric relative encounter probabilities between predators and prey, given their paths. Increase in relative risk of encounter for prey and decrease for predators associated with specific cover types emerging from HRO to MP scale analysis can disclose potential weaknesses in current movement tactics involved the predator-prey game, such as caribou use of cutovers in summer-autumn. In turn, these weaknesses can inform on subsequent changes in habitat selection tactics that might arise due to evolutionary forces. [ABSTRACT FROM AUTHOR]

The assessment of disturbance effects on wildlife and resulting mitigation efforts are founded on edge-effect theory. According to the classical view, the abundance of animals affected by human disturbance should increase monotonically with distance from disturbed areas to reach a maximum at remote locations. Here we show that distance-dependent movement taxis can skew abundance distributions toward disturbed areas. We develop an advection-diffusion model based on basic movement behavior commonly observed in animal populations and parameterize the model from observations on radio-collared caribou in a boreal ecosystem. The model predicts maximum abundance at 3.7 km from cutovers and roads. Consistently, aerial surveys conducted over 161,920 km2 showed that the relative probability of caribou occurrence displays nonmonotonic changes with the distance to anthropogenic features, with a peak occurring at 4.5 km away from these features. This aggregation near disturbed areas thus provides the predators of this top-down-controlled, threatened herbivore species with specific locations to concentrate their search. The edge-effect theory developed here thus predicts that human activities should alter animal distribution and food web properties differently than anticipated from the current paradigm. Consideration of such nonmonotonic response to habitat edges may become essential to successful wildlife conservation. [ABSTRACT FROM AUTHOR]

Species interactions within food webs are driven by multiple constraints, including those imposed by seasonal changes in the environment. Ecologically sound definitions of seasons may therefore be a prerequisite for clarifying predator prey interactions. Most studies define biological seasons based on fixed schedules or on temporal changes in a single movement measurement. We used a novel clustering approach based on homogeneous space-use patterns of GPS-collared animals to reveal 7 biological seasons for caribou Rangifer tarandus caribou, and 5 for both moose Alces alces and grey wolves Canis lupus interacting in a boreal ecosystem. Subsequent evaluation of niche overlap showed that, as predicted, wolves had a stronger spatio-temporal connection with moose, its main prey, than with caribou. Movement constraints and limiting resource distributions similarly affected all species in some instances, but also caused temporal changes in the extent of niche overlap between wolves and its two prey. The risk that caribou faced was not only linked to the niche overlap with wolves, but also to the extent of wolf-moose niche overlap during the same period. Food-web properties emerged from the analysis, with temporal changes in relative niche overlap reflecting the strength of trophic interactions during the year. Our study demonstrates how the study of trophic interactions can benefit from comprehensive definitions of biological seasons. [ABSTRACT FROM AUTHOR]

The impact of anthropogenic disturbance on the fitness of prey should depend on the relative effect of human activities on different trophic levels. This verification remains rare, however, especially for large animals. We investigated the functional link between habitat selection of female caribou (Rangifer tarandus) and the survival of their calves, a fitness correlate. This top-down controlled population of the threatened forest-dwelling caribou inhabits a managed forest occupied by wolves (Canis lupus) and black bears (Ursus americanus). Sixty-one per cent of calves died from bear predation within two months following their birth. Variation in habitat selection tactics among mothers resulted in different mortality risks for their calves. When calves occupied areas with few deciduous trees, they were more likely to die from predation if the local road density was high. Although caribou are typically associated with pristine forests, females selected recent cutovers without negative impact on calf survival. This selection became detrimental, however, as regeneration took place in harvested stands owing to increased bear predation. We demonstrate that human disturbance has asymmetrical consequences on the trophic levels of a food web involving multiple large mammals, which resulted in habitat selection tactics with a greater short-term fitness payoff and, therefore, with higher evolutionary opportunity. [ABSTRACT FROM AUTHOR]

Logging negatively affects the threatened forest-dwelling caribou ( Rangifer tarandus caribou) through its positive effects on large predator populations. As recruitment is a key component of caribou population growth rate, we assessed calving rates of females and calf survival rates during the most critical period for calf survival, the calving period. We also identified causes of calf mortality and investigated the influence of predation risk, food availability, and human disturbance on habitat selection of females during the calving period at both the home-range and forest stand scales. We hypothesized that caribou should display habitat selection patterns to reduce predation risk at both scales. Using telemetry, we followed 22 females and their calves from 2004 to 2007 in a highly managed study area in Québec, Canada. Most females (78.5 ± 0.05 [SE]) gave birth each year, but only 46.3 ± 8.0% of the calves survived during the first 50 days following birth, and 57.3 ± 14.9% of them died from black bear ( Ursus americanus) predation. At the home-range scale, caribou selected calving areas located at upper slope positions and avoided high road density areas. Surprisingly, they also selected the forested habitat type having the lowest lateral cover (mixed and deciduous stands) while avoiding the highest cover (regenerating conifer stands). At the forest stand scale, caribou selected areas located at relatively high elevations and with a lower basal area of black spruce trees. The selection of upper slope positions likely favored spatial segregation between calving females and wolves ( Canis lupus) but not black bear. Our results suggest that calving females used areas from which they could visually detect approaching predators. While wolf avoidance appeared to be effective in a highly managed landscape, caribou did not appear to have adjusted their predator avoidance strategy to the recent increase in black bear abundance, who have benefited from increased food abundance. This situation requires focused attention from wildlife managers as logging activities are progressing towards the north within the core of forest-dwelling caribou range. © 2011 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Omnivores feed on animals with dynamic distributions and on plants with static distributions. The search tactics they adopt will not only define the risk for the targeted prey, but also for other prey that may be consumed when encountered. The potential impact of omnivores on the dynamics of multi-prey systems thus depends on resource selection and on the tactics used to find their prey. We present an approach that can clarify the foraging decisions of omnivores by combining analyses of habitat selection, local residency time, and interpatch movements. We use this framework to evaluate whether predation by omnivorous black bears on ungulate neonates resulted from an active search or from incidental encounters. We monitored 12 bears, 22 forest-dwelling caribou, and 36 moose during calving seasons. We estimated the spatial patterns in relative occurrence probability of ungulate neonates using Resource Selection Functions (RSFs). We also mapped plant abundance from vegetation surveys. RSF were then built to assess the link between bear distribution and the distribution of these three food types (vegetation, moose calves, caribou fawns). We further evaluated the search tactic used by bears that led to this spatial dependency by exploring patterns of residency times and interpatch movements. Bears did not select areas with a high probability of encounter with neonates, but selected areas with abundant vegetation. Surprisingly, bears displayed shorter residency times in vegetation-rich areas. The selection for vegetation-rich areas was therefore achieved by moving preferentially, but frequently, between areas offering abundant vegetation. Such frequent interpatch movements could result in high rates of fortuitous encounters with neonates, even if bears are not actively searching for them. To mitigate the impacts of forest harvesting on threatened caribou populations, vegetation-rich areas selected by bears (e.g. roadsides) should be segregated from large patches of mature conifer forest suitable for caribou. [ABSTRACT FROM AUTHOR]

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]

Stable isotope composition (δ13C and δ15N) of moose (Alces alces) and caribou (Rangifer tarandus) hair from the boreal forest of Jacques-Cartier Park and Cote-Nord (Quebec) and arctic tundra of Queen Maud Gulf and Southampton Island (Nunavut) was investigated as an indicator of dietary preferences and habitat use. Values of δ13Chair and δ15Nhair in moose were consistently lower compared to those of caribou. This is consistent with the depletion in 13C and 15N in the plants preferred by moose, essentially browse (shrub and tree leaves), compared to caribou forage, which included significant amounts of graminoids, lichen and fungi. The δ13Chair values of caribou differed between closed boreal forest and open-tundra ecosystems. This pattern followed that expected from the canopy effect observed in plant communities. Variation in δ15Nhair values of caribou was probably linked to the effect of different climatic conditions on plant communities. This study underlines the potential of isotopic analysis for studies on diet and habitat selection within a pure C3 plant environment. [ABSTRACT FROM AUTHOR]

Roads often negatively affect terrestrial wildlife, via habitat loss or fragmentation, noise, and direct mortality. We studied moose (Alces alces) behavior relative to a road network, in an area with a history of moose-vehicle accidents, to determine when moose were crossing roadways or using areas near roads and to investigate if environmental factors were involved in this behavior. We tracked 47 adult moose with Global Positioning System collars in a study area crossed by highways and forest roads. We hypothesized that moose would avoid crossing roads but would make occasional visits to roadsides to feed on sodium-rich vegetation and avoid biting insects. Further, we expected moose avoidance to be greater for highways than forest roads. We recorded 196,710 movement segments but only observed 328 highway and 1,172 forest-road crossings (16 and 10 times lower than expected by chance). Moose usually avoided road proximity up to ≥500 m on each side but 20% of collared moose made visits to areas within 50 m of highways, which might have resulted from moose searching for sodium in vegetation and roadside salt pools. In fact, vegetation along highways had higher sodium concentrations and was browsed in similar proportions to vegetation in adjacent forest, despite moose avoidance of these zones. Moose, however, did not use areas near roads more during periods of biting insect abundance. Our results supported the hypothesis of scale-dependent selection by moose; avoidance of highways at a coarse scale may confer long-term benefits, whereas selection of highway corridors at finer scales may be part of a strategy to overcome short-term limiting factors such as sodium deficiency. We found a positive relationship between home-range size and the proportion of road axes they contained, suggesting that moose either compensated for habitat loss or made specific movements along highways to gather sodium. The presence of sodium along highways likely increases moose-vehicle accident risks. Removal of salt pools or use of a de-icing salt other than sodium chloride should render highway surroundings less attractive to moose. [ABSTRACT FROM AUTHOR]

Sodium has many fundamental physiological functions in animals but is rare in boreal ecosystems where moose (Alces alces) thrive. In Québec (Canada), sodium is readily available in aquatic vegetation and in salt pools that form along highways. We do not know if moose are adopting specific behaviors to access sodium sources or if they simply use the sodium sources they encounter during their movements. We tested the hypothesis that moose modify both space and habitat use to gather sodium from salt pools. We expected moose to use salt pools mostly in spring and early summer, when needs are greatest and before aquatic vegetation has fully developed. We fitted 47 moose with Global Positioning System telemetry collars and collected data for 2 to 36 months between 2003 and 2006. We rarely located moose at salt pools (0.12% among the 95,007 locations collected). As we expected, use of salt pools was highest in late spring and in early summer, and we observed a time lag between peak use of salt pools compared to use of lakes and waterways, indicating moose fulfilled their sodium requirements in salt pools before aquatic vegetation was available. Moose selected salt pools over lakes and waterways when these 2 sodium sources were present in their home range and moved rapidly over large distances to reach them. Our results were consistent with moose using salt pools when they are likely to be sodium deficient. Salt pools were less accessible, required long-distance movements, and were located in habitually avoided areas along highways. Elimination of roadside salt pools should be considered among strategies to reduce cervid-vehicle collision risks in boreal environments. [ABSTRACT FROM AUTHOR]

We developed and validated a density-adjusted spatial model to predict moose (Alces alces) highway-crossing probability to see if the model could be used as an index of moose-vehicle collision risk. We installed Global Positioning System telemetry collars on 47 moose in the north of the Laurentides Wildlife Reserve, Québec, for 2-36 months. We recorded only 84 highway crossings in spring (0.29% of 28,967 2-hr steps) and 122 crossings in summer (0.18% of 68,337 2-hr steps), despite a high sampling effort and having captured moose close to highways. Moose movement rates during movement steps crossing a highway were on average 3 times higher than during the steps preceding or following highway crossing. Paths used by moose when crossing a highway were characterized by a high proportion of food stands, low proportion of lakes and rivers, and topography typical of a valley. Highway-crossing sites were located in valleys with brackish pools and forest stands providing coniferous cover but a low proportion of lakes and rivers. We adjusted moose crossing probability for local variation in moose density using aerial survey data and assessed crossing probability along the highways in the entire Laurentides Wildlife Reserve. We tested the model using moose-vehicle accident data from 1990 to 2002. The relationship between the density-adjusted crossing probability and number of accidents was relatively loose at the 1-km scale but improved markedly when using longer highway sections (5-15 km; r > 0.80). Our results demonstrate that roads and their surroundings are perceived as low-quality habitat by moose. We also conclude that road segments installed along secondary valleys could be a highly strategic site to deploy mitigation measures such as fences and that it could be desirable to increase the width of road shoulders to reduce forest cover and to eliminate brackish pools to reduce cervid-vehicle collisions. We suggest using empirical data such as location of vehicle-wildlife collisions to plan mitigation measures at a fine scale. [ABSTRACT FROM AUTHOR]

Wildlife-vehicle collisions cause numerous human fatalities and injuries, and generate considerable expenses in property damage each year. Certain characteristics of the road and its surroundings are known to have an impact on collision probability. Roadside salt pools increase the risk of collision by attracting moose (Alces alces) to the side of the road. In the Laurentides Wildlife Reserve of Québec, Canada, roadside salt pools were drained and filled with rocks to deter moose from drinking. We surveyed 12 roadside salt pools during 3 consecutive summers (2003-2005) from mid-May to mid-August. Seven salt pools were managed in autumn 2004, and 5 pools were left untreated. We equipped all 12 sites with electronic apparatus that allowed us to detect moose attendance and study their behavior. We also measured physical, chemical, and environmental characteristics of these pools and other unvisited pools in order to correlate moose attendance with specific habitat criteria. We found that moose mostly attended roadside salt pools from mid-June to mid-July, with a decrease in August. Moose attendance was significantly correlated with visual obstruction toward the road and water availability. Management of the pools caused a decrease in mean length of time moose spent at them. Number of visits decreased significantly at night (by 90%), which was when most visits occurred, but not during the day. The proposed management practice prevented all visiting moose from drinking brackish water. These results suggest that moose should eventually lose interest in treated salt pools, therefore decreasing the risk of moose-vehicle collisions on the road. [ABSTRACT FROM AUTHOR]

We tested the effectiveness of electric fences to reduce moose (Alces alces)-vehicle collisions in 2 fenced sectors (5 km and 10 km) using weekly track surveys and Global Positioning System telemetry. Number of moose tracks along highways decreased by approximately 80% following fence installation. Only 30% (16/53) of moose tracks observed on the road side of the fence were left by moose that crossed an operational fence; moose mostly entered the fenced corridor through openings (e.g., secondary roads) or at fence extremities. Electric fences also prevented 78% (7/9) of collared moose from crossing the highway in fenced sectors. Fences were less effective during occasional power failures. We suggest that circuit breakers should be used to prevent power failures and that there should be no opening along the fence line unless antiungulate structures are used. [ABSTRACT FROM AUTHOR]

The study of habitat selection usually compares assessments of habitat use to habitat availability. To investigate habitat selection of large mammals today, researchers must choose between a few very expensive Global Positioning System (GPS) telemetry collars that can provide many locations and several inexpensive very high frequency telemetry collars that will provide few numbers of locations (unless substantial resources are spent in the field). We investigated the effects of number of locations and sampled animals on the outcome of habitat-selection analyses. We evaluated whether tracking frequency and sample size of individuals influenced our ability to detect habitat selection. We used data obtained from adult female moose fitted with GPS collars to generate data sets simulating various sampling frequencies and sample sizes of individuals. Tracking schedules conformed to those commonly used in ungulate telemetry studies (1 location every 14, 7, or 3 d and 1 or 3 locations per d) as did animal sample sizes (between 8 and 20 individuals). We determined habitat use and availability at the landscape and home-range scales during summer-autumn and winter. Precision of habitat use and availability estimates did not improve markedly with increasing tracking frequency. Only results obtained with the least-intensive tracking schedule (1 location every 14 d) differed from those obtained with the other schedules and only in 25% of the cases. Above this threshold in tracking frequency, number of sampled animals was clearly more important than number of locations in detection of habitat selection. Our results indicated that habitat-selection analyses were more sensitive to inter- than intra-individual variability. Depending on study objectives, it may be more profitable to prioritize number of sampled individuals rather than number of locations per individual. We suggest methods allowing researchers to assess inter-individual variability while studying habitat selection. [ABSTRACT FROM AUTHOR]