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AbstractWe assessed habitat selection of moose in a study area containing 2 highways and a network of forest roads in Quebec, Canada. We tested the hypothesis that roadways would affect moose habitat selection and that moose behaviour would vary with time, proximity to roads, type of roadway, and environmental characteristics (i.e., habitat and topography). We equipped 47 moose with GPS telemetry collars and assessed habitat selection using resource selection functions. Moose searched primarily for areas with high forage availability, but they also avoided highways and forest roads, although avoidance usually disappeared beyond 100–250 m. Avoidance was not directly proportional to noise disturbance; moose systematically avoided the first 100 m adjacent to forest roads, while habitats adjacent to highway sides were sometimes used in proportion to their availability. The benefits of using habitats adjacent to highways may be greater than the costs to moose, which was not always the case for forest roads. The road-avoidance zone varied seasonally but was generally wider for males than females, suggesting that males were more sensitive to road disturbance. We believe that moose frequent highways and associated roadsides to find food and mineral salts, and possibly to reduce predation risk for females. Topography was also an important correlate of habitat selection by moose, especially for females, which had significant selection coefficients for altitude and slope in almost every season. Proper assessment of human impacts on ungulates in natural environments requires consideration of unpaved forest roads. In a study area with a small human footprint and low road density (0.16 km·km−2), moose selection patterns suggested they minimized potential risks associated with highways at the coarse scale while seeking short-term benefits of highway roadsides, i.e., sodium in vegetation and pools, at the finer spatial scale.

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 Anthropogenic disturbances can promote establishment and growth of predator populations in areas where secondary prey can then become threatened. In this study, we investigated habitat selection of eastern coyotes (Canis latrans), a relatively new predator in the vicinity of an endangered population of caribou (Rangifer tarandus caribou). We hypothesized that coyotes in the boreal forest depend mainly on disturbed habitat, particularly that of anthropogenic origin, because these habitats provide increased food accessibility. Coyotes would likely take advantage of moose (Alces alces) carcasses, berries, and snowshoe hares (Lepus americanus) found in open habitats created by logging. To test these predictions, we described coyote diet and habitat selection at different spatial and temporal levels and then compared resource availability between habitats. To do so, we installed Global Positioning System radiocollars on 23 individual coyotes in the Gaspésie Peninsula, eastern Québec, Canada. Coyotes selected clear-cuts of 5–20 years and avoided mature coniferous forests both at the landscape and home-range levels. Clear-cuts of 5–20 years were found to contain a high availability of moose carcasses and berries, and vulnerability of snowshoe hares is known to increase in clear-cuts. The importance of these 3 food resources was confirmed by the characteristics of core areas used by coyotes and diet analysis. Moose remains were found at 45% of core areas and coyote diet comprised 51% moose on an annual basis. Anthropogenic disturbances in the boreal forest thus seem to benefit coyotes. Our results indicated that the relationship between coyotes and caribou likely involves spillover predation. This knowledge allows managers to consider spillover predation by coyotes as a possible threat for endangered caribou population when the predator depends mainly on habitat of anthropogenic origin and to suggest methods to alleviate it when developing management plans.

AbstractLong snowy winters combined with a short growing season make boreal forests an unproductive environment that challenges black bears (Ursus americanus).We used resource selection functions (based on GPS telemetry of 16 bears), diet analysis, surveys of plant phenology, and vegetation inventories to study adaptations of black bears to boreal forest. Because plants are heavily favoured in bear diets, we expected diet composition to reflect their temporal availability. We anticipated that bears would make choices among land cover types and specific topographic conditions in order to select plants that would fulfil their energetic demands throughout the active period. We also predicted that bears would select habitats modified by insect outbreaks or forest harvesting because these disturbances likely increase resource availability. We found supporting evidence for all of our predictions. (1) Bear diet was closely linked to plant availability. (2) Bears made seasonal altitudinal movements and selected sites according to solar irradiation, tracking the availability of the most digestible plants. Accordingly, bears relied on high-altitude graminoids in spring, a variety of fleshy fruits in summer, and mainly Sorbus americanaberries in autumn. (3) Land covers resulting from clearcutting and insect outbreaks increased resource availability for bears and were preferred from summer to autumn. In our study area, black bears are considered predators of a threatened caribou (Rangifer tarandus) population. Even so, we did not find any caribou remains in bear scats. However, our results show that forestry practices, such as clearcutting near the caribou range, could contribute to increased bear presence and thus increase the probability of predation.

AbstractRoads 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: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 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 km2and 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.

AbstractWoodland caribou (Rangifer tarandus caribou), a threatened species in Canada, inhabit landscapes dominated by mature and over-mature coniferous stands and tend to avoid areas used by other cervids, wolves (Canis lupus), and humans. We hypothesized that habitat modifications through logging and forest fire alter the space-use pattern of woodland caribou and result ultimately in lowered density. To test this hypothesis, density, distribution, space-use patterns, and mortality of caribou in disturbed landscapes (DLs) and undisturbed landscapes (ULs) of central Québec were quantified by a systematic aerial survey (42 539 km2) and telemetry of 68 adult caribou females. A ground survey of terrestrial and arboreal lichens was carried out to estimate production of lichens in DLs and ULs. Three populations that occupied between 10 000 and 15 000 km2were identified in the study area. Caribou abundance was not limited by intraspecific competition for food. Production of terrestrial lichens was estimated to support 3 to 4 times the surveyed caribou density (1.2–2.1–100 km−2). Pregnancy rate was almost 100%, indicating that females were not food-limited. Space-use patterns were affected by forest disturbance. In DLs, caribou increased home range sizes and reduced fidelity to seasonal and annual home ranges, probably to avoid disturbed habitats. In response, the probability of surviving decreased with the extent of DL within home ranges. To help keep direct and indirect sources of caribou mortality at very low levels, forest management strategies should be oriented toward the protection of large interconnected blocks of forest to favour caribou spacing away from humans and predators and to maintain adequate space-use strategies.

ABSTRACT 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 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:We tested the effectiveness of electric fences to reduce moose (Alcesalces)-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 anti-ungulate structures are used.

AbstractThe 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.

Deer-vehicle accidents are an increasing problem in many regions of the world. To elaborate effective mitigation measures, it is necessary to determine environmental factors associated with the occurrence of such accidents. The Lauren-tides Wildlife Reserve in Quebec, Canada, is a prime example of an area having a long-lasting problem of moose-vehicle accidents (MVAs). We tested the effect of the spatial and temporal variables most likely to influence MVAs in this area based on accidents recorded over a 13-year period. Data collected included the date and time of each collision as well as the position of the accident relative to the closest 1-km road marker. We calculated 10 variables to assess moose habitat suitability, moose density, topography and road design for every 1-km road segment. There was a total of 754 MVAs during 1990–2002. The period with the highest number of accidents was the second half of June but accident frequency remained relatively high from mid-May to late August. The risk of accident per vehicle was at least 2–3 times higher at night (when traffic volume was lowest) than during any other time of the day. Also, MVAs were over 42% more frequent on Fridays, when road traffic levels were highest. The probability of an MVA increased when air temperature and atmospheric pressure were high. The MVA rate increased with moose density, in the presence of at least one brackish pool (by 80%) and when a valley traversed the road (by 120%). Implications of our results in the choice of appropriate mitigation measures are discussed. Future work should aim to describe habitat characteristics at the actual collision site.

Abstract:Among ungulate species living in boreal regions, moose (Alces alces) are most likely to suffer from heat stress since they have a relatively low upper critical temperature (14 °C in summer and -5 °C in winter). We tested the hypothesis that moose adopt behaviours to reduce thermoregulatory costs. We predicted that moose exposed to high intensities of solar radiation or high air temperatures would 1) seek a type of vegetation association that provides thermal shelter and 2) reduce activity. We also predicted that these behaviours would be most evident in summer. Thermal-shelter use and activity of 30 free-ranging moose were measured over 3 y in a 940-km2study area of boreal forest using GPS telemetry collars. The effect of solar radiation and air temperature on thermal-shelter use and activity were assessed using logistic and multiple regression analyses. Habitat use and activity rates of moose were related to air temperature but not solar radiation. The probability of finding moose in thermal shelters increased with air temperature in summer and fall. Moose activity did not decrease as air temperature increased, but it increased at night during hot periods. As expected, moose response to thermal conditions was most noted in summer. Our results suggest that moose reduce exposure to thermal stress by using thermal shelters during the day and by increasing nocturnal activity. These behavioural adaptations allow moose to cope with thermal stress on a small temporal scale. Negative effects of heat stress could be important in areas where air temperatures are very high for extended periods of time or where thermal cover is scarce.