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Summary 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 km 2 of boreal forest in Québec, Canada. Autologistic models were estimated by comparing the characteristics of landscapes (201 km 2 ) centred on each centroid to an equal number of randomly located landscapes, with an autocovariate controlling for the nonindependence 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.

Dynamics of herbivore populations can be influenced both by density-dependent processes and climate. We used age-atharvest data for adult female white-tailed deer (Odocoileus virginianus) collected over 23 years to estimate survival and reproduction by age class and to identify effects of environmental factors. The study population was located on Anticosti Island (QC, Canada), at the northern limit of the species' range; the population was at high density, and the landscape had scarce forage and abundant snow during winter. Despite severe environmental conditions, population growth apparently increased during the study; adult survival was similar to other populations, although reproduction appeared lower. Winter severity was not related to survival, but density affected adult female survival. Density at estrus was the main factor influencing reproduction of 2-and 3-4-year-olds and also affected reproduction of prime-aged females (5-9-yr-olds), but not of older females. Reproductive rate of younger females was influenced by environmental conditions in autumn, such as high density or snow conditions that limited forage availability. Reproductive success of 5-9-and L 10-year-old females appeared dependent on spring conditions favoring high-quality forage, probably through effects on neonatal survival. Relative to other studies on northern ungulates, demographic processes in our study appeared to be more affected by autumn and spring climate, in addition to population density, than by winter climate. We thus propose that population density, as well as autumn and spring climate, should be considered in management strategies. Harvest data offered a unique opportunity to study forest ungulates, for which individual monitoring is rarely possible.

We examined published historical information, reports on aerial surveys conducted since 1953, and harvest data collected since 1971 to describe changes in the distribution and abundance of Caribou (Rangifer tarandus) in Québec. The southern limit of the Caribou distribution diminished considerably in the late 19 th century, and the decline in numbers probably continued until the 1960s and 1970s east of the 62 nd meridian. South of the 49 th parallel, only four small populations still persist. Despite the fact that all Caribou of the province were assigned to the same sub-species (R. t. caribou), three ecotypes with specific habitats and behaviour are found. The Barren-Ground ecotype, the only migratory form, is found north of the 52 nd parallel. This ecotype currently occupies ≈ 255 000 km 2 in fall and winter, mainly in the ecological subzones of the forest tundra and the taiga. The Barren-Ground Caribou was characterized by a very low abundance from the end of the 19 th century until the mid1950s, but increased markedly thereafter reaching over a million individuals at the beginning of the 1990s. Populations of the Mountain ecotype have been identified in the southeastern and, possibly, in the northeastern parts of the province. The latter Mountain population is virtually unknown. The southeastern population is sedentary and uses mainly the boreal forest. This population has decreased over the last century and currently numbers only ≈ 140 individuals. Finally, the Forest-Dwelling ecotype is found discontinuously, mainly between the 49 th and 55 th parallels. Its current distribution covers ≈ 235 000 km 2 , mainly east of the 72 nd meridian. This sedentary ecotype is found almost exclusively in the boreal forest, principally in areas with long forest fire cycles. Its abundance has also decreased over the years. Large Forest-Dwelling populations still persisted during the 1950s and 1960s, but they apparently disappeared. The current abundance is not known precisely, but based on density estimates and considering the current distribution, it probably does not exceed 3000 individuals. Current data are insufficient to identify precisely the causes of the population decline, although hunting seems to be an important proximal cause. L'abondance actuelle n'est pas connue mais elle pourrait difficilement dépasser 3000 individus si l'on se base sur les estimations de la densité et de l'aire de répartition. Les données disponibles sont insuffisantes pour identifier les causes exactes des diminutions d'effectifs bien que la chasse semble une cause proximale importante.

The forest-dwelling ecotype of woodland caribou (Rangifer tarandus caribou) is vulnerable to predation, hunting, and disturbances due to anthropogenic activities. Its strategies of space and habitat use are oriented towards reducing the effects of these limiting factors. Caribou occupy large home ranges, undertake extensive movements, and avoid fragmented areas. They use various habitats, but especially mature and over-mature conifer stands with irregular structure, which are less suitable for other ungulates, wolves and black bears. In order to protect habitat for forest-dwelling caribou, we suggest an ecosystem approach based on the protection of large forested blocks, the concentration of forest harvesting in large management blocks, and the maintenance of habitat connectivity. This strategy focuses on short-term conservation of minimum caribou habitats in the protected blocks, a medium-term habitat recovery in the management blocks, the maintenance of forest activities, and facilitation of seasonal and dispersal movements. Within the management blocks, we recommend creation of an irregular forest structure similar to the pattern created by natural disturbances inherent to spruce-moss forests. These guidelines have been tested in Québec for the last few years and were well received by forest and wildlife agencies as well as the forest industry.Key words: adaptive management, boreal forest, ecosystem management, forest-dwelling ecotype, forest management, spruce forest, woodland caribou L'écotype forestier du caribou des bois (Rangifer tarandus caribou) est vulnérable à la prédation, à la chasse et aux dérangements anthropiques. Ses stratégies d'utilisation de l'espace et des habitats visent à réduire l'impact de ces facteurs. Il occupe de grands domaines vitaux, effectue de grands déplacements et évite les milieux fragmentés par la coupe et les perturbations naturelles. Il utilise différents habitats mais surtout les forêts résineuses matures et surannées de structure irrégulière moins propices aux autres cervidés et aux pré-dateurs. Pour aménager l'habitat du caribou forestier, nous recommandons une approche écosystémique basée sur la protection de grands massifs forestiers, la concentration des coupes forestières dans de grands blocs d'aménagement et le maintien de la connectivité des habitats. Cette stratégie permettra de conserver un habitat minimum à court terme, de reconstituer des habitats propices à moyen terme, de maintenir les activités forestières et de faciliter les mouvements saisonniers et la dispersion du caribou. À l'intérieur des blocs d'aménagement, nous proposons de s'inspirer du régime des perturbations naturelles ayant cours dans la pessière à mousses pour régénérer des forêts de structure irrégulière. Ces lignes directrices sont expérimentées au Québec depuis quelques années et elles furent bien reçues par les agences forestières et fauniques aussi bien que par l'industrie forestière.Mots-clés : aménagement forestier, aménagement écosystémique, caribou des bois, écotype forestier, forêt ...