Cette étude a évalué le jeu spatial entre le caribou forestier et le loup gris en forêt boréale. Nous avons étudié les déplacements de 31 caribous et 16 loups de l'automne au printemps, lorsque le caribou s'alimente principalement de lichen. Nos analyses indiquent que, dans les zones utilisées fortement par le loup, ce prédateur sélectionnait généralement les secteurs riches en lichen, alors que le caribou orientait ses déplacements vers les coupes forestières. La théorie des jeux qualifie d'effet saute-mouton cette réaction simultanée des deux espèces. Cet effet disparaissait toutefois dans les zones moins utilisées par le loup, car le caribou sélectionnait alors les secteurs riches en lichen. Ainsi, le jeu entre le caribou et le loup se caractérisait par un effet saute-mouton spatialement structuré. L'évaluation de la disponibilité des ressources alimentaires pour les populations vulnérables du caribou devrait donc tenir compte de l'impact du loup sur l'accessibilité de la nourriture. 111

Pour comprendre les relations plantes-herbivores, il ne faut pas seulement étudier les réponses des plantes, mais comment ces réponses influenceront la disponibilité de la ressource pour les herbivores. Ce mémoire vise à étudier cette interaction, en prenant comme modèle le caribou migrateur (Rangifer tarandus) et le bouleau glanduleux (Betula glandulosa Michx), à l'aide d'une expérience de simulation du broutement et de fertilisation en azote. Nos résultats indiquent que le bouleau est capable de compenser, c'est-à-dire recroître, suite à un broutement modéré du caribou. Cette compensation est indépendante de la disponibilité en azote, ce qui soutient le modèle de la ressource limitante, dont nous adaptons les prédictions pour une pression de broutement variable. De plus, même s'il y a compensation, la disponibilité en ressource pour le caribou diminue. Cette étude augmente notre compréhension de la relation entre le caribou et le bouleau, alors que les populations de caribous du Nunavik et du Nunatsiavut sont en déclin.

À la suite d’une coupe forestière, les parterres en régénération peuvent subir un enfeuillement favorable à l’orignal. L’accroissement des populations de loups qui s’en suit affecte alors les populations du caribou forestier. Ce projet vise à évaluer si la contribution de la coupe forestière à cette compétition apparente varie selon un gradient latitudinal. Nous avons modélisé la sélection d’habitat d’orignaux, de loups et de caribous. Après la prise en compte de l’âge de la coupe, l’enfeuillement des parterres diminuait avec la latitude. La sélection des parterres de coupe par les orignaux et les loups augmentait en fonction de leur enfeuillement. Les caribous évitaient les coupes, particulièrement celles riches en feuillus. La cooccurrence de l’orignal et du loup dans les coupes augmente donc en fonction de l’enfeuillement. Ainsi, la contribution de la coupe forestière à la compétition apparente dans le système orignal-loup-caribou devrait diminuer vers le nord de la forêt boréale. / Moose benefit from deciduous vegetation that becomes increasingly available during the regeneration of logged forests. This numerical response of moose populations can lead to an increase in gray wolf abundance, which impacts forest-dwelling caribou populations. This study evaluates if the contribution of logging to such apparent competition could vary along the latitudinal axis. We modelled habitat selection behaviour of moose, wolves and caribous monitored by telemetry. After controlling for time since harvest, deciduous vegetation availability decreased with increasing latitude. Moose and wolves avoided cutovers with low deciduous vegetation availability, while they selected harvested stands with high deciduous vegetation availability. Caribou avoided cutovers, and their avoidance increased with the level of deciduous regeneration. The co-occurrence between moose and wolves in cutovers increased with deciduous vegetation availability. Therefore, the contribution of logging to the apparent competition in the moose-wolf-caribou system should be stronger in southern than in northern boreal forest.

The winter ecology of mountain caribou (Rangifer tarandus caribou) in the North Thompson watershed of British Columbia was investigated over winters 1978-79 and 1979-80. The main objective of the study was to evaluate caribou movements and habitat use in relation to indices of energy cost of locomotion in snow and to forage availability, especially arboreal lichens. These data were collected in habitats from valley bottom to alpine throughout winter. Largely because of their high arboreal lichen productivity, mature forests are regarded by wildlife managers as essential winter habitat of caribou, leading to conflicts with forest harvesting. Data were compared between mature forests and other habitat types, to evaluate their importance to caribou. An index of caribou locomotion cost in snow was caribou track depth in snow. A significant regression between caribou track depth and human sinking depth in snow permitted an estimate of caribou locomotion costs in all habitats. Locomotion costs often were greater in cutovers than in mature forests, and broadly increased with elevation; while temporal trends were cyclical, due to alternating accumulations of fresh, soft snow followed by settlement and maturation of the surface snow. Analysis of fecal and rumen samples, and feeding-site inspections were used to determine caribou winter food habits. Arboreal lichens (Alectoria sp. and Bryoria spp.) dominated the diet by mid winter because terrestrial forage availability declined due to deep and crusted snowpacks. For each habitat, the absolute abundance of arboreal lichen was inventoried, and then this data together with snowpack measurements were used to estimate the relative availability of arboreal lichen over winter. Arboreal lichen availability was greatest in mature forests, and generally increased with elevation; it also increased within habitats as snow deepened and elevated caribou to higher forest canopy levels where greater quantities of lichen occurred. For the first time, radio telemetry was used to determine mountain caribou movements and habitat use. Observations of non-radiocollared caribou were also used in some analyses. In both used and unused habitats, estimated energy costs of locomotion and the availability of arboreal lichen were treated as indices of energy expenditure and of energy intake of foraging. These indices were qualitatively integrated in a net energy balance relationship to evaluate caribou movements and habitat use. Caribou appeared to follow a general optimizing strategy, balancing their energy expenditure for locomotion in snow against the energy available from forage, when both terrestrial and arboreal forages are considered. Throughout winter, caribou preferably used mature forests, which offered much greater energetic benefits than cutovers and immature forests. As snow in subalpine (Engelmann Spruce - Subalpine Fir Zone) and alpine summer habitats deepened over early winter, caribou migrated to lower subalpine and lower slope and valley (Interior Cedar - Hemlock Zone), mature forest habitats. Caribou locomotion conditions and forage availability, primarily of terrestrial forages, were most favourable at these lower elevations, despite lower arboreal lichen availability, because of snowfall interception by the forest canopy and lower snowfall. Firmer, mid-winter snowpack conditions allowed caribou to reascend to late winter range in higher elevation subalpine forests, which, because of greater arboreal lichen availabilities combined with moderated locomotion conditions, became the most favourable habitats. Minor elevational shifts during this period occurred in response to fluctuations in locomotion conditions caused by cycles of snow accumulation and snow settlement. This study confirmed that mature forests are required habitat for caribou throughout winter, by providing critical arboreal lichen forage, and compared to cutovers, having lower locomotion costs and greater availability of terrestrial forage. Proposed forest reserves above 1680 m elevation in the upper subalpine are insufficient therefore to ensure essential caribou winter habitat. Mature forests from valley bottoms to the lower subalpine must also be reserved. / Land and Food Systems, Faculty of / Graduate

Bien que les infections à Besnoitia tarandi sont documentées chez l’espèce Rangifer sp. depuis 1922, les données récoltées sur l’écologie et la distribution de cette parasitose demeurent rares. Les objectifs de cette étude ont donc été (i) d’identifier le meilleur tissu à échantillonner pour détecter les infections à Besnoitia tarandi dans les populations de caribous, (ii) de calculer la sensibilité et la spécificité de l’examen visuel comparativement à l’examen microscopique et (iii) d’identifier les facteurs de risques intrinsèques et extrinsèques associés à cette parasitose afin (iv) de comparer la prévalence et la densité des kystes parasitaires entre certains troupeaux. Nos résultats suggèrent que l'examen microscopique du derme superficiel d’une section de peau provenant du tiers moyen antérieur du métatarse devrait être privilégié pour dépister les infections par B. tarandi et en évaluer l'intensité. L’examen microscopique est également un outil très sensible comparativement à l’examen visuel des kystes parasitaires. Besnoitia tarandi, qui semble être absent du Groenland, a été observé dans environ un tiers des caribous nord-américains. Une variation saisonnière de prévalence et d'intensité de B. tarandi a été détectée; le parasite étant plus abondant chez cet hôte intermédiaire durant la période de l'automne/hiver comparativement à celle du printemps/été. Cet effet saisonnier pourrait être associé à une augmentation de l'abondance du parasite suite à la saison des insectes (i.e. été), supportant ainsi le rôle présumé des arthropodes piqueurs comme vecteurs de la maladie. Cette différence saisonnière pourrait aussi être expliquée par la diminution de la charge parasitaire par le système immunitaire et/ou par un taux de survie inférieur des animaux les plus parasités durant la saison froide. Les niveaux d'infection étaient légèrement plus élevés chez les mâles que chez les femelles, ce qui suggère soit une diminution du taux de mortalité, soit une exposition accrue ou une plus grande susceptibilité au parasite des mâles en comparaison aux femelles. La densité d’infection supérieure dans le troupeau Rivière-aux-Feuilles (Nunavik) suggère des niveaux d'exposition au parasite plus élevés et/ou une diminution des niveaux de résistance de ces caribous à ce protozoaire. Les résultats de cette étude démontrent que B. tarandi peut réduire les chances de survie des caribous infectés. Il sera donc important de continuer à surveiller les infections à B. tarandi surtout en cette période de changements climatiques. / Although Besnoitia tarandi has been described in Rangifer sp. for over 80 years, understanding of its ecology and distribution is still relatively limited. The objectives of this study were (i) to determine the anatomical sampling site that enhances detection of Besnoitia tarandi infections in caribou populations; (ii) to evaluate the relative sensitivity and specificity of the in situ macroscopic assessment for diagnosis of besnoitiosis compared to the microscopic evaluation; and (iii) to identify potential risks factors associated with the prevalence and intensity of B. tarandi cysts and compare these across different populations. Our results suggest that calculating the number of cysts present in the superficial dermis of a skin section of the anterior mid-third of the metatarsus region by microscopic examination should be favored in order to monitor the presence and intensity of B. tarandi infections. Macroscopic assessment of B. tarandi cysts was not a sensitive method compared to that of a microscopic analysis. Besnoitia tarandi seems to be absent from Greenland but has been encountered in approximately one third of North-American caribou. A seasonal effect was noticed in the prevalence and intensity of B. tarandi infections; the parasite being more abundant in caribou sampled during the fall/winter period compared to the spring/summer period. This effect could reflect the increase abundance of B. tarandi following the end of the insect season (i.e. summer), supporting the role of arthropods as vectors of transmission. Reduction of the parasite burden by the immune system and/or a lower winter survival rate of severely infected caribou could explain the seasonal difference. The slightly higher prevalence in males suggests lower mortality rate, higher exposure and/or higher susceptibility to the parasite in infected males when compared to infected females. The apparent higher density of infection by B. tarandi in the Rivière-aux-Feuilles herd (Nunavik, Québec) suggests either higher exposure to the parasite or reduced resistance of caribou from this herd. The findings of this study suggest that infection by B. tarandi might reduce survival of individual animals; hence, the dynamic between this parasite and its hosts is worth further investigation, especially in these days of changing Arctic environment.

The primary objective of this thesis was to develop knowledge and understanding about how traditional resources can be used for entrepreneurship and economic development. This was accomplished by systematically studying how the Canadian Inuit, Swedish Sámi and other indigenous people use Rangifer tarandus for enterprise. The Inuit and Sámi are indigenous circumpolar people living in Canada and Northern Europe for more than 4000 years. Rangifer tarandus known as caribou or tuktu by the Canadian Inuit and reindeer by the Sámi has been a key resource for survival. A literature review was conducted relating 1) to Canadian Inuit, Swedish Sámi and other selected circumpolar indigenous people use of caribou or reindeer for enterprise, and 2) indigenous entrepreneurship, particularly from traditional resources, and how this is affected by context and culture. Research methods included descriptive exploratory comparative cases, participative observation, snowball sampling as well as indigenous research methods. Five field sites were visited: Rankin Inlet and Coral Harbour in Nunavut; Inukjuak in Nunavik, Quebec; Happy Valley-Goose Bay/ North West River in Labrador; and Jokkmokk, in Northern Sweden. The thesis explored: 1) Why are the Inuit hunters of caribou and the Sámi herders of reindeer? 2) What were the products and value-added processing? 3) Why have the Sámi successfully sold their meat and products in the international market while the Inuit have only recently begun to do so? 4) How has their culture and traditional knowledge affected the entrepreneurship including innovation and opportunity recognition? 5) What barriers have they faced and how have these been overcome? 6) How have they measured the success of their enterprises? 7) What can they learn from each other? The findings indicated the Inuit and Sámi uses of caribou and reindeer for enterprise were very different. Context and culture were extremely important. Indigenous people living at similar latitudes and making use of a similar species had very different trajectories and outcomes in indigenous economic development and entrepreneurship from Rangifer tarandus. Themes such as resource availability, cultural propensity, remoteness and geographic location, kinship and social capital, infrastructure, measures of success, indigenous knowledge and wisdom, and innovation and adaptation were important. This work made a significant contribution as little consideration had been given to the voice and perspectives of the Canadian Inuit and Swedish Sámi in the emerging field of indigenous entrepreneurship especially as it relates to traditional resources and practices. It also helped to identify other potential commercial uses of caribou thus it provided more potential value added from the commercial harvesting and processing. These opportunities could assist in increasing Inuit employment, income, self-reliance, and community esteem. The research findings have implications for 1) the field of indigenous entrepreneurship, 2) policy makers, and 3) indigenous entrepreneurship education. It provides international comparisons of two indigenous peoples using a similar species and focused on the use of traditional resources and culture as a basis for business creation and operation.

Forty-four wolves in 3 boreal forest sites in Ontario were monitored via GPS radiotelemetry during 2010 and 2011 to examine spatial responses to variation in prey density. Home ranges were defined using a Brownian bridge utilization distribution, and a resource utilization function was calculated for each pack in winter and summer, based on habitat, topography, and prey density. Wolf territories were smaller where moose density was higher. Third order selection (within home range) varied by pack and season. Wolves generally selected for sloping areas, areas near water, and stands with deciduous or regenerating forest, but selected against areas with dense conifer cover. Roads were most important in summer, especially in those territories with large road networks. Habitat use in a mild winter was similar to habitat use in summer. Variable resource selection among packs emphasizes the adaptable, generalist nature of wolves even in the relatively homogenous the boreal shield. / National Science and Engineering Research Council, Ontario Graduate Scholarships, Ontario Ministry of Natural Resources - Wildlife Research and Development Section, Center for Northern Forest Ecosystem Research, Ontario Ministry of Natural Resources, Canadian Forest Service, Forest Ecosystem Science Cooperative

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