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Regional analyses assessing the vulnerabilities of forest ecosystems and the forest sector to climate change are key to considering the heterogeneity of climate change impacts as well as the fact that risks, opportunities, and adaptation capacities might differ regionally. Here we provide the Regional Integrated Assessment of climate change on Quebec's forests, a work that involved several research teams and focused on climate change impacts on Quebec's commercial forests and on potential adaptation solutions. Our work showed that climate change will alter several ecological processes within Quebec's forests. These changes will result in important modifications in forest landscapes. Harvest will cumulate with climate change effects to further alter future forest landscapes, which will also have consequences on wildlife habitats (including woodland caribou habitat), avian biodiversity, carbon budget, and a variety of forest landscape values for Indigenous peoples. The adaptation of the forest sector will be crucial to mitigate the impacts of climate change on forest ecosystem goods and services and improve their resilience. Moving forward, a broad range of adaptation measures, notably through reducing harvest levels, should be explored to help strike a balance among social, ecological, and economic values. We conclude that without climate adaptation, strong negative economic and ecological impacts will likely affect Quebec's forests. Key words: Quebec, boreal forest, synthesis, ecosystem services, regional analyses Les analyses regionales evaluant la vulnerabilite des ecosystemes forestiers et du secteur forestier aux changements climatiques sont essentielles pour prendre en compte l'heterogeneite des impacts des changements climatiques, mais aussi le fait que les risques, les opportunites et les capacites d'adaptation peuvent differer d'une region a l'autre. Nous presentons ici l'evaluation regionale integree des changements climatiques sur les forets du Quebec, un travail qui a implique plusieurs equipes de recherche et qui s'est concentre sur les impacts des changements climatiques sur les forets commerciales du Quebec et sur les solutions d'adaptation a ces changements. Nos travaux montrent que les changements climatiques pourraient modifier plusieurs processus ecologiques dans les forets du Quebec. Ces changements entraineront d'importantes modifications des paysages forestiers. La recolte forestiere pourrait s'additionner aux changements climatiques pour modifier davantage les futurs paysages forestiers, ce qui pourrait egalement avoir des consequences sur les habitats fauniques (notamment ceux du caribou forestier), la biodiversite aviaire, le bilan carbone et les valeurs des paysages forestiers pour les Peuples autochtones. Nous preconisons que l'adaptation du secteur forestier sera essentielle afin d'attenuer les impacts des changements climatiques sur plusieurs biens et services ecosystemiques forestiers. Ces strategies devraient ameliorer la resilience des services ecosystemiques. Par exemple, la reduction de la recolte pourrait permettre de maintenir l'habitat du caribou, favoriser la biodiversite aviaire, bonifier la capacite de stockage du carbone et profiter aux activites traditionnelles autochtones. La reduction des taux de recolte du bois pourrait aussi aider a reduire les echecs de regeneration apres les feux dans les regions oU ceux-ci sont actuellement communs, ou dans celles qui seront a risque dans le futur. Sur la base de nos travaux, nous concluons qu'omettre de mettre en oeuvre des options d'adaptation aux changements climatiques pourrait representer des impacts economiques et ecologiques negatifs importants pour les forets du Quebec. Mots-cles : Quebec, foret boreale, synthese, services ecosystemiques, analyses regionales, 1. Introduction The science is clear: human-caused climate change has been warming the planet by 1.1[degrees]C since 1880, with a recent rate of increase of 0.18[degrees]C per decade since 1981 [...]

Sexual size dimorphism is a common phenomenon in mammals, and researchers have been trying to demonstrate the evolutionary causes leading to sexual dimorphism. Two main hypotheses emerged: (1) the sexual selection hypothesis and (2) the sexual competition hypothesis (also called resource partitioning hypothesis). Here, we attempted to link sexual dimorphism in fishers (Pekania pennanti (Erxleben, 1777)) with their fall diet using stable isotope profiling and body and skull measurements. We used the carcasses of 39 fishers which were caught in eastern Quebec during fall 2014 by volunteer trappers as well as several potential prey items ranging from small rodents to cervids. We expected minimal niche overlap between sexes, as males should be able to exploit different prey species than females. We also expected to observe an effect of age class (adults vs. juveniles) on trophic niche. As expected, we found great evidence of sexual dimorphism in both body mass and skull measurements: males were heavier and longer than females and had a larger zygomatic and intracanine width and a longer skull. While proportions of prey in diet according to sex and age did not vary greatly, we found some evidence of niche partitioning using Layman's metrics. Indeed, females tended to have a less diversified and more similar diet compared to one another, whereas males showed more diversified and contrasted diets. Despite our limited sample size, our findings provide partial support to the sexual competition hypothesis, as the difference in body and skull size based on sex could have evolved to lessen intraspecific competition in fishers. Key words: intraspecific competition, fisher, niche partitioning, Pekania pennanti, sexual size dimorphism, stable isotopes Le dimorphisme sexuel de la taille est un phenomene repandu chez les mammiferes, et des chercheurs tentent d'en demontrer les causes evolutives. Deux hypotheses principales en ressortent, a savoir : (1) l'hypothese de la selection sexuelle et (2) l'hypothese de la competition sexuelle (aussi appelee hypothese du partitionnement des ressources). Dans cet article, nous tentons de relier le dimorphisme sexuel chez le pekan (Pekania pennanti (Erxleben, 1777)) a son regime alimentaire automnal a l'aide du profilage d'isotopes stables et de parametres morphometriques du corps et du crane. Nous avons utilise 39 carcasses de pekan captures par des piegeurs volontaires dans l'est du Quebec durant l'automne 2014 et une gamme de proies potentielles allant de petits rongeurs a des cervides. Nous nous attendions a un chevauchement minimal des niches entre les sexes, etant donne que les males devraient pouvoir exploiter differentes especes de proies que les femelles. Nous nous attendions egalement a observer un efet de la classe d'age (adultes ou juveniles) sur la niche trophique. Comme prevu, nous relevons d'importants indices d'un dimorphisme sexuel tant de la masse corporelle que des parametres craniens; les males sont plus lourds et plus longs que les femelles et presentent des largeurs zygomatique et intracanine plus grandes et un crane plus long. Si les proportions de differentes proies dans le regime alimentaire ne varient pas beaucoup, les parametres de Layman font ressortir des indices de partitionnement des niches. Le regime alimentaire des femelles a en efet tendance a etre moins diversifiee et plus homogene entre individus que celui des males. Malgre la taille limitee de l'echantillon etudie, ces resultats appuient partiellement l'hypothese de la competition sexuelle, les differences de la taille du corps et du crane selon le sexe pouvant etre apparues pour reduire la competition intraspecifique chez le pekan. Mots-cles : competition intraspecifique, pekan, partitionnement de niche, Pekania pennanti, dimorphisme sexuel de la taille, isotopes stables, Introduction Competition may have a strong influence on the ecological characteristics of species as well as on their evolutionary trajectories (Svanback and Bolnick 2007; Svanback et al. 2009). Competition occurs [...]

Abstract: Simulated wolf howling sessions are a popular ecotourism activity, but no exhaustive evaluation has been made on their potential impacts on wolf ecology. We evaluated the effects of simulated [...]

Extensive forest management aims at minimizing differences between managed and natural forests and at contributing to the conservation of endangered species such as the Atlantic-Gaspesie caribou. The decline of this isolated population was exacerbated by intensive forest practices, as the over-representation of regenerating forests supports high densities of bears and coyotes. These predators select such stands for the high availability of berries and browse suitable to alternative prey, especially moose. Our objective was to verify whether extensive treatments can provide suitable habitat characteristics for caribou. We compared the impacts of different intensive and extensive treatments on habitat attributes known to be selected by caribou, moose, and their predators. We sampled 291 sites in seven treatments and in mature coniferous forests (as the control). A partial canonical correspondence analysis highlighted which treatments maintain habitat attributes that are comparable with those found in mature forests, including some characteristics suitable for caribou such as a substantial biomass of arboreal lichen and a lower availability of resources for predators. Although being more suitable than the three intensive treatments tested, none of the four extensive treatments we studied provided similar habitat conditions to mature forest. Favouring extensive treatments could nevertheless be a relevant conservation compromise at the forest stand level, but their utility remains uncertain under the maximum sustainable yield paradigm as they impact a larger area. Key words: black bear--coyote--caribou system, extensive vs. intensive management practices, habitat characteristics, mature forest attributes, silvicultural treatments. L'amenagement forestier extensif vise a reduire les ecarts entre les forets naturelles et amenagees et a contribuer a la conservation d'especes a statut precaire, comme le caribou de la Gaspesie-Atlantique. Le declin de cette population isolee a ete exacerbe par une exploitation forestiere intensive, puisque la surrepresentation des peuplements en regeneration permet de supporter d'importantes densites d'ours et de coyotes. Ces predateurs selectionnent ces peuplements pour l'abondance elevee de petits fruits et de brout favorables aux proies alternatives, particulierement l'orignal. Notre objectif etait de verifier si des traitements extensifs pouvaient offrir des caracteristiques d'habitat favorables au caribou. Nous avons compare les impacts de differents traitements intensifs et extensifs sur les attributs d'habitat connus pour etre selectionnes par le caribou, l'orignal et leurs predateurs. Nous avons echantillonne 291 sites dans 7 traitements et dans des forets resineuses matures (comme temoins). Une analyse canonique de correspondance partielle a permis d'identifier quels traitements maintenaient des attributs d'habitat comparables a ceux retrouves en foret mature, dont certains sont importants pour le caribou, comme une biomasse substantielle de lichen arboricole et une disponibilite moindre en ressources alimentaires pour les predateurs. Bien que plus favorables que les 3 traitements intensifs testes, aucun des 4 traitements extensifs etudies n'offrait de conditions d'habitats similaires aux forets matures. Favoriser les traitements extensifs pourrait neanmoins s'averer un compromis de conservation pertinent a l'echelle du peuplement forestier, mais leur utilite reste incertaine sous le paradigme du rendement maximum soutenu puisqu'ils impactent une plus grande superficie. Mots-cles: systeme ours noir--coyote--caribou, amenagement extensif vs intensif, caracteristiques d'habitat, attributs de foret mature, traitements silvicoles., Introduction Species have evolved within the constraints and opportunities induced by natural disturbance regimes (Seymour and Hunter 1999), and the emulation of these disturbances is now considered as the best [...]

Long-term exploitation of boreal ecosystems often results in a reduced range of ecological conditions that threatens several species. In most boreal jurisdictions, the northern extent of commercial forestry corresponds to economical rather than ecological considerations. Our general objective is to offer guidance for sustainable boreal forest management by using a biodiversity criterion based on three indicators. The first two indicators are part of a coarse filter referring to the proportion and fragmentation of tall, dense forest habitats, whereas a third one uses a fine filter for specific requirements of boreal caribou. We applied the methodology with and without anthropogenic disturbances on 1114 land districts to contrast the preindustrial potential and current capacity of Quebec's boreal forest to support forest management. Originally, 826 districts (74%) were above the 20% cutoff value for the minimum proportion of tall, dense forest habitats. Among the 567 districts currently under forest management, 45 did not reach this value because of past anthropogenic disturbances. Originally, 88% of the districts had sufficient undisturbed habitats to maintain caribou populations, but anthropogenic disturbances reduced this proportion to 51%. The proposed methodology could contribute to delineating areas where sustainable forest management can be implemented. Our results also clearly show that management targets of the last decades were insufficient to prevent loss of habitats below strict minimum ecological thresholds. Our approach offers a general framework that could be adapted to other forested regions to attain similar biodiversity conservation objectives. Key words: biodiversity indicators, boreal forest, cumulative effects, caribou, habitat loss. L'exploitation a long terme des ecosystemes boreaux se traduit souvent par une gamme reduite de conditions ecologiques qui menace plusieurs especes. Dans la plupart des pays, l'extension nordique de la foresterie commerciale s'appuie plutot sur des considerations economiques qu'ecologiques. Notre objectif general est de donner des orientations pour la gestion durable de la foret boreale en utilisant un critere de biodiversite, sur la base de trois indicateurs. Les deux premiers indicateurs font partie d'un filtre brut se referant a la proportion et a la fragmentation d'habitats denses et hauts tandis qu'un troisieme utilise une approche de filtre fin pour repondre aux besoins specifiques du caribou forestier. Nous avons applique la methode avec et sans perturbations anthropiques sur 1114 districts ecologiques afin de comparer la capacite actuelle et le potentiel initial de la foret boreale du Quebec pour soutenir la gestion durable de la foret. A l'origine, 826 districts (74 %) etaient au-dessus d'une proportion de 20 % d'habitats forestiers denses et hauts. Parmi les 567 districts actuellement soumis a l'amenagement forestier, 45 d'entre eux n'atteignaient pas cette valeur seuil en raison de perturbations anthropiques passees. A l'origine, 88 % des districts avaient suffisamment d'habitats non perturbes pour maintenir des populations de caribous, mais les perturbations anthropiques ont reduit cette proportion a 51 %. La methodologie proposee pourrait contribuer a delimiter les zones ou la gestion durable des forets peut etre mise en reuvre. Nos resultats mettent aussi en evidence que les mesures de conservation mises en place dans les territoires amenages au cours des dernieres decennies n'ont pas suffi a empecher la perte d'habitats en deca de seuils ecologiques minimums. Notre approche offre un cadre general qui pourrait etre adaptable a d'autres regions forestieres afin d'atteindre les memes objectifs de maintien de la biodiversite. Mots-cles: indicateurs de biodiversite, foret boreale, effets cumulatifs, caribou, perte d'habitat., Introduction Around the world, nearly 50% of the primary forests that remain are located in the sparsely populated boreal zone (Mackey et al. 2014). Such forests, where ecological processes have [...]

The main environmental factors that drive lichen communities are still poorly known in northern boreal ecosystems. This study compares the effects of forest stand characteristics (height, canopy cover, and age) on fruticose epiphytic and terricolous lichen communities across a large region located at the interface between closed-crown boreal forests and northern open woodlands in the province of Quebec (Canada). The dataset consists of 875 plots spread across a 242 000 [km.sup.2] territory that ranges from the eastern to the western extremities of the province. The biomass of fruticose epiphytic lichens (Alectoria, Bryoria, Evernia, and Usnea) was evaluated at the branch, tree, and plot levels, and terricolous lichen cover (Cladonia spp.) was evaluated at the plot level. The results indicate that epiphytic and terricolous lichens respond significantly but differently to variations in forest characteristics. At the plot level, epiphytic lichen biomass was highest in the oldest stands (>100 years) and lowest in stand with low canopy cover (40%) or stands of intermediate age (60 to 100 years old). Species composition of epiphytic communities was also examined, and some species or genera exhibit a strong association with older stands (Alectoria sarmentosa (Ach.) Ach., Bryoria spp.) or with specific regions along the ca. 1500 km east-west gradient (Evernia mesomorpha Nyl. in the western part, Bryoria spp. in the central part, and A sarmentosa in the eastern part). In terms of conservation, these results indicate that epiphytic lichens communities are potentially sensitive to the preferential logging of older stands. Both epiphytic and terricolous lichen communities are also potentially sensitive to expected climate change effects such as increased fire frequencies or increased forest growth. Key words: lichen, boreal forest, epiphytes, Bryoria, Cladonia. Les principaux facteurs qui determinent la composition des communautes de lichens sont encore mal connus dans les ecosystemes boreaux nordiques. Cette etude compare les effets des caracteristiques (hauteur, couvert forestier et age) des peuplements forestiers sur les communautes de lichens epiphytes fruticuleux et terricoles a travers une vaste region situee a la limite ente les forets boreales a couvert ferme et les forets nordiques ouvertes dans la province de Quebec (Canada). Le jeu de donnees est compose de 875 placettes reparties sur un territoire de 242 000 [km.sup.2] qui s'etend entre les extremites est et ouest de la province. La biomasse des lichens epiphytes fruticuleux (Alectoria, Bryoria, Evernia et Usnea) a ete evaluee a l'echelle de la branche, de l'arbre et de la placette; le recouvrement de lichens terricoles (Cladonia spp.) a ete evalue a l'echelle de la placette. Les resultats montrent que les lichens epiphytes et terricoles reagissent de facon significative mais differente aux variations des caracteristiques de la foret. A l'echelle de la placette, la biomasse des lichens epiphytes etait la plus elevee dans les plus vieux peuplements (>100 ans), et la plus faible dans les peuplements avec un faible couvert forestier (40 %) ou dans les peuplements d'age intermediaire (60-100 ans). La composition en especes des communautes epiphytes a egalement ete etudiee et certaines especes ou genres etaient etroitement associes aux peuplements plus vieux (Alectoria sarmentosa (Ach.) Ach., Bryoria spp.), ou a des regions particulieres le long du gradient est-ouest d'environ 1500 km (Evernia mesomorpha Nyl. a l'ouest, Bryoria spp. au centre et A. sarmentosa a l'est). En termes de conservation, ces resultats indiquent que les communautes de lichens epiphytes sont potentiellement sensibles a l'exploitation preferentielle des vieux peuplements. Les communautes de lichens epiphytes et terricoles sont aussi potentiellement sensibles aux effets apprehendes des changements climatiques tels que l'augmentation de la frequence des feux ou l'augmentation de la croissance de la foret. [Traduit par la Redaction] Mots-cles: lichen, foret boreale, epiphytes, Bryoria, Cladonia., Introduction The northern boreal zone is at the transition between the closed-crown boreal forest (to the south) and the open taiga (to the north). In North America, this ecosystem is [...]