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We compared the avifauna in two cities, Quebec (Canada) and Rennes (France), in order to define general responses of wildlife in an urban ecosystem. These cities have a similar urban structure that permits investigation along an urbanization gradient from downtown to rural residential areas. However, they are in opposite temperate climate and imbedded in a forested and an agricultural landscape, respectively. Plots ranging from 10 to 20 ha were surveyed in winter and spring by recording all birds seen or heard. Most plots could be located along a gradient according to proportions of vegetated open space. Both the Shannon-Wiener and Simpson indices of diversity indicated a pattern of increasing diversity from most to least urbanized areas in spring. Winter species diversity and richness was low in Quebec compared to Rennes, reflecting the much harsher winter conditions in Quebec. Breeding densities of House Sparrows (Passer domesticus) and European Starlings (Sturnus vulgaris) were quite similar in Quebec and Rennes, as were densities of European Blackbirds (Turdus merula) and its ecological equivalent in Quebec, the American Robin (Turdus migratorius). The type of surrounding landscape can not explain the variation of species numbers within the city. If we examine the urban environment as a new ecological system rather than a degraded environment, we can regroup birds in two major species groups: the omnivorous species adapted to the urban environment and its particular food resources such as garbage and the species that find, in the urban environment, resources which they normally exploit in their usual habitat.

Summary1. The species diversity of adjacent landscapes influences the conservation or restoration of several animal groups in urban areas, but the effect on birds is unclear. To address this question, we compared bird species richness (BSR) and community composition between periurban (area surrounding the town) and urban (suburban and centre areas) landscapes across three spatial scales. 2. At a large biogeographical scale (temperate and boreal climatic zone), relationships between the BSR of urban areas and their surrounding landscapes were examined in a meta-analysis of 18 published studies. In general, BSR was negatively correlated with latitude and urbanization. The BSR of suburban and centre landscapes correlated positively with the BSR of periurban landscapes. However, latitudinal effects were also involved, as BSR in urban and periurban landscapes declined as town latitude increased. Similarity indices were low (50%) between periurban and centre bird communities. 3. At a regional scale, we assessed winter bird data from several towns within three regions of temperate and boreal countries (western France, northern Finland and eastern Canada). The type of periurban landscape, number of inhabitants and town diameter did not affect BSR. BSR was similar between the cities of a given biogeographical area. Bird communities were more similar between similar habitat types of different cities than between different habitats of the same city. 4. At a local scale, we tested the influence of proximity to the periurban landscape on BSR in parks of western French towns of different size. Neither BSR nor community similarity changed in relation to the distance of the park from the periurban landscape. 5. Guild composition according to diet and feeding habitat did not vary between urban and periurban locations at regional or local scales. 6. We conclude that, at regional and local scales, urban bird communities are independent of the bird diversity of adjacent landscapes, and that local features are more important than surrounding landscapes in determining BSR. Whatever the biodiversity quality of the periurban landscape, site-specific actions such as shrub and tree planting, water restoration and increasing vegetation diversity can change bird diversity in towns and improve the quality of human-wildlife contacts.

Bird community response to both landscape‐scale and local (forest types) changes in forest cover was studied in three boreal mixed‐wood forest landscapes modified by different types of disturbances: (1) a pre‐industrial landscape where human settlement, agriculture, and logging activities date back to the early 1930s, (2) an industrial timber managed forest, and (3) a forest dominated by natural disturbances. Birds were sampled at 459 sampling stations distributed among the three landscapes. Local habitat and landscape characteristics of the context surrounding each sampling station (500‐m and 1‐km radius) were also computed. Bird communities were influenced by landscape‐scale changes in forest cover. The higher proportion of early‐successional habitats in both human‐disturbed landscapes resulted in significantly higher abundance of early‐successional bird species and generalists. The mean number of mature forest bird species was significantly lower in the industrial and pre‐industrial landscapes than in the natural landscape. Landscape‐scale conversion of mature forests from mixed‐wood to deciduous cover in human‐disturbed landscapes was the main cause of changes in mature forest bird communities. In these landscapes, the abundance of species associated with mixed and coniferous forest cover was lower, whereas species that preferred a deciduous cover were more abundant. Variation in bird community composition determined by the landscape context was as important as local habitat conditions, suggesting that predictions on the regional impact of forest management on songbirds with models solely based on local scale factors could be misleading. Patterns of bird species composition were related to several landscape composition variables (proportions of forest types), but not to configuration variables (e.g., interior habitat, amount of edge). Overall, our results indicated that the large‐scale conversion of the southern portion of the boreal forest from a mixed to a deciduous cover may be one of the most important threats to the integrity of bird communities in these forest mosaics. Negative effects of changes in bird communities could be attenuated if current forestry practices are modified toward maintaining forest types (deciduous, mixed‐wood, and coniferous) at levels similar to those observed under natural disturbances.

Comparisons of the effects of logging and fire as disturbance agents on the composition of bird assemblages in boreal ecosystems are still lacking or are limited to the short-term impacts of clear-cutting. In Quebec, where the boreal forest is largely dominated by black spruce (Picea mariana (Mill.) B.S.P.) stands, we surveyed 140 point-count stations in 3 postlogging and 4 postfire development stages determined according to the height of the regenerating spruce trees. Species richness did not vary among forest development stages, but bird abundance was higher in recent clearcuts. Recently disturbed areas were characterized by open-land bird assemblages dominated by Neotropical migrants, which reached their highest abundance in clearcuts. Moreover, logged stands were distinguished from burned sites by the absence of cavity-nesting birds. Forest-bird assemblages reestablished themselves as soon as young spruces reached the sapling stage. However, the Black-backed Woodpecker (Picoides arcticus), Three-toed Woodpecker (Picoides tridactylus), and Brown Creeper (Certhia americana) were restricted to mature stands or recent burns and are thus likely to be negatively affected by modern forestry, which involves fire suppression and short logging rotations. We suggest that retention of larger areas of continuous mature forest might be essential to maintain these species in managed regions.

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ABSTRACT. Arctic communities are recently reporting warmer and shorter winters, which have implications for the ice season and, consequently, on the access to local territories and resources by members of these communities. These climatic shifts are resulting in increased risks for travel during the winter season associated with less stable and thinner ice. An integrated communitybased monitoring (ICBM) program was developed in Nunavik to generate adaptation tools to support safe access to land and resources and to enhance local adaptive capacity through participation in community-based monitoring activities. The Nunavik ICBM approach brings together partners (northern communities, Canadian universities, and various organizations) that have different perspectives on the issues surrounding land and resources in Nunavik. The ICBM project also brings together traditional knowledge and scientific knowledge, linking data collected through semi-structured interviews, local ethnocartographic interviews, and ice-monitoring activities with data gathered at weather stations. The partnership-based Nunavik ICBM program dealing with territory and resource access is an example of communities and scientists working together to improve our understanding of climate change impacts in the North, their importance for aboriginal people, and the ways in which an integrated, cooperative research process can develop local adaptive capacity.Key words: adaptation, climate change, ice monitoring, integrated community-based monitoring, semi-structured interviews, northern Quebec, scientific knowledge, traditional knowledge RÉSUMÉ. Les communautés arctiques rapportent depuis quelques années des hivers plus chauds et plus courts qui ont des implications sur la saison de glace et par conséquent sur l'accès au territoire et aux ressources locales par les membres de ces communautés. Ces conditions climatiques ont comme conséquence d'augmenter les risques lors des voyages hivernaux en raison de glaces instables et plus minces. Un programme intégré de surveillance des glaces (PISG) a été développé au Nunavik pour produire des outils d'adaptation visant à soutenir l'accès sécuritaire au territoire et aux ressources et pour augmenter la capacité d'adaptation locale par la participation communautaire aux activités de surveillance. L'approche du PISG rassemble plusieurs partenaires (les communautés nordiques, universités canadiennes et différents organismes) qui s'intéressent particulièrement aux questions d'accès au territoire et aux ressources au Nunavik et y apportent des perspectives variées. Le projet du PISG intègre le savoir traditionnel et le savoir scientifique utilisant plusieurs sources de données (provenant des entrevues semi-structurées, des entrevues ethno-cartographiques locales, de la surveillance de glace et des données météorologiques). Le PISG est un exemple de partenariat entre les communautés nordiques et les scientifiques qui permet de mieux comprendre les impacts des changements climatiques en cours dans le nord, leur importanc...

Sustainable harvest, the extraction of game without affecting population viability, is a desirable approach to the use of wildlife. However, overharvest has been responsible for the decline of many wildlife populations globally, so there is an urgent need to balance human requirements while avoiding the severe depletion of wild populations. Northern common eiders Somateria mollissima borealis are heavily hunted in Canada and Greenland, but the effect of this intensive harvest has not been examined. We developed a population model to investigate the sustainability of the reported harvest, which consisted of two wintering areas in Greenland and Atlantic Canada and three breeding populations. The model indicated that harvest in Atlantic Canada was sustainable, but a number of conditions could lead to slow declines. In contrast, the annual winter harvest of 55,000–70,000 eiders reported during 1993–2000 in Greenland was not sustainable, and this conclusion held under a wide range of alternate conditions. The model indicated that harvest during late winter may have a greater effect on populations than harvest in early winter. We further refined the model to assume that at some low population level the success of hunters would decline and that harvest became a function of population size (a rate). This scenario had the expected and undesirable result of stabilizing populations at very low levels. Overall, our model suggests that the high harvest reported in Greenland during 1993–2000 endangers the sustainable use of the northern common eider population and that management actions are required. Common eider harvest levels in Greenland should be reduced by at least 40% of the 1993–2000 levels to stop projected declines, and allow for recovery of the decimated Greenland breeding population. Encouragingly, new hunting regulations were introduced in Greenland in 2002–2004, and harvest levels appear to be decreasing. If these harvest reductions continue, our population model could be used to re‐evaluate the status of populations in the two countries.