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1. Peatlands have suffered great losses following drainage for agriculture, forestry, urbanisation, or peat mining, near inhabited areas. We evaluated the faunal and vegetation patterns after restoration of a peatland formerly mined for peat. We assessed whether bog pools created during restoration are similar to natural bog pools in terms of water chemistry, vegetation structure and composition, as well as amphibian and arthropod occurrence patterns. 2. Both avian species richness and peatland vegetation cover at the site increased following restoration. Within bog pools, however, the vegetation composition differed between natural and man-made pools. The cover of low shrubs, Sphagnum moss, submerged, emergent and floating vegetation in man-made pools was lower than in natural pools, whereas pH was higher than in typical bog pools. Dominant plant species also differed between man-made and natural pools. 3. Amphibian tadpoles, juveniles and adults occurred more often in man-made pools than natural bog pools. Although some arthropods, including Coleoptera bog specialists, readily colonised the pools, their abundance was two to 26 times lower than in natural bog pools. Plant introduction in bog pools, at the stocking densities we applied, had no effect on the occurrence of most groups. 4. We conclude that our restoration efforts were partially successful. Peatland-wide vegetation patterns following restoration mimicked those of natural peatlands, but 4 years were not sufficient for man-made pools to fully emulate the characteristics of natural bog pools.

Bogs, or ombrotrophic peatlands, are well represented in parts of southeastern Canada but are subjected to increasing pressure from the peat industry. We assessed the impact of peat mining on small mammals inhabiting unexploited bog fragments on the periphery of mined bogs. We conducted two separate studies in bogs mined to different levels (0–83%) in southeastern Québec and New Brunswick. The first study used a low sampling effort over 1 month in 26 bogs, while the second used a high sampling effort of 6 months spread across 2 years in 12 bogs. Of the 15 small-mammal species encountered, only 2 were bog specialists. Abundance and species richness of small mammals in bog fragments increased significantly with percentage of area mined and, in some cases, increased with bog area. Both studies suggest that disturbances resulting from peat mining facilitate the invasion of more generalized small-mammal species. Furthermore, small mammals were more abundant near forest or mined edges than at bog centers, and some species responded strongly to vegetation cover. The response of small mammals to peat mining contrasts with the one documented for birds, amphibians, and plants., Les bogs, ou tourbières ombrotrophes, recouvrent une partie importante du sud-est canadien. Ils subissent toutefois des pressions croissantes de l’industrie de la tourbe. Nous avons évalué l’impact de l’exploitation de bogs sur les petits mammifères occupant des fragments naturels situés en périphérie de bogs exploités. Nous avons effectué deux études distinctes dans des bogs soumis à différents degrés d’exploitation (0–83 %) au Québec et au NouveauBrunswick. La première comportait un effort d’échantillonnage restreint à 1 mois dans 26 bogs, et la deuxième, plus intensive, portait sur 6 mois d’échantillonnage répartis sur 2 ans dans 12 bogs. Quinze espèces de petits mammifères ont été capturées, dont 2 spécialistes des tourbières. Dans les fragments naturels en périphérie de bogs exploités, la richesse en espèces et l’abondance de petits mammifères augmentaient en fonction de l’importance de la surface exploitée du bog, et dans certains cas, avec la superficie du bog. Les deux études indiquent que l’exploitation des bogs favorise l’invasion de petits mammifères d’espèces généralistes. De plus, les petits mammifères étaient plus abondants près des bordures exploitées et forestières. Certaines espèces étaient également influencées par la structure de la végétation. La réaction des petits mammifères à l’exploitation des bogs diffère de celle rapportée pour les oiseaux, les amphibiens et les plantes.

The study of migratory songbird transition periods, such as the post-breeding period, is complex because birds undertake different types of movements that vary in space and time. Nonetheless, it is important to understand the extent and duration of the territory and specific sites use to identify human activities likely to affect the species’ survival. Individuals from different regional populations may exhibit specific movements during the various phases of their annual cycle, and therefore conservation actions must be adapted. We studied a population of Canada Warblers (Cardellina canadensis) from the Saguenay region of Quebec, Canada, in the northeastern part of the species’ breeding range. We used a coordinated radio-telemetry network (Motus) to determine the residence time within the breeding territory, dates and times of departure, and early fall migration routes of 18 adult birds. We expected individuals to leave by mid-August and to migrate through the eastern flyway, along the Atlantic Coast. Six tracked individuals remained on their breeding territory until early September, corresponding to a residence time of approximately 90 days. These individuals left just after sunset on their day of departure. Twelve individuals departed earlier, and in the daytime, before the end of August; their earlier departure was likely for a purpose other than migration. Nine individuals were detected outside their breeding territory along the Atlantic migratory flyway: four migrated through the Great Lakes region, one in the Great Appalachian Valley, three along the Atlantic Coast or coastal plain, and one with an undetermined route. Our results suggest that adult Canada Warblers remain in the Saguenay region longer than expected, and that, although some individuals remain close to their breeding territory during the post-breeding period, others may use surrounding territories prior to initiating their fall migration. Our results will allow regional conservation ma

Migratory connectivity is the degree to which populations are linked in space and time across the annual cycle. Low connectivity indicates mixing of populations while high connectivity indicates population separation in space or time. High migratory connectivity makes individual populations susceptible to local environmental conditions; therefore, evaluating migratory connectivity continuously across a species range is important for understanding differential population trends and revealing places and times contributing to these differences. The common nighthawk Chordeiles minor is a widespread, declining, long‐distance migratory bird. Variable population trends across the nighthawk breeding range suggest that knowledge of migratory connectivity is needed to direct conservation. We used GPS tags to track 52 individuals from 12 breeding populations. We estimated migratory connectivity as 0.29 (Mantel coefficient: 0 = no connectivity, 1 = full connectivity) between the breeding and wintering grounds. We then estimated migratory connectivity at every latitude (spatial connectivity) or day (temporal connectivity) of migration and smoothed those migratory connectivity estimates to produce continuous migratory connectivity ‘profiles'. Spatial and temporal connectivity were highest during migration through North America (around 0.3–0.6), with values generally around 0 in Central and South America due to mixing of populations along a common migratory route and similar migration timing across populations. We found local peaks in spatial and temporal connectivity during migration associated with crossing the Gulf of Mexico. We used simulations to estimate the probability that our method missed peaks (spatial: 0.12, temporal: 0.18) or detected false peaks (spatial: 0.11, temporal: 0.37) due to data gaps and showed that our approach remains useful even for sparse and/or sporadic location data. Our study presents a generalizable approach to evaluating migratory connectivity acro

Many migratory species are declining and for most, the proximate causes of their declines remain unknown. For many long-distance Neotropical migratory songbirds, it is assumed that habitat loss on breeding or non-breeding grounds is a primary driver of population declines. We integrated data collected from tracking technology, community science and remote sensing data to quantify migratory connectivity (MC), population trends and habitat loss. We quantified the correlation between forest change throughout the annual cycle and population declines of a long-distance migratory songbird, the Connecticut warbler (Oporornis agilis, observed decline: −8.99% yr−1). MC, the geographic link between populations during two or more phases of the annual cycle, was stronger between breeding and autumn migration routes (MC = 0.24 ± 0.23) than between breeding and non-breeding locations (MC = −0.2 ± 0.14). Different Connecticut warbler populations tended to have population-specific fall migration routes but overlapped almost completely within the northern Gran Chaco ecoregion in South America. Cumulative forest loss within 50 km of breeding locations and the resulting decline in the largest forested patch index was correlated more strongly with population declines than forest loss on migratory stopover regions or on wintering locations in South America, suggesting that habitat loss during the breeding season is a driver of observed population declines for the Connecticut warbler. Land-use practices that retain large, forested patches within landscapes will likely benefit breeding populations of this declining songbird, but further research is needed to help inform land-use practices across the full annual cycle to minimize the impacts to migratory songbirds and abate ongoing population declines.

Les suivis démographiques d'espèces animales réalisés dans des sites stratégiques permettent de détecter les cas problématiques en matière de gestion et de conservation de la faune. L'Observatoire d'oiseaux de Tadoussac, situé dans le parc national du Saguenay, est une organisation ornithologique qui recueille, depuis 1993, des données sur les oiseaux de proie et les passereaux de la forêt boréale, particulièrement sur des espèces en difficulté. On présente ici cinq séries de données, obtenues à l'Observatoire d'oiseaux de Tadoussac, qui illustrent les tendances démographiques de quelques représentants de l'avifaune québécoise et qui mettent en évidence certains cycles de population.