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To describe the forest mosaic suitable for marten (  Martes americana) in a clearcut boreal landscape, we studied habitat selection in an area (123 km2) located in western Québec, in which black spruce (  Picea mariana) was the predominant forest type. This block had been recently clearcut with the protection of regeneration cutting technique, a logging method that employs equally spaced harvesting trails. The resulting landscape had a center dominated by a cutover matrix (60% of the block) and surrounded by contiguous uncut forest. Over 2 years, 20 marten equipped with radio collars provided enough locations to delineate their winter home range. Habitat composition and spatial configuration were measured at both stand and landscape scales by means of a geographic information system database that included telemetry locations and home ranges, forest maps, and limits of clearcut areas. Inside their winter home ranges, animals avoided open regenerating stands composed mostly of recent clearcuts with sparse regeneration. They did not select coniferous stands, even those that were mature or overmature, but preferred deciduous and mixed stands, a large proportion of which had a dense coniferous shrub layer as a result of a spruce budworm (Choristoneura fumiferana) epidemic 15–20 years ago. At the landscape scale, winter home ranges differed from random mosaics because they had a larger proportion of uncut forest (>30 years), a smaller proportion of open regenerating stands, larger core area in forest habitat, and less edge between open regenerating stands and forest. Winter home ranges usually contained <30–35% open or closed regenerating stands and> 40–50% uncut forest. We conclude that marten and clearcutting may be compatible, provided that forest logging is adapted to that species at the landscape level. Where the objective is to maintain marten at a local scale in black spruce forest, we suggest that ≥50% uncut forest be preserved inside 10‐km2 units and that <30% of the area be clearcut over a 30‐year period.

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Understory regeneration within canopy gaps in old-growth boreal forests may provide suitable habitat for wildlife typically associated with early-seral stages, leading to an increase in their abundance in late succession. We surveyed a chronosequence of postfire (17-265 years) and postharvest (3-63 years) stands in Canada's eastern boreal forest to determine whether snowshoe hares (Lepus americanus Erxleben, 1777) followed a bimodal abundance distribution with stand age that reflects changes in food and cover during postdisturbance succession. A strong peak in relative hare abundance occurred during the first 80 years of succession, with highest faecal pellet densities observed between 40 and 50 years after disturbance. Changes in hare abundance during this period were similar among fire-and clearcut-origin stands and closely tracked changes in lateral cover and vertical cover. Pellet density increased again in stands >180 years. Variation in hare abundance during late succession was partially mediated by gap dynamics, with highest pellet densities in stands occupied by an intermediate proportion of mortality-origin canopy gaps. Hares thus undergo rapid changes in abundance during early succession followed by a much longer period of subtle changes in density as stands develop old-growth structure. Shifting forest age-class distribution induced by forest management could therefore significantly alter regional spatiotemporal dynamics of snowshoe hares.Résumé : Une régénération arbustive importante à l'intérieur des trouées dans les forêts boréales anciennes peut fournir des conditions d'habitat favorables aux espèces animales typiques des jeunes forêts, menant ainsi à une augmentation de leur abondance en fin de succession. Nous avons échantillonné une chronoséquence de successions après feu (17-265 ans) et après coupe (3-63 ans) dans la forêt boréale de l'est du Canada pour évaluer l'hypothèse selon laquelle l'abondance du liè-vre d'Amérique (Lepus americanus Erxleben, 1777) suit une distribution bimodale en fonction de l'âge des peuplements qui reflèterait les changements de nourriture et de couvert qui ont lieu au cours de la succession. Un fort pic d'abondance relative du lièvre a lieu au cours des 80 premières années de succession, avec les densités de fèces de lièvre les plus élevées dans les peuplements de 40-50 ans après la perturbation. Les changements d'abondance du lièvre pendant cette période sont semblables dans les peuplements issus de coupe et de feu et suivent de près les changements de couvert latéral et vertical. L'abondance relative du lièvre augmente de nouveau dans les peuplements de >180 ans. Les variations d'abondance du lièvre dans les peuplements en fin de succession sont liées à la dynamique de trouées, avec les densités de crottins les plus élevées dans les peuplements ayant une proportion intermédiaire de trouées issues de mortalité. Le lièvre subit donc des changements d'abondance rapides en début de succession, suivis de changements moins prononcés au cours d'une période beaucoup plus ...

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