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Natural forests will likely be unable to sustainably fulfill society needs for wood fibers and intensively managed plantations could be an alternative source of timber in the future. Abandoned farm fields are often targeted for conversion, as they are already disturbed sites; however, they also represent high-quality habitat for species such as snowshoe hares (Lepus americanus Erxleben 1777), a keystone mammal in the boreal forest. We evaluated the effect of converting abandoned farm fields (n = 22) to conifer plantations (n = 19) on habitat use by snowshoe hares, using pellet counts and snow-tracking surveys. Both survey techniques yielded similar results: winter habitat use by hares is mostly affected by vegetation cover rather than habitat type. In the short term, plantations do not offer less protective cover than the one found in abandoned farm fields. However, upon reaching a certain height (>=7 m), plantations are mechanically pruned and lose their protective quality. Promoting silvicultural techniques that maintain lateral cover beyond a critical threshold (70%) could preserve the quality of hare habitat for an extended proportion of rotation time of the plantation. Il est vraisemblable que les forêts naturelles ne puissent pas combler de façon durable les besoins de la société pour les fibres de bois et que des plantations intensives servent alors de sources de replacement de bois dans le futur. Les champs de ferme abandonnés sont souvent visés pour la conversion en plantation, car ce sont des sites déjà perturbés; ils représentent toutefois un habitat de grande qualité pour des espèces comme le lièvre d’Amérique (Lepus americanus Erxleben, 1777), un mammifère clé de la forêt boréale. Nous avons évalué l’effet de la conversion de champs de ferme abandonnés (n = 22) en plantations de conifères (n = 19) sur l’utilisation de l’habitat par le lièvre d’Amérique en utilisant le décompte de fèces et les inventaires de pistes sur la neige. Les deux techniques d’inventaire donnent des résultats similaires : l’utilisation de l’habitat en hiver par les lièvres est plus affectée par le couvert protecteur que par le type d’habitat. À court terme, les plantations n’offrent pas moins de couvert protecteur que les champs de ferme abandonnés. Cependant, lorsqu’elles ont atteint une certaine taille (>=7 m), les plantations sont émondées mécaniquement et perdent leur propriété protectrice. La promotion de techniques de sylviculture qui laisseraient la couverture latérale au-delà d’un seuil critique (70 %) pourrait préserver la qualité de l’habitat du lièvre pendant une portion étendue de la période de rotation de la plantation. [ABSTRACT FROM AUTHOR]

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Habitat-selection analysis involves a comparison between the proportions of different cover types that are used by the animal and the proportions that are available. Telemetry locations or animal occurrences (e.g., from aerial surveys) can provide information on habitat utilization. With telemetry data, a classical approach involves computing habitat use at the individual location sites or inside fixed circle buffers applied to the sites. We used this approach (200 m radius circles) on data from a systematic aerial survey on Anticosti Island, where 260 groups of white-tailed deer (Odocoileus virginianus) (374 animals) were counted in a 270-km² block. We compared the selection indices obtained from site occurrences with those of two approaches that define areas of high intensity (animal concentrations): 50% fixed kernels (0.5-2 km bandwidth) and the local K function (0.5-2 km distance). The results were very consistent among the three sets of approaches, with the same cover types generally identified as those having the highest or lowest indices. White-tailed deer preferred forest stands where balsam fir (Abies balsamea) was present as high regeneration or was dominant in the tree layer (>50% basal area) and stands at the regeneration stage. In the studied landscape, there seems to be a wide range of spatial scales where the selection process can be analyzed from aerial survey data. [ABSTRACT FROM AUTHOR]