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Rabies propagation in Canada has forced wildlife managers to develop intervention strategies to reduce the risk of rabies epizootics. We assessed whether some landscape characteristics of a corn-dominated region of Quebec in which the raccoon variant of rabies (RVR) has spread were associated with the abundances of raccoons ( Procyon lotor (L., 1758)) and striped skunks (Mephitis mephitis (Schreber, 1776)). We then examined whether landscape variables that best explained spatial variation in raccoon abundance were also good predictors in the detection of rabid raccoons. Between June and September 2007, 9600 raccoons and 1612 skunks were captured from 111 trapping cells. The abundance of captured raccoons, especially that of adult males and juveniles, increased over the summer in trapping cells characterized by a high density of forest edges bordering corn fields. The probability of detecting rabid raccoons also increased with this landscape characteristic, as well as with adult raccoon abundance. No landscape characteristic, however, explained spatial variation in skunk abundance. Efficient RVR control operations in similar landscapes should ideally include widespread distribution of vaccine baits because of the general distribution of skunks, while also focusing on areas where forest patches intersperse with corn fields to target high concentrations of raccoons, particularly in late summer.

We undertook a gap analysis of how protected areas represent the tree-species diversity within the Canadian boreal forest, as measured from Forest Resource Inventory (FRI) maps. We used a new compilation of Forest Resource Inventory designed to support ecological analyses over large areas and across jurisdictional boundaries. The analysis was stratified into four analytical regions determined by terrestrial ecozones. We calculated the relative abundance of species within regions, developed rarity criteria, and evaluated the relative abundances and prevalence of rare species. We characterized representation gaps when the abundance of a tree species in protected areas within an analytical region differed markedly (by more than a factor of 2) from the expectation, calculated as the product of regional abundance and the proportional area protected. Most species were well represented in the most speciesdiverse region (n = 33), the Boreal Shield in eastern Canada, due apparently to a large number of relatively small protected areas in the southern part of the region. Some marked gaps existed in the more species-depauperate western zones, notably for montane conifers in the Boreal Plains. As is common for species abundance distributions, as few as five species accounted for 90% of total abundance in each zone. Relatively rare species were more numerous. Mostly associated with southern temperate or hemiboreal forests, these reached their highest prevalence and abundance in the managed forests of the Boreal Shield. Our work identified some gaps in representation in the protected areas network of Canada in western Canada, substantiates the use of species distribution mapping based on FRI data to inform conservation planning -including the identification of high conservation biodiversity elements for forest certification -and demonstrates the need for improved vegetation mapping in National Parks.Résumé : Nous avons entrepris une analyse de carence pour déterminer dans quelle mesure les aires protégées sont représentatives de la diversité des espèces d'arbres dans la forêt boréale canadienne à partir des cartes de l'Inventaire des ressources forestières (IRF). Nous avons utilisé une nouvelle compilation des cartes de l'IRF réalisée dans le but de faciliter les analyses écologiques sur de vastes superficies qui chevauchent les limites de juridiction. L'analyse a été stratifiée en quatre régions d'analyse définies par des écozones terrestres. Nous avons calculé l'abondance relative des espèces à l'intérieur des régions, élaboré des critères de rareté et évalué l'abondance relative et la prévalence des espèces rares. Nous avons caractérisé les carences dans la représentation lorsque l'abondance d'une espèce d'arbre dans des zones protégées situées dans une région visée par l'analyse diffère de façon marquée (plus du double) de la valeur espérée, calculée comme le produit de l'abondance régionale et de la proportion en zone protégée. La plupart des espèces sont bien représentées dans la région la plus riche en espèces (n = 33),...