Le rôle des herbivores vertébrés sur la dynamique des communautés végétales au Nunavik

Environmental changes influence northern plant communities and the populations of herbivores that feed on them. Given the predicted increased rates of change in the north, it is essential to understand the situation in Nunavik (Québec, Canada). This review outlines the influence of vertebrate herbiv...

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Bibliographic Details
Published in:Le Naturaliste canadien
Main Authors: Ropars, Pascale, Simard, Martin, Boudreau, Stéphane
Format: Article in Journal/Newspaper
Language:French
Published: Société Provancher d'histoire naturelle du Canada 2020
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Online Access:https://doi.org/10.7202/1068216ar
http://id.erudit.org/iderudit/1068216ar
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Summary:Environmental changes influence northern plant communities and the populations of herbivores that feed on them. Given the predicted increased rates of change in the north, it is essential to understand the situation in Nunavik (Québec, Canada). This review outlines the influence of vertebrate herbivores on plant communities and describes the population status of the two main members of this guild in the region. The migratory caribou (Rangifer tarandus) is a keystone species, and two herds are present. At high densities, it can reduce plant productivity in its summer range and limit the growth of the species consumed. The muskox (Ovibos moschatus), which was introduced in the 1960s, has now colonized most of the region’s coastal area. Although it may limit shrub expansion elsewhere in the Arctic, to date, its influence in Nunavik remains marginal. Except for the Canada goose (Branta canadensis), which nests in large colonies, the impact of other vertebrate herbivores on plant communities is likely localized. Increases in shrub cover will provide food and shelter for various herbivores that may experience a northward shift in range. Finally, the food preferences of herbivores present in Nunavik is expected to influence the response of plant species to climate change. Les changements environnementaux influencent la végétation nordique, mais également les herbivores qui s’en nourrissent. Comme ces changements s’accentueront, un état de la situation au Nunavik (Québec, Canada) devient nécessaire. Nous discutons ici de l’influence qu’exercent les herbivores vertébrés sur les communautés végétales, et décrivons l’état des populations des deux principales espèces d’herbivores de cette guilde au Nunavik. Réparti en deux troupeaux, le caribou migrateur (Rangifer tarandus) est un élément structurant des écosystèmes du Nunavik. À forte densité, il peut réduire la productivité végétale dans son aire d’estivage et limiter la croissance des espèces consommées. Espèce introduite dans les années 1960, le boeuf musqué (Ovibos ...