| Summary: | We reviewed the literature reporting negative or positive effects on vegetation of herbivory by caribou/reindeer, moose, and white-tailed deer in light of the hypothesis of exploitation ecosystems (EEH), which predicts that most of the negative impacts will occur in areas where wolves were extirpated. We were able to list 197 plant taxa negatively affected by the three cervid species, as opposed to 24 that benefited from their herbivory. The plant taxa negatively affected by caribou/reindeer (19), moose (37), and white-tailed deer (141) comprised 5%, 9%, and 11% of vascular plants present in their respective ranges. Each cervid affected mostly species eaten during the growing season: lichens and woody species for caribou/reindeer, woody species and aquatics for moose, and herbs and woody species for white-tailed deer. White-tailed deer were the only deer reported to feed on threatened or endangered plants. Studies related to damage caused by caribou/reindeer were scarce and often concerned lichens. Most reports for moose and white-tailed deer came from areas where wolves were absent or rare. Among the three cervids, white-tailed deer might damage the most vegetation because of its smaller size and preference for herbs. À la lumière de l'hypothèse de l'exploitation des écosystèmes (EEH), nous avons examiné les publications qui mentionnent les effets négatifs ou positifs, sur la végétation, du broutement du caribou/renne, de l'orignal et du cerf de Virginie. Cette hypothèse prédit que les impacts négatifs se concentrent dans des endroits où le loup a été éliminé. Nous avons pu énumérer 197 taxons végétaux affectés négativement par les trois cervidés, contre 24 qui profitaient du broutement. Le nombre de taxons végétaux affectés négativement par le broutement du caribou/renne (19), de l'orignal (37) et du cerf de Virginie (141) représentait respectivement 5, 9 et 11 p. cent des plantes vasculaires situées dans les aires de répartition spécifiques des animaux. Chaque cervidé affectait surtout les espèces ...
|
|---|