Bichet Orphé, Dupuch Angélique, Hébert Christian, Le Borgne Hélène Le, Fortin Daniel
Ecol Appl. 2016 Mar;26(2):612-23. doi: 10.1890/15-0525.
With the intensification of human activities, preserving animal populations is a contemporary challenge of critical importance. In this context, the umbrella species concept is appealing because preserving a single species should result in the protection of multiple co-occurring species. Practitioners, though, face the task of having to find suitable umbrellas to develop single-species management guidelines. In North America, boreal forests must be managed to facilitate the recovery of the threatened boreal caribou (Rangifer tarandus). Yet, the effect of caribou conservation on co-occurring animal species remains poorly documented. We tested if boreal caribou can constitute an effective umbrella for boreal fauna. Birds, small mammals, and insects were sampled along gradients of post-harvest and post-fire forest succession. Predictive models of occupancy were developed from the responses of 95 species to characteristics of forest stands and their surroundings. We then assessed the similarity of species occupancy expected between simulated harvested landscapes and a 90 000-km2 uncut landscape. Managed landscapes were simulated based on three levels of disturbance, two timber-harvest rotation cycles, and dispersed or aggregated cut-blocks. We found that management guidelines that were more likely to maintain caribou populations should also better preserve animal assemblages. Relative to fragmentation or harvest cycle, we detected a stronger effect of habitat loss on species assemblages. Disturbing 22%, 35%, and 45% of the landscape should result, respectively, in 80%, 60%, and 40% probability for caribou populations to be sustainable; in turn, this should result in regional species assemblages with Jaccard similarity indices of 0.86, 0.79, and 0.74, respectively, relative to the uncut landscape. Our study thus demonstrates the value of single-species management for animal conservation. Our quantitative approach allows for the evaluation of management guidelines prior to implementation, thereby providing a tool for establishing suitable compromises between economic and environmental sustainability of human activities.
随着人类活动的加剧，保护动物种群成为一项至关重要的当代挑战。在此背景下，伞护种概念颇具吸引力，因为保护单一物种应能带来对多种共生物种的保护。然而，从业者面临着必须找到合适的“保护伞”以制定单物种管理准则的任务。在北美，北方森林必须进行管理以促进受威胁的北方驯鹿（Rangifer tarandus）种群的恢复。然而，驯鹿保护对共生动物物种的影响仍鲜有记录。我们测试了北方驯鹿是否能成为北方动物群的有效伞护种。沿着采伐后和火灾后的森林演替梯度对鸟类、小型哺乳动物和昆虫进行了采样。根据95个物种对林分及其周边环境特征的反应建立了占有率预测模型。然后，我们评估了模拟采伐景观与90000平方公里未砍伐景观之间预期的物种占有率相似性。基于三种干扰水平、两个木材采伐轮伐期以及分散或聚集的采伐区块模拟了管理景观。我们发现，更有可能维持驯鹿种群数量的管理准则也应能更好地保护动物群落。相对于破碎化或采伐周期，我们检测到栖息地丧失对物种群落有更强的影响。分别干扰景观的22%、35%和45%，应会使驯鹿种群可持续的概率分别为80%、60%和40%；相应地，相对于未砍伐景观，这应会导致区域物种群落的杰卡德相似性指数分别为0.
