The umbrella value of caribou management strategies for biodiversity conservation in boreal forests under global change

Single-species conservation management is often proposed to preserve biodiversity in human-disturbed landscapes. How global change will impact the umbrella value of single-species management strategies remains an open question of critical conservation importance. We assessed the effectiveness of threatened boreal caribou as an umbrella for bird and beetle conservation under global change. We combined mechanistic, spatially explicit models of forest dynamics and predator-prey interactions to forecast the impact of management strategies on the survival of boreal caribou in boreal forest. We then used predictive models of species occupancy to characterize concurrent impacts on bird and beetle diversity. Landscapes were simulated based on three scenarios of climate change and four of forest management. We found that strategies that best mitigate human impact on boreal caribou were an effective umbrella for maintaining bird and beetle assemblages. While we detected a stronger effect of land-use change compared to climate change, the umbrella value of management strategies for caribou habitat conservation were still impacted by the severity of climate change. Our results showed an interplay among changes in forest attributes, boreal caribou mortality, as well as bird and beetle species assemblages. The conservation status of some species mandates the development of recovery strategies, highlighting the importance of our study which shows that single-species conservation can have important umbrella benefits despite global change.

Methods
All the methods are detailed in the article: Labadie G. et al. The umbrella value of caribou management strategies for biodiversity conservation in boreal forests under global change.

在受人类活动干扰的景观中，单物种保护管理常被提出作为保护生物多样性的手段。然而，全球变化将如何影响单物种保护策略的伞护价值（umbrella value），仍是保护生物学领域具有重要保护意义的未解问题。本研究评估了全球变化背景下，受胁北方驯鹿（boreal caribou）作为鸟类与甲虫保护的伞护种（umbrella species）的实际效果。研究结合森林动态与捕食者-猎物相互作用的机制性空间显式模型（spatially explicit model），预测各类保护管理策略对北方森林中北方驯鹿种群存续的影响；随后通过物种占用预测模型（species occupancy model），量化分析该类管理策略对鸟类与甲虫多样性的同步影响。本研究基于3种气候变化情景与4种森林管理情景对研究景观进行模拟。结果显示，能够最有效减缓人类活动对北方驯鹿负面影响的管理策略，同时可有效维持鸟类与甲虫的群落结构。尽管研究发现土地利用变化对生物多样性的影响强于气候变化，但用于保护驯鹿栖息地的管理策略的伞护价值，仍会受到气候变化强度的影响。本研究结果揭示了森林属性变化、北方驯鹿死亡率以及鸟类与甲虫群落组成三者间的相互作用关系。部分物种的保护现状亟需制定针对性恢复策略，这凸显了本研究的重要价值：即便在全球变化背景下，单物种保护仍能带来显著的伞护效益。

方法
所有研究方法详见论文：Labadie G. 等. 全球变化背景下驯鹿管理策略对北方森林生物多样性保护的伞护价值。