Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Private Bag X20 Hatfield, Pretoria, 0028, South Africa.
Endangered Wildlife Trust, Private Bag X11, Johannesburg, 1609, South Africa.
Conserv Biol. 2019 Oct;33(5):1106-1119. doi: 10.1111/cobi.13299. Epub 2019 May 6.
As landscapes continue to fall under human influence through habitat loss and fragmentation, fencing is increasingly being used to mitigate anthropogenic threats and enhance the commercial value of wildlife. Subsequent intensification of management potentially erodes wildness by disembodying populations from landscape-level processes, thereby disconnecting species from natural selection. Tools are needed to measure the degree to which populations of large vertebrate species in formally protected and privately owned wildlife areas are self-sustaining and free to adapt. We devised a framework to measure such wildness based on 6 attributes relating to the evolutionary and ecological dynamics of vertebrates (space, disease and parasite resistance, exposure to predation, exposure to limitations and fluctuations of food and water supply, and reproduction). For each attribute, we set empirical, species-specific thresholds between 5 wildness states based on quantifiable management interventions. We analysed data from 205 private wildlife properties with management objectives spanning ecotourism to consumptive utilization to test the framework on 6 herbivore species representing a range of conservation statuses and commercial values. Wildness scores among species differed significantly, and the proportion of populations identified as wild ranged from 12% to 84%, which indicates the tool detected site-scale differences both among populations of different species and populations of the same species under different management regimes. By quantifying wildness, this framework provides practitioners with standardized measurement units that link biodiversity with the sustainable use of wildlife. Applications include informing species management plans at local scales; standardizing the inclusion of managed populations in red-list assessments; and providing a platform for certification and regulation of wildlife-based economies. Applying this framework may help embed wildness as a normative value in policy and mitigate the shifting baseline of what it means to truly conserve a species.
随着景观不断受到人类活动的影响，包括栖息地丧失和破碎化，围栏越来越多地被用于减轻人为威胁和提高野生动物的商业价值。随后，管理的强化可能会通过使种群脱离景观水平的过程而削弱野性，从而使物种与自然选择脱节。我们需要工具来衡量正式保护和私人拥有的野生动物区的大脊椎动物种群在多大程度上能够自我维持并自由适应。我们设计了一个框架，根据与脊椎动物的进化和生态动态相关的 6 个属性（空间、疾病和寄生虫抗性、捕食暴露、食物和水供应限制和波动的暴露、繁殖）来衡量这种野性。对于每个属性，我们根据可量化的管理干预措施，在 5 种野生状态之间设定了经验性的、特定物种的阈值。我们分析了 205 个具有从生态旅游到消费利用等不同管理目标的私人野生动物物业的数据，以测试该框架在 6 种食草动物物种上的应用，这些物种代表了一系列不同的保护状况和商业价值。物种间的野性评分差异显著，被确定为野生的种群比例从 12%到 84%不等，这表明该工具不仅可以检测不同物种的种群之间，而且可以检测同一物种在不同管理体制下的种群之间的站点尺度差异。通过量化野性，该框架为从业人员提供了将生物多样性与野生动物可持续利用联系起来的标准化测量单位。应用包括在地方尺度上为物种管理计划提供信息；标准化将管理种群纳入红色名录评估；并为基于野生动物的经济的认证和监管提供平台。应用该框架可能有助于将野性作为政策中的规范价值，并减轻真正保护物种的意义的基准转移。
