Fatal Attraction? Intraguild Facilitation and Suppression among Predators
Fatal Attraction? Intraguild Facilitation and Suppression among Predators
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致命的吸引力？
DOI：
10.1086/693996
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Prugh, Laura R.
中科院分区：
文献类型：
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作者：
Sivy, Kelly J.;Pozzanghera, Casey B.;Grace, James B.;Prugh, Laura R.
竞争和压制被认为是构建捕食者群落的主导力量。然而，通过腐肉供应的促进作用是捕食者之间普遍存在的相互作用，可以抵消抑制的强度。了解这些积极和消极的相互作用的相对重要性是必要的，以预测全世界的顶级捕食者下降和复苏的社区范围内的反应。使用阿拉斯加州政府资助的狼（Canis lupus）控制作为准实验，我们对顶级，中型和小型捕食者进行了雪迹调查，以测试食肉动物级联的证据（例如，mesopredator release）。我们分析了调查数据，使用综合占用和结构方程建模框架来量化假设的相互作用途径的优势，我们评估了细尺度的时空响应nonapex捕食者狼的活动集群从无线电项圈数据。相反的食肉动物级联假说，中型和小型捕食者的占用模式表示公会范围内，负响应nonapex捕食狼丰度的变化在景观尺度。然而，在当地的规模，我们观察到一个近公会范围内，积极的反应nonapex掠食者本地化狼的活动。当地规模的协会与顶端捕食者，由于清除可能导致景观格局的中捕食者抑制，这表明在不同的空间尺度上的占用模式和捕食者群落结构之间的关键联系。
Competition and suppression are recognized as dominant forces that structure predator communities. Facilitation via carrion provisioning, however, is a ubiquitous interaction among predators that could offset the strength of suppression. Understanding the relative importance of these positive and negative interactions is necessary to anticipate community-wide responses to apex predator declines and recoveries worldwide. Using state-sponsored wolf (Canis lupus) control in Alaska as a quasi experiment, we conducted snow track surveys of apex, meso-, and small predators to test for evidence of carnivore cascades (e.g., mesopredator release). We analyzed survey data using an integrative occupancy and structural equation modeling framework to quantify the strengths of hypothesized interaction pathways, and we evaluated fine-scale spatiotemporal responses of nonapex predators to wolf activity clusters identified from radio-collar data. Contrary to the carnivore cascade hypothesis, both meso- and small predator occupancy patterns indicated guild-wide, negative responses of nonapex predators to wolf abundance variations at the landscape scale. At the local scale, however, we observed a near guild-wide, positive response of nonapex predators to localized wolf activity. Local-scale association with apex predators due to scavenging could lead to landscape patterns of mesopredator suppression, suggesting a key link between occupancy patterns and the structure of predator communities at different spatial scales.