Predator responses to fire: A global systematic review and meta-analysis

1. Knowledge of how disturbances such as fire shape habitat structure and composition, and affect animal interactions, is fundamental to ecology and ecosystem management. Predators also exert strong effects on ecological communities, through top-down regulation of prey and competitors, which can result in trophic cascades. Despite their ubiquity, ecological importance and potential to interact with fire, our general understanding of how predators respond to fire remains poor, hampering ecosystem management. 2. To address this important knowledge gap, we conducted a systematic review and meta-analysis of the effects of fire on terrestrial, vertebrate predators worldwide. We found 160 studies spanning 1978–2018. There were 36 studies with sufficient information for meta-analysis, from which we extracted 96 effect sizes (Hedge's g) for 67 predator species relating to changes in abundance indices, occupancy or resource selection in burned and unburned areas, or before and after fire. 3. Studies spanned geographic locations, taxonomic families, and study designs, but most were located in North America and Oceania (59% and 24%, respectively), and largely focussed on felids (24%) and canids (25%). Half (50%) of the studies reported responses to wildfire, and nearly one third concerned prescribed fires. 4. There were no clear, general responses of predators to fire, nor relationships with geographic area, biome or life history traits (e.g. body mass and diet). Responses varied considerably between species. Analysis of species for which at least three effect sizes had been reported in the literature revealed that red foxes (Vulpes vulpes) mostly responded positively to fire (e.g. higher abundance in burned compared to unburned areas) and eastern racers (Coluber constrictor) negatively, with variances overlapping zero only slightly for both species. 5. Our systematic review and meta-analysis revealed strong variation in predator responses to fire, and geographic and taxonomic knowledge gaps. Varied responses of predator species to fire likely depend on ecosystem context. Consistent reporting of ongoing monitoring and management experiments is required to improve understanding of the mechanisms driving predator responses to fire, and any broader effects (e.g. trophic interactions). The divergent responses of species in our study suggest that adaptive, context-specific management of predator-fire relationships is required.

1. 了解火灾等干扰如何塑造栖息地结构与组成、影响动物间相互作用，是生态学与生态系统管理的基础。捕食者通过对猎物与竞争者的自上而下调控，也会对生态群落产生强烈影响，这可能引发营养级联（trophic cascades）。尽管捕食者普遍存在、具有重要生态意义且可能与火灾发生相互作用，但我们对捕食者如何响应火灾的整体认知仍较为匮乏，这阻碍了生态系统管理。2. 为填补这一关键知识空白，我们对全球范围内火灾对陆生脊椎动物捕食者的影响开展了系统综述与元分析。我们检索到1978–2018年间的160项研究，其中36项研究提供了足够信息用于元分析；从中我们提取了67种捕食者物种的96个效应量（Hedge's g），涉及火烧区与未火烧区、或火灾前后的丰度指数、占据率或资源选择的变化。3. 这些研究覆盖不同地理位置、分类阶元与研究设计，但多数位于北美洲与大洋洲（分别占59%与24%），且主要聚焦于猫科动物（24%）与犬科动物（25%）。半数（50%）研究报道了捕食者对野火的响应，近三分之一则涉及计划烧除（prescribed fires）。4. 捕食者对火灾并无明确的一般性响应模式，亦未发现其与地理区域、生物群系或生活史特征（如体重与食性）存在关联。物种间的响应差异显著。对文献中至少有三个效应量报道的物种分析显示：赤狐（Vulpes vulpes）对火灾多呈正向响应（如火烧区丰度高于未火烧区），而东部锦蛇（Coluber constrictor）则呈负向响应，且两者的方差仅轻微重叠于零值。5. 本系统综述与元分析揭示了捕食者对火灾响应的显著差异，以及地理与分类学层面的知识空白。捕食者物种对火灾的不同响应可能取决于生态系统背景。需持续报告正在进行的监测与管理实验，以加深对驱动捕食者火灾响应的机制及任何更广泛效应（如营养级相互作用）的理解。本研究中物种的分歧响应表明，需对捕食者-火灾关系采取适应性、情境特异性的管理策略。