Data from: Pyric-carnivory: raptor use of prescribed fires

Fire is a process that shaped and maintained most terrestrial ecosystems worldwide. Changes in land use and patterns of human settlement have altered fire regimes and led to fire suppression resulting in numerous undesirable consequences spanning individual species and entire ecosystems. Many obvious and direct consequences of fire suppression have been well studied, but several, albeit less obvious, costs of alteration to fire regimes on wildlife are unknown. One such phenomenon is the response of carnivores to fire events—something we refer to as pyric-carnivory. To investigate the prevalence of pyric-carnivory in raptors, we monitored 25 prescribed fires occurring during two different seasons and across two different locations in tallgrass prairie of the central United States. We used paired point counts occurring before and during prescribed fires to quantify the use of fires by raptors. We found a strong attraction to fires with average maximum abundance nearly seven times greater during fires than prior to ignitions (before: x ̅ = 2.90, SE = 0.42; during: x ̅ = 20.20; SE = 3.29) and an average difference between fire events and immediately before fires of 15.2 (± 2.69) raptors. This result was driven by Swainson’s hawks (Buteo swainsoni), which were the most abundant (n = 346) of the nine species we observed using fires. Our results illustrate the importance of fire as integral disturbance process that effects wildlife behavior through multiple mechanisms that are often overshadowed by the predominant view of fire as a tool used for vegetation management.火是塑造并维持全球绝大多数陆地生态系统的核心过程。土地利用变化与人类定居模式改变已改写了火制度（fire regimes），并引发了火抑制（fire suppression）行为，进而引发了波及单个物种乃至整个生态系统的诸多不良后果。火抑制带来的诸多显性直接后果已得到充分研究，但火制度改变对野生动物产生的若干隐性代价仍未明晰。其中一类尚未明确的现象便是肉食动物对火事件的响应——我们将其定义为火相关肉食行为（pyric-carnivory）。为探究猛禽（raptors）中火相关肉食行为的普遍性，我们在美国中部高草草原（tallgrass prairie）的两处不同区域，针对两个不同季节开展的25次计划烧除（prescribed fires）进行了监测。我们采用火烧前后的配对样点调查（paired point counts）法，量化猛禽对火区的利用情况。研究发现猛禽对火区存在显著趋附性：火烧期间的平均最大种群丰度几乎是点火前的7倍（点火前：均值$ar{x}$=2.90，标准误（standard error, SE）=0.42；火烧期间：均值$ar{x}$=20.20，标准误（standard error, SE）=3.29），火烧期间与点火前的平均种群数量差值达15.2±2.69只猛禽。该结果主要由斯温氏鵟（Swainson’s hawk，Buteo swainsoni）驱动——在我们观测到的9种利用火区的猛禽中，斯温氏鵟的种群丰度最高（样本量n=346）。本研究结果表明，火作为一种不可或缺的干扰过程，可通过多种机制影响野生动物行为，但这一作用常被“火仅为植被管理工具”的主流观点所掩盖。