Behavioral adjustments to predation risk not only impose costs on prey species themselves but can also have cascading impacts on whole ecosystems. The greater bilby (Macrotis lagotis) is an important ecosystem engineer, modifying the physical environment through their digging activity, and supporting a diverse range of sympatric species that use its burrows for refuge and food resources. The bilby has experienced a severe decline over the last 200 years, and the species is now restricted to ~20% of its former distribution. Introduced predators, such as the feral cat (Felis catus), have contributed to this decline. We used camera traps to monitor bilby burrows at four sites in Western Australia, where bilbies were exposed to varying levels of cat predation threat. We investigated the impact of feral cats on bilby behavior at burrows, particularly during highly vulnerable periods when they dig and clear away soil or debris from the burrow entrance as they perform burrow maintenance. There was little evidence that bilbies avoided burrows that were visited by a feral cat; however, bilbies reduced the time spent performing burrow maintenance in the days following a cat visit (P = 0.010). We found the risk posed to bilbies varied over time, with twice the cat activity around full moon compared with dark nights. Given bilby burrows are an important resource in Australian ecosystems, predation by feral cats and the indirect impact of cats on bilby behavior may have substantial ecosystem function implications.

中文翻译：

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做家务还是保持警惕？在野猫捕食的威胁下，兔耳袋狸改变了他们的洞穴活动

针对捕食风险的行为调整不仅会给被捕食物种本身带来成本，还会对整个生态系统产生连锁影响。大耳袋狸 (Macrotis lagotis) 是重要的生态系统工程师，通过挖掘活动改变自然环境，并支持各种利用其洞穴作为避难所和食物资源的同域物种。兔耳袋狸在过去 200 年里经历了严重的数量下降，目前该物种的分布范围仅限于以前的 20% 左右。引入的捕食者，例如野猫（Felis catus），导致了这种下降。我们使用摄像机陷阱来监测西澳大利亚四个地点的兔耳袋狸洞穴，这些地方的兔耳袋狸受到不同程度的猫捕食威胁。我们调查了野猫对洞穴中兔耳袋狸行为的影响，特别是在它们在进行洞穴维护时挖掘并清除洞穴入口处的土壤或碎片的高度脆弱时期。几乎没有证据表明兔耳袋狸会避开野猫出没的洞穴。然而，兔耳袋狸在猫拜访后的几天内减少了进行洞穴维护的时间（P = 0.010）。我们发现，兔耳袋狸所面临的风险随着时间的推移而变化，满月前后猫的活动量是黑夜的两倍。鉴于兔耳袋狸的洞穴是澳大利亚生态系统的重要资源，野猫的捕食以及猫对兔耳袋狸行为的间接影响可能会对生态系统功能产生重大影响。