Data from: Testing the link between perceived and actual risk of predation: mosquito oviposition site selection and egg predation by native and introduced fish

1. According to the threat-sensitivity hypothesis, prey avoidance behaviour should reflect the magnitude of predation risk. Since predation can strongly affect reproduction success, ovipositing females are expected to adaptively adjust their predator-avoidance response, or local breeding patch selectivity, in accordance with the perceived level of threat posed for their progeny by specific predators. However, association between avoidance and predation can be disrupted when the prey and the predator lack spatio-temporal opportunities to co-evolve, such as in cases of non-native predator introductions. 2. We examined the interactions between mosquitoes (from the genus Culex) and three species of sympatric predaceous freshwater fish, a native cyprinid (Barbus paludinosus), a cichlid (Pseudocrenilabrus philander), and an introduced poeciliid, the Western mosquitofish (Gambusia affinis). 3. In an outdoor mesocosm experiment we quantified patterns of Culex oviposition site selection across fish species using free-roaming, caged, and fish-free treatments. In a complementary laboratory experiment we tested the effectiveness of each fish species as predators of mosquito eggs and larvae. 4. Synthesis and applications. We found evidence for: (i) mosquito egg raft predation by free- roaming fish; (ii) fish-specific avoidance by ovipositing Culex and (iii) a positive association between fish-specific oviposition avoidance and fish-specific efficiency as an egg predator. These results contribute towards a better understanding of predator-prey coevolution, predator-borne cue recognition, and suggest local native fish, the Southern mouthbrooder (Pseudocrenilabrus philander), as an alternative to Gambusia for the biocontrol of Culex mosquitoes.

1. 根据威胁敏感性假说（threat-sensitivity hypothesis），猎物的避敌行为应反映捕食风险的高低。由于捕食作用会显著影响繁殖成功率，产卵雌蚊理应会依据特定捕食者对其后代造成的感知威胁水平，适应性调整自身的避敌反应或局部产卵位点选择性。然而，当猎物与捕食者缺乏时空共演化的机会时，避敌行为与捕食风险间的关联会被打破，例如在外来捕食者引入的场景中。
2. 本研究探究了库蚊属（Culex）蚊子与三种同域捕食性淡水鱼类的相互作用：包括本土鲤科鱼类（cyprinid）非洲小鲤（Barbus paludinosus）、慈鲷（cichlid）南方口孵慈鲷（Pseudocrenilabrus philander），以及引入的花鳉科鱼类（poeciliid）西部食蚊鱼（Gambusia affinis）。
3. 在室外中型实验生态系统实验（outdoor mesocosm experiment）中，我们通过设置自由活动、笼养及无鱼三种处理组，量化了库蚊在不同鱼类物种处理下的产卵位点选择模式。配套开展的实验室实验则检验了各鱼类物种对蚊卵和幼虫的捕食效能。
4. 综合与应用。本研究发现了以下证据：(i) 自由活动鱼类可捕食蚊卵块；(ii) 产卵库蚊会表现出鱼类特异性的避斥行为；(iii) 鱼类特异性产卵避斥与该鱼类作为卵捕食者的特异性捕食效率呈正相关关系。上述研究结果有助于深化对捕食者-猎物共演化、捕食者源性信号识别的认知，并表明本土鱼类南方口孵慈鲷（Pseudocrenilabrus philander）可作为西部食蚊鱼的替代方案，用于库蚊的生物防治。