Data from: The behavioral type of a top predator drives the short-term dynamic of intraguild predation

Variation in behavior among individual top predators (i.e., the behavioral type) can strongly shape pest suppression in intraguild predation (IGP). However, the effect of a top predator’s behavioral type—namely, foraging aggressiveness (number of killed divided by prey time) and prey choosiness (preference degree for certain prey type)—on the dynamic of IGP may interact with the relative abundances of top predator, mesopredator, and pest. We investigated the influence of the top predator’s behavioral type on the dynamic of IGP in a three-species system with a top predator spider, a mesopredator spider, and a psyllid pest using a simulation model. The model parameters were estimated from laboratory experiments and field observations. The top predator’s behavioral type altered the food-web dynamics in a context-dependent manner. The system with an aggressive/nonchoosy top predator, without prey preferences between pest and mesopredator, suppressed the pest more when the top predator to mesopredator abundance ratio was high. In contrast, the system with a timid/choosy top predator that preferred the pest to the mesopredator was more effective when the ratio was low. Our results show that the behavioral types and abundances of interacting species need to be considered together when studying food-web dynamics, because they evidently interact. To improve biocontrol efficiency of predators, research on the alteration of their behavioral types is needed.

顶级捕食者（top predator）个体间的行为变异（behavioral type）可显著调控集团内捕食（intraguild predation, IGP）系统中的害虫抑制效应。然而，顶级捕食者的行为型——具体涵盖觅食攻击性（foraging aggressiveness，致死猎物数与捕食耗时的比值）与猎物选择性（prey choosiness，对特定猎物类群的偏好程度）——对IGP动态的影响，可能会与顶级捕食者、中级捕食者（mesopredator）及害虫的相对丰度产生交互作用。本研究借助模拟模型（simulation model），针对由顶级捕食性蜘蛛、中级捕食性蜘蛛与木虱（psyllid）害虫组成的三物种种群系统，探究了顶级捕食者行为型对IGP动态的影响；模型参数均通过实验室实验与野外观测数据估算得到。研究结果显示，顶级捕食者的行为型会以环境依赖的方式改变食物网动态：当顶级捕食者与中级捕食者的丰度比值较高时，具备攻击性且无猎物偏好（即对害虫与中级捕食者无区分偏好）的顶级捕食者所在系统，可实现更显著的害虫抑制效果；与之相反，当该丰度比值较低时，偏好害虫而非中级捕食者的胆怯且具有选择性的顶级捕食者系统，其害虫防治效果更佳。本研究结果表明，在探究食物网动态时，需同时考虑交互物种的行为型与丰度，二者间存在显著的交互效应。若要提升捕食者的生物防治（biocontrol）效率，需针对其行为型的调控开展相关研究。