Prey state alters trait-mediated indirect interactions in rocky tide pools

Several studies on trait-mediated indirect interactions (TMIIs) have shown that predators can initiate trophic cascades by altering prey behaviour. Although it is well recognized that individual prey state alters antipredator and foraging behaviour, few studies explore whether this state-dependent prey behaviour can alter the strength of the ensuing tritrophic cascade. Here, we link state-dependent individual behaviour to community processes by experimentally testing whether hunger level and body size of prey altered antipredator behaviour and thus changed the strength of trophic cascades between predators and primary producers. In rocky intertidal tide pools on the California Coast, waterborne cues from the predatory seastar Leptasterias spp. (Stimpson) can cause the herbivorous snail Tegula (Chlorostoma) funebralis (A. Adams) to reduce grazing and flee tide pools, resulting in positive indirect effects on tide pool microalgae. However, we show that the strength of this behaviourally...多项针对性状介导的间接相互作用（trait-mediated indirect interactions, TMIIs）的研究表明，捕食者可通过改变猎物行为触发营养级联。尽管学界已充分认识到猎物个体状态会改变其反捕食与觅食行为，但鲜有研究探讨这种依赖于状态的猎物行为是否会改变后续三营养级级联的强度。本研究通过实验检验猎物的饥饿水平与体型是否会改变其反捕食行为，进而改变捕食者与初级生产者之间的营养级联强度，将依赖于状态的个体行为与群落过程关联起来。 在加利福尼亚海岸的岩相潮间带潮池中，捕食性海星Leptasterias spp.（Stimpson）释放的水传信号可促使草食性螺类Tegula（Chlorostoma）funebralis（A. Adams）减少啃食并逃离潮池，从而对潮池微藻产生正向间接效应。 然而本研究表明，此种行为介导的……的强度