Prey life stages modulate effects of predation stress on prey lifespan, development, and reproduction in mites

The non-consumptive effects of predator-induced stress can influence a variety of life-history traits. Many previous studies focused only on short-term effects such as development and reproductive rates. Recent studies have showed that long-term predation stress (given during the whole life of the prey) and short-term predation stress (provided during the immature stage of the prey) could generate completely opposite results: the former could decrease lifespan, whereas the later could increase lifespan. However, it is still unclear whether the advantage is because of the short duration of exposure or the early stage of life during which exposure was exerted. Thus, in this study, the prey (Tyrophagus putrescentiae) was exposed to predation stress from the predator (Neoseiulus cucumeris) during different life stages (larva, protonymph, tritonymph, first 5 d of oviposition, the full lifespan or none of the above). The results showed that the predation stress supplied during larval and protonymphal stage delayed development, reduced fecundity and prolonged lifespan of the prey, while the stress given during tritonymphal stage only reduced lifespan slightly and the stress given during the first 5 d of oviposition did not change lifespan but reduced fecundity. This study indicated that the effects of predation stress are dependent on prey life stage and the predation stress experienced in the early life stages is important to lifespan modulation.