Predator cues have contrasting effects on lifespan ofPardosa milvina(Araneae: Lycosidae)

Abstract

Predators can affect prey indirectly by eliciting changes in behavior, morphology, and life history. These nonconsumptive effects are often mediated by predator cues used by prey to avoid capture. However, predator cues can cause stress responses in prey that negatively impact survival and reproduction. We explored responses of the wolf spider Pardosa milvina (Hentz 1844) to cues from the larger wolf spider Tigrosa helluo (Walckenaer 1837) and the ground beetle Scarites quadriceps Chaudoir 1843. We exposed Pardosa to cues from both predators and measured changes in body size, weight, consumption, and lifespan. We found significant effects of predator cues only on female longevity: females exposed to Tigrosa cues had shorter lifespans than those exposed to cues from Scarites. The lack of treatment effects on energy intake suggests that predator cues act through physiological pathways. Future experiments may uncover opposing hormonal mechanisms underlying the observed differences in lifespan.

Tri‐partite complexity: odour from a psyllid's mutualist ant increased predation by a predatory mite on the psyllid

“…In a previous study significant reduction in the longevity of prey was sexually dimorphic when exposed to cues from the predaor . When the spider Pardosa milvina (Hentz 1844) was exposed to predators cues from the larger wolf spider Tigrosa helluo (Walckenaer 1837), P. milvina females had significantly shorter lifespans than those spiders without predator cues . However, in our study a sexually dimorphic response was only observed in the longevity of male A. limonicus exposed to ant odour, despite a lack of impact on the development and survival rates.…”

“…In a previous study significant reduction in the longevity of prey was sexually dimorphic when exposed to cues from the predaor . When the spider Pardosa milvina (Hentz 1844) was exposed to predators cues from the larger wolf spider Tigrosa helluo (Walckenaer 1837), P. milvina females had significantly shorter lifespans than those spiders without predator cues .…”

“…Although previous studies show that predator cues can decrease or increase prey development and growth rate, we did not find such evidence in our research. Ant odour did not reduce the consumption rates of A. limonicus males, which meant that energy intake by males was not likely to be the cause for the reduction in longevity . The precise mechanism of sexual dimorphism underlying differences in longevity through exposure to predator cues is still unknown.…”

Scaling up our understanding of non-consumptive effects in insect systems

“…Shifts in insect prey traits in response to predators include behavioral changes [7][8][9][10][11], life history adjustments [12][13][14], and physiological changes [15][16][17][18][19] (See Table 1 & 2 for behavioral and physiological changes, respectively). The majority of studies to date link NCEs to changes in behavior, including changes in feeding [20][21][22], oviposition [23,24], colonization or dispersal [25][26][27], host-plant preference or habitat use [28][29][30] and increased predator avoidance [31,32].…”

Contrasting patterns of ground spider and beetle activity across a Japanese knotweed-dominated riparian gradient

“…Decreases in litter complexity may also be associated with increases in cannibalism and/or intraguild predation due to both a lack of refugia and a loss of alternative prey (Wagner and Wise, 1996) but reduced prey also can increase exploitative competition among ground spiders (Wise and Wagner, 1991). At least within agricultural systems, there is evidence that ground beetles and ground spiders can have nonconsumptive effects on lifespan and behavior mediated by cues from intraguild predators (Sitvarin 2014;Sitvarin, Breen, and Rypstra 2015;Sitvarin et al 2016;Sitvarin and Rysptra 2014).…”