The effect of predator presence on the behavioral sequence from host selection to reproduction in an invulnerable stage of insect prey

Abstract

Predator-prey interactions primarily focus on prey life-stages that are consumed. However, animals in less vulnerable life-stages might also be influenced by the presence of a predator, making our understanding of predation-related impacts across all life-stages of prey essential. It has been previously demonstrated that Podisus maculiventris is a voracious predator of eggs and larvae of Leptinotarsa decemlineata, and that larvae will alter their behavior to avoid predation. However, the adult beetles are not readily consumed by P. maculiventris, raising the question of whether they will respond to predators to protect themselves or their offspring. Here, we examine the effect of predation risk by P. maculiventris, on three adult behaviors of L. decemlineata; colonization, oviposition, and feeding, and the resulting impact on host plant damage. In an open-field test, there was no difference in natural beetle colonization between plots with predation risk and control treatments. However, subsequent host plant damage by adult beetles was 63.9% less in predation risk treatments. Over the lifetime of adult beetles in field mesocosms, per capita feeding was 23% less in the predation risk treatment. Beetle oviposition was 37% less in the presence of predators in a short-term, greenhouse assay, and marginally reduced in longer term field mesocosms. Our results indicate that predation risk can drive relatively invulnerable adult herbivores to adjust behaviors that affect themselves (feeding) and their offspring (oviposition). Thus, the full impact of predator presence must be considered across the prey life cycle.

Plant genotypic diversity interacts with predation risk to influence an insect herbivore across its ontogeny

“…CPB surprisingly did not reduce oviposition in patches with predation risk in the adult behavior experiment even though other studies, which looked at responses of CPB to larger aggregations of stink bugs, have shown that adults are capable of responding to cues from stink bugs (Herman and Thaler ). One hypothesis for this result is that adults perceive leaving a patch as costly in terms of reduced feeding time, and they may value their own feeding over safety for their larvae.…”

Chemical cues linked to risk: Cues from below‐ground natural enemies enhance plant defences and influence herbivore behaviour and performance

“…We interpreted this finding as evidence that they perceive EPN cues as a warning of a threat to the performance or survival of their offspring. Female insects often use chemical information to select suitable oviposition sites, often to avoid plant defence, competition or elevated predation risk (Hermann & Thaler, ; Kariyat et al, ; De Moraes et al, ). During the CPB oviposition experiment, one plant in each arena was exposed to EPN‐infected cadavers for 3 days.…”

“…The roles of semiochemicals from plants and herbivores, particularly in above‐ground systems, have been fairly well characterized, whereas below‐ground chemical cues and cues from natural enemies have received less attention. The ecological importance of these cues, however, is increasingly recognized, as evidenced in recent empirical work (Hermann & Thaler, ; Rasmann, Hiltpold, & Ali, ; Seo, Rivera, Stelinski, & Martini, ; Willett, Alborn, Duncan, & Stelinski, ). Chemical cues from natural enemies can warn prey organisms about their risk of attack, and we predict they could also provide information to plants about the presence of beneficial organisms that aid in plant defence.…”

Bugs scaring bugs: enemy‐risk effects in biological control systems

“…Behavioural shifts are a commonly studied trait responses in arthropods, and are generally the most rapid and reversible. Examples include changes in time spent feeding (Thaler and Griffin, 2008;Jandricic et al, 2016;Ingerslew and Finke, 2017), food source (Schmitz et al, 1997), microhabitat and refuge use (Lucas et al, 2000;Lawson-Balagbo et al, 2007;Penfold et al, 2017), oviposition rate (Deas and Hunter, 2013;Hermann and Thaler, 2018), oviposition site selection (Angelon and Petranka, 2002;Vonesh and Blaustein, 2010;Silberbush and Blaustein, 2011), short-distance escape (Tamaki et al, 1970;Nelson, 2007;Fill et al, 2012) and dispersal (H€ oller et al, 1994;Henry et al, 2010;Welch and Harwood, 2014;Otsuki and Yano, 2014b).…”