Predator experience changes spider mites’ habitat choice even without current threat

Abstract

As recent studies have revealed, previous exposure to a predator can change prey behavior even in the absence of current threat. We hypothesized that experiencing a predator increases prey avoidance of lower-quality resources even in the absence of a predator, which in turn influences the prey’s spatial distribution. We examined these hypotheses using the herbivorous spider mite Tetranychus kanzawai and the specialist predatory mite Neoseiulus womersleyi. We used Phaseolus vulgaris as a high-quality host plant and Hydrangea macrophylla as a low-quality host plant. First we examined whether T. kanzawai females that were previously exposed to predators preferred P. vulgaris to H. macrophylla under no current threat more than those without predator experience. Second, we tested the effect of predator experience on dispersal by T. kanzawai females on P. vulgaris or on H. macrophylla. Our results show that: (1) predator-experienced T. kanzawai females expressed stronger avoidance of the low-quality plant H. macrophylla than those without predator experiences; and (2) T. kanzawai females transferred to H. macrophylla traveled farther than those on P. vulgaris, especially females with previous predator experience. These findings reveal neglected aspects of the evolutionary interaction between predators and the habitat choices of their prey.

Propagule pressure rather than population growth determines colonisation ability: a case study using two phytophagous mite species differing in their invasive potential

“…For example, they may rely on chemical cues (kairomones) secreted by adjacent plants, informing about the quality of nearby hosts or about the presence of competitors or predators. Such informed dispersal has been shown in many animal species (Sabelis & Afman, 1994;Jung & Croft, 2001;Bowler & Benton, 2005;Clobert et al, 2009), including spider mites and predatory phytoseiid mites (Janssen et al, 1997;Bitume et al, 2013;Murase & Fujita, 2018;Van Petegem et al, 2018); however, although this has been experimentally tested in eriophyid mites, it has not been confirmed (Melo et al, 2014). Active dispersal can also contribute to the range increase via slow diffusive spread once organisms have been introduced to a new area (Gozlan et al, 2010), albeit on a smaller spatial scale than passive dispersal.…”

Two New Records for Spider Mite Fauna of Turkey, Tetranychus kanzawai Kishida and Eotetranychus rubiphilus Reck (Trombidiformes: Tetranychidae)

“…However, T. urticae in Japan is observed only in agroecosystems where predators are less abundant, whereas T. kanzawai lives on wild plants where predators are abundant. Because, it is known that T. kanzawai potentially encounters predators more frequently than T. urticae does (Murase et al, 2018).…”

“…Neoseiulus fallacis (Garman) (Mesostigmata; Phytoseiidae) is effective on tea (Zhang 2003). It is also associated with Neoseiulus longispinosus (Evans) (Zhang 2003) and Neoseiulus womersleyi (Schicha) (Mesostigmata; Phytoseiidae) (Murase and Fujita 2018). Besides predator mites, T. kanzawai can also be controlled by predatory insects.…”