![]() ![]() ![]() Furthermore, prey and omnivores may counter-attack the predators or even feed on them (Aoki et al. In this case, the interaction between the two prey species can be classified as intraguild predation, but the omnivore and predators are also involved in intraguild predation. feeds on the other prey species and on the shared host plant. Interactions become even more complicated when one of the two prey species is an omnivore, i.e. Predators may avoid such patches because they have to compete for the shared prey with the intraguild prey. ![]() For instance, one prey species (the so-called intraguild prey) may attack and feed on the other prey species (the so-called shared prey), whereas both are attacked by the predator (the intraguild predator, Holt and Polis 1997). 2003).Īnother level of complexity is added to predator patch selection when the prey species involved do not have the same ecological role. 2005 Chung and Felton 2011), and these defences, in turn, may affect the quality of the herbivores as food for the predators (Havill and Raffa 2000 Harvey et al. For example, populations of two herbivore species that feed on the same plant can affect each other through the induction of plant defences (Agrawal 2000 Viswanathan et al. Also, when different prey species co-occur on the same patch, the interactions between these prey can affect patch quality and patch selection for predators (Werner and Peacor 2003 Ohgushi 2005 Schmitz et al. 2001) and of intraguild predators (Moran and Hurd 1994 Magalhães et al. 2015) and the avoidance of competing species (Janssen et al. Since then, it has become clear that many more factors are involved in patch selection by predators, such as the need for a mixed diet (Belovsky 1978 Mayntz et al. ![]() 1992), sometimes combined with the risk of predators becoming prey themselves (Sih 1980 Caraco et al. Our results point at the importance of predatory interactions among prey species for patch selection by predators.Įarly theory on prey patch selection assumed that predators select patches based on the rate of food intake (Charnov 1976 Stephens and Krebs 1986 Kacelnik et al. This explains the reduced attractiveness of patches with both prey. We also investigated the cues involved in patch selection and found that the attractiveness of patches with spider mites was significantly reduced by the presence of cues associated with killed spider mite eggs. Patches with thrips only were not significantly more attractive than empty patches. Patch selection and oviposition preference of predators matched performance: predators preferred patches with spider mites over patches with spider mites plus thrips. We found that performance of the predatory mite was highest on patches with spider mites, intermediate on patches with spider mites plus thrips larvae and lowest on patches with thrips larvae alone. A further complicating factor is that the thrips can also feed on the eggs of the predator. The two prey species co-occur on several plant species, on which they compete for resources, and western flower thrips feed on eggs of the spider mites. The predatory mite Neoseiulus californicus preys on young larvae of the western flower thrips Frankliniella occidentalis and on all stages of the two-spotted spider mite Tetranychus urticae. The effect of one such interaction, intraguild predation between prey, on patch selection by predators was studied here. However, interactions between the prey species may also affect prey choice, and this has received limited attention. When predators can use several prey species as food sources, they are known to select prey according to foraging efficiency and food quality. ![]()
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