Ambulatory responses of Laricobius nigrinus (Coleoptera: Derodontidae), a hemlock woolly adelgid predator, to odors from prey, host foliage, and feeding conspecifics.
Behavioral interactions between insects and their environments are often mediated by volatile cues. Plant-produced chemical cues induced by herbivore activity are often more effective at attracting predators than are cues produced by the herbivore alone (Dicke and van Loon 2000). The presence of herbivore-induced plant volatiles makes foraging by predators more efficient than undirected hunting (Dannon et al. 2010), presumably because they indicate the presence of prey. Just as it is common for predators to find prey using olfactory cues, they can also use chemical cues to avoid intraguild competition or aggression (Janssen et al. 1995; Cakmak et al. 2006, Flowers et al. 2007), and evidence suggests that avoidance is a common response to the reception of a conspecific cue from a particular location (Janssen et al. 1995; Stout and Goulson 2001; Gnanvossou et al. 2003). Understanding these interactions may be important to the implementation of a biological control program in which a natural enemy complex is released and established, because they are integral to how predators find their hosts (Flowers et al. 2007). Information about predator interactions can inform the optimal release density of agents on the landscape and increase the efficiency and effectiveness of programs.