Predator dependent mimetic complexes: Do passerine birds avoid Central European red-and-black Heteroptera?

Abstract

Abstract. True bugs are generally considered to be well protected against bird predation. Sympatric species that have similar warning coloration are supposed to form a functional Müllerian mimetic complex avoided by visually oriented avian predators. We have tested whether these assumptions hold true for four species of European red-and-black heteropterans, viz. Pyrrhocoris apterus, Lygaeus equestris, Spilostethus saxatilis, and Graphosoma lineatum. We found that individual species of passerine birds differ in their responses towards particular bug species. Great tits (Parus major) avoided all of them on sight, robins (Erithacus rubecula) and yellowhammers (Emberiza citrinella) discriminated among them and attacked bugs of some species with higher probability than others, and blackbirds (Turdus merula) frequently attacked bugs of all the tested species. Different predators thus perceive aposematic prey differently, and the extent of Batesian-Müllerian mimetic complexes and relations among the species involved is predator dependent.

The Role of Life-History and Ecology in the Evolution of Color Patterns in Australian Chrysomeline Beetles

“…Indeed, avian species richness is correlated with vegetation structure complexity and species (Shurcliff, 1980;Nally et al, 2008;Brady and Noske, 2010), and with rainfall (Tischler et al, 2013), and the greater the ratio of Eucalypts to Acacia, the higher the avian species richness (Brady and Noske, 2010). However, as avian species and individuals may differ in their reactions to aposematic prey (Exnerová et al, 2008;Svádová et al, 2010), there may be varying selection pressures on leaf beetle color pattern. Together, the background and the predator community can affect the direction and strength of selection for warning coloration (Prudic et al, 2007a;Lindstedt et al, 2011).…”

Gregariousness as a defence strategy of moderately defended prey: experiments with Pyrrhocoris apterus and avian predators

“…Individuals of all four species studied (Lygaeus equestris, Spilostethus saxatilis, Graphosoma lineatum and Pyrrhocoris apterus) are avoided to the same extent by wild-caught great tits (Parus major), which suggests that their relationships are Müllerian (Hotová Svádová et al, 2010). However, experiments with naive juvenile great tits have shown that P. apterus is less defended than the other three species, and that its relationships to them are likely to be quasi-Batesian (Hotová Svádová et al, 2013).…”

“…In our studies of mimetic complex of European red-and-black true bugs (Heteroptera), we came across a seemingly paradoxical situation (Hotová Svádová et al, 2010. Individuals of all four species studied (Lygaeus equestris, Spilostethus saxatilis, Graphosoma lineatum and Pyrrhocoris apterus) are avoided to the same extent by wild-caught great tits (Parus major), which suggests that their relationships are Müllerian (Hotová Svádová et al, 2010).…”

“…In this particular case, and possibly also in other cases of unequally defended co-mimics, gregariousness of weakly defended mimic promotes mutualistic relationships (rather Müllerian than quasi-Batesian) between the mimetic species. Experience with gregarious firebugs can also explain why the wild-caught great tits behaved differently than the hand-reared ones towards the mimetic complex of red-and-black European true bugs (Hotová Svádová et al, 2010.…”

Reactions of green lizards (Lacerta viridis) to major repellent compounds secreted by Graphosoma lineatum (Heteroptera: Pentatomidae)

“…The firebug (Pyrrhocoris apterus, Heteroptera: Pyrrhocoridae) was chosen as a second model organism to test the lizards' reactions to another living specimen of aposematic red-and-black Heteroptera (Hotová Svádová et al, 2010), which lives in the same habitat as the captured green lizards (Podyjí National Park). The firebugs were kept in captivity under simulated natural conditions, similarly to the striated shieldbug.…”