The responses of Central European avian predators to an allopatric aposematic true bug

Abstract

A mimicry ring of red-and-black pentatomorph true bugs in Central Europe had been proposed to occur based on avoidance of its mutually non-relative members, which was confirmed based on responses of avian predators. We compared the responses of two species of European insectivorous passerines (great tit Parus major, blue tit Cyanistes caeruleus) to a typical member of the proposed ring (red firebug Pyrrhocoris apterus) and to a similarly coloured south Asian species of true bugs (red cotton bug Dysdercus cingulatus) to test if the allopatric species will be included in the proposed ring. Additionally, individuals of both bug species with colour signals artificially removed were offered to birds to assess the effect of chemical protection per se. Birds attacked the unmodified red cotton bugs more often than the red firebugs, which suggests that the birds did not include the red cotton bug in the proposed mimetic ring. Red cotton bugs were eaten by a greater number of birds than were the brown-painted red firebugs at first encounter. However, the birds quickly learned to avoid all visually unprotected bugs, suggesting that the red cotton bug possesses an effective chemical protection.