Surface texture and priming play important roles in predator recognition by the red-backed shrike in field experiments.

Abstract

We compared the responses of the nesting red-backed shrikes (Lanius collurio) to three dummies of a common nest predator, the Eurasian jay (Garrulus glandarius), each made from a different material (stuffed, plush, and silicone). The shrikes performed defensive behaviour including attacks on all three dummies. Nevertheless, the number of attacks significantly decreased from the stuffed dummy through the plush dummy and finally to the silicone dummy. Our results show that wild birds use not only colours but also other surface features as important cues for recognition and categorization of other bird species. Moreover, the silicone dummy was attacked only when presented after the stuffed or plush dummy. Thus, we concluded that the shrikes recognized the jay only the stuffed (with feathered surface) and plush (with hairy surface) dummies during the first encounter. Recognition of the silicon dummy (with glossy surface) was facilitated by previous encounters with the more accurate model. This process resembles the effect of perceptual priming, which is widely described in the literature on humans.