Figure 1.

The wren response to broadcasts of song from a control and three cuckoo species. The results are shown as mean ± se for the following response variables: (a) the number of wren alarm calls, (b) the minimum distance (m) to approach the playback speaker, and (c) the latency (s) to respond within 10 m of the playback speaker. The song stimuli that were broadcast in the wren territories were from the following species: control = familiar non-parasite (striated thornbill), low risk = little bronze-cuckoo, moderate risk = shining bronze-cuckoo, and high risk = Horsfield’s bronze-cuckoo. We compared wren response during the peak breeding period (N = 90 playback experiments) and the opportunistic breeding period (N = 83 playback experiments). The study was done on Kangaroo Island in South Australia.