Avoidance conditioning of jackdaws ( Corvus monedula) to distress calls

Abstract

Jackdaws were conditioned to avoid or escape broadcast jackdaw distress calls. The calls were preceded by 10 s of stimulus light which accompanied the broadcast calls for 4 min. Following this, there was a 2-min time-out period without light or sound, after which the stimulus light was illuminated once again. A response (key peck) during the light or light plus sound periods terminated these. Extinction was accomplished with the stimulus light only. Median latencies of response were compared when calls were broadcast using high and low fidelity equipment. Median latencies to the HF calls were significantly shorter than those to LF calls. A comparison was also made between HF calls and discrete 1 kHz tone segments. The median latencies for the tone segments were longer than those for HF calls. HF jackdaw calls were compared with high pass calls (containing only frequencies above 5 kHz) and with HF herring gull distress calls. In both cases, the median response latencies were similar to those for HF jackdaw calls.