Relationships Between Social Structure and Response To Novelty in Captive Jackdaws, Corvus Monedula L., I. Response To Novel Space

The response of six groups of captive, handreared jackdaws, Corvus monedula L. (Aves), to a novel space was tested. Birds were tested in groups and were free to make contact with the novelty or remain in a familiar area. The individual manner of response was related to the social position of the individual. i) Exploratory behaviour occurred in bouts. Familiarization with the novelty was mostly gradual, but in some groups after an initial delay, the entire group began to explore and then to enter the novel space very rapidly ("avalanche"). ii) In each group one or two birds performed most of the early exploration, and termed "initiators". iii) The initiator in each group was distinguished from all others by duration and by frequency measures. Both for approach and for entering of the novel space (a) birds that scored high on the frequency measure, scored high also on the duration measure, (b) birds that scored high on either measure, for the approach, were the most likely to score high on that measure for the entering. iv) In all six groups the "initiators" were sociall mid or low ranking birds. v) Top ranking birds were distinguished from all others by the combination of two features; (a) they did not act as initiators, and (b) they were not the last to peak in their duration inside the novel space. It is argued that top ranking birds are more conservative, and that it benefits them as they have relatively more to lose and less to gain by being exploratory. The converse is true for mid or low ranking birds, which may benefit by exploiting resources outside the reach of the high ranking birds.