PIGEON HOMING - THE INFLUENCE OF TOPOGRAPHICAL FEATURES IN SUCCESSIVERELEASES AT THE SAME SITE

A new device, the direction-recorder, offered the possibility to exten d earlier studies of homing behaviour of pigeons when relevant topogra phical elements (mountains and large tracts of water) interpose betwee n the release site and the home loft. Three series of experiments were carried out at three different sites to investigate intraindividual a nd intraindividual variability in subsequent tosses from the same loca lity. Two release sites were chosen behind a mountain chain with respe ct to home; at the third site homeward directed route crosses the sea. From our results it turns out that homing pigeons may adopt different strategies. Moreover, a wide intraindividual variability was observed in repeated tosses at the same site; some pigeons remained faithful t o the first route, whereas other birds tried successive new routes whi ch, in most cases, were significantly shorter than previous ones. This result indicates that pigeons try, and are actually able, to improve their performance in subsequent releases from the same site. (C) 1997 Elsevier Science B.V.