Pigeon homing: Different effects of olfactory deprivation in different countries

Abstract

This study compares the orientation of untreated pigeons and pigeons subjected to olfactory deprivation at two lofts near Pisa, Italy, at a loft at Ithaca, New York, USA, and at a loft at Frankfurt a.M., FRG. The experimental birds were rendered anosmic by nasal plugs until Gingicain, a local anaesthetic, was applied shortly before release. The Italian and American control pigeons appeared to orient towards home equally well, while the control pigeons in Germany frequently preferred directions that deviated significantly from the home direction. The effect of olfactory deprivation was small in the USA and in Germany; it was significantly larger in Italy, indicating that Italian pigeons depend on olfactory information to a much greater extent. These findings suggest that there are important regional differences in the strategies and cues pigeons use to navigate. The varied roles of olfactory information, and the reasons for these differences are discussed.