Pigeon navigation: Effects upon homing behaviour by reversing wind direction at the loft

Summary In order to test the nature of the information acquired by pigeons at home and utilized as map component in their navigational mechanism, groups of birds were kept since fledging time in glass corridors, which had their main axis oriented E-W (or ESE-WNW). Referring to the quadrants centered by these directions as experimental quadrants, the treatment of the birds was as follows. Whenever a wind was blowing from one of the experimental quadrants, C1-and C-birds were subjected to an artificial air current blowing from the center of the same quadrant, and E-birds to air currents from the center of the opposite quadrant. C2-birds, reared in a corridor which was unscreened at both ends, were not treated with artificial winds and could perceive the natural winds from the experimental quadrants. Finally, S-birds were never exposed to either natural or artificial winds.When released from directions comprised in the xperimental quadrants, C-, C1-, and C2-birds were homeward oriented, while E-birds oriented themselves toward the opposite direction (Fig. 7), and S-birds' bearings were random. The homing performances of E-birds were poorer than those of the other birds, and on some releases, disastrous.It is concluded that the information that pigeons acquire at home and then use for navigational purposes is wind borne and can be conveyed by an artificial air current. This confirms previous results which indicated the olfactory nature of the information.Dedicated to Prof. Dr. H. Autrum, on occasion of his seventieth birthdayThis study was supported by the Cosiglio Nazionale delle Ricerche. We thank the Command of the Brigata Paracadutisti Folgore, Italian Army, which kindly allowed us to use a power boat for the releases from over the sea. We also wish to thank Dr. R.F. Hartwick for valuable help with some experiments and for stimulating discussions, Mr G. Mela and Mr D. Moretti for constructing the control drices for the fans.