Initial orientation and homing behaviour of pigeons under the influence ofshort wave transmissions

I. Steiner et B. Bruderer, Initial orientation and homing behaviour of pigeons under the influence ofshort wave transmissions, J ORNITHOL, 140(2), 1999, pp. 165-177
Citations number
Categorie Soggetti
Animal Sciences
Journal title
ISSN journal
0021-8375 → ACNP
Year of publication
165 - 177
SICI code
In order to test the potential influence of short wave radiation on the hom ing behaviour of pigeons we positioned two lofts with adult homing pigeons in the vicinity of a short wave transmitter. One loft was next to the trans mitter and fully exposed to the radiation, the second protected against the radiation (a) by topographical features and (b) by its position in a secto r that was not used for transmission during daytime. In both lofts young pi geons were raised and used for experimental flights at the age of three mon ths. Adults accustomed to the new sites as well as young birds from the exp osed and non-exposed lofts, respectively, were released some 11 km from the loft for homeward flights towards the transmitter, with and without transm ission towards the relevant sector. Vanishing direction and vanishing time were not affected by the short wave radiation in any of the groups, thus corroborating earlier experiments with pigeons flying homewards from the transmitter towards distant lofts. Howev er, all three groups raised in the absence of short wave radiation (A-, A+, J-) homed tendentially faster in situations where radiation was absent com pared to situations with radiation. Pooled in one data set the three groups were significantly faster without radiation. On the other hand, the two ju venile groups raised under radiation (J1+ and J2+) homed at the same speed under both short wave situations. Furthermore, all five groups tended to ch oose lower flight altitudes when released under the influence of short wave radiation (significantly when groups were pooled). Besides the experiments , observations near the loft gave the impression that the pigeons kept in t he exposed loft were reluctant to fly in the neighbourhood of the loft, par ticularly the adults. We conclude that short wave radiation can be felt by the pigeons, but does not interfere with their initial orientation. Reduced homing speeds of bird s grown up without experiencing radiation, low flight levels in flights und er radiation in all groups, and a general reluctance to fly of the pigeons next to the exposed loft, suggest that the radiation has an undefined negat ive effect on the birds. Unimpaired homing speeds in juveniles having grown up under varying field strengths suggest that homing pigeons can become ac customed to short wave radiation to a certain extent.