HELICOPTER OBSERVATIONS OF HOMING IN PIGEONS WITH BIASED ORIENTATION BECAUSE OF DEFLECTED WINDS AT THE HOME LOFT

SUMMARY Thirteen flocks of homing pigeons have been followed by helicopter; the birds had been kept since they were fledglings, or at least for several months, in cages equipped with screens, which produced a deflection of the wind blowing through the cages. Releases have been performed from different directions and distances, up to 67 km. Our observations confirm the tendency of the birds to deflect from the home direction in the same ways as the wind was deflected in the cages; this tendency is displayed not only at departure, but can last for much of the flight. The courses were variable and apparently affected by landscape features. The route corrections were mostly abrupt; they also seem to be affected by topographical factors.