Short distance phase shifts revisited: tracking clock-shifted homing pigeons (Rock Dove Columbia livia) close to the loft

Clock-shifted pigeons (Rock Dove Columba livia) were tracked from familiar release sites using a direction recorder. At a relatively short distances from the home loft (< 3.2 km), it was discovered that two different mechanism for homing were present. One involved the sun compass and the other was independent of this. At a further site (9.95 km) none of the birds used the sun compass for navigation. The possibilities for the non-sun compass-based mechanism are discussed.