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[When animals encounter a novel environment they can either reject it and leave or accept it and explore their new home. It is important to understand what governs animals' response to a novel place because of the fitness consequences and wildlife management implications entailed. Here I examine the spatial behaviour of translocated African elephants (Loxodonta africana) upon arrival at a novel environment. I monitored the movement patterns of 12 radio-collared elephants for a year post-translocation. I documented the first account of both female and male African elephants homing back to their natal habitat. More males than expected left the release site, but female–calf units also homed to their natal habitat, demonstrating that homing is not confined to one sex or age. When examining the spatial behaviour of elephants that remained near the release site I did not find a relationship between habitat exploration and last distance from release site, elephant age, or social association. However, I did find a negative correlation between habitat exploration and distance from human activities. This work provides biological insights regarding individual variation in spatial activity of animals in a novel environment and offers recommendations for future management actions., When animals encounter a novel environment they can either reject it and leave or accept it and explore their new home. It is important to understand what governs animals' response to a novel place because of the fitness consequences and wildlife management implications entailed. Here I examine the spatial behaviour of translocated African elephants (Loxodonta africana) upon arrival at a novel environment. I monitored the movement patterns of 12 radio-collared elephants for a year post-translocation. I documented the first account of both female and male African elephants homing back to their natal habitat. More males than expected left the release site, but female–calf units also homed to their natal habitat, demonstrating that homing is not confined to one sex or age. When examining the spatial behaviour of elephants that remained near the release site I did not find a relationship between habitat exploration and last distance from release site, elephant age, or social association. However, I did find a negative correlation between habitat exploration and distance from human activities. This work provides biological insights regarding individual variation in spatial activity of animals in a novel environment and offers recommendations for future management actions.]

Pigeons exposed to a random oscillating magnetic field prior to release from Bolgheri, 50 km SSE from their loft (near Pisa) were observed to behave in a consistent manner. Generally, the birds initially flew westwards, and all approached the sea with or without detours. Two interesting cases were pigeons 5 and 18 (see Fig. 1 ) which optically vanished east from the release site but none the less arrived at the coast. Subsequently, the pigeons were found to shift their orientation to the NNW, the homeward direction. Flight periods were regularly interrupted by pauses, but pigeons were not observed to correct their initial aberrant orientation after pauses. An actual flight of 5 to 10 minutes was necessary before they shifted their orientation homeward. Shift occurrence was found to be more related to distance reached from the release site than flight duration per se. We believe that a flight of a few km may have been sufficient to allow the pigeons to extract some needed piece of environmental information which then allowed them to locate the home direction.

Given that past experiments produced different results when similar homing experiments were performed with Cornell (Ithaca NY, U.S.A.) and Pisa (Italy) pigeons, an additional series of new tests were performed using Cornell pigeons. Two pre-experimental treatments were used. One group of pigeons was maintained according to standard procedures for Cornell pigeons, the other group in a manner typical of Pisa pigeons, the main difference between the two groups was that the former were trained up to 25 km from the loft, whereas the latter were untrained but were free to fly around the loft area 2 to 6 days per week. Two series of four experimental releases were conducted at 31-34 and 57-67 km by releasing unmanipulated controls (both trained and untrained pigeons not rendered anosmic) and experimentals (both trained and untrained pigeons rendered temporarily anosmic during transport and also at the release site). When the pooled data on initial orientation are considered, the control groups show a small but significant homeward directedness, whereas the orientation of the anosmic birds is not different from random. The homing performance of anosmic birds was also significantly reduced. Thus, the results show that Cornell pigeons use olfactory cues for navigation. A residual homeward tendency found in the initial orientation of anosmic birds, though not significant, suggests the existance of an auxiliary non-olfactory mechanism whose nature is unknown, and which calls for further investigations. Both controls and experimental pigeons that had pre-test training were better orientated and homed better than their untrained counterparts. The trained groups also exhibited directional tendencies that were different from those of the untrained pigeons.

In addition to their well described map and compass mechanisms, homing pigeons can also rely on information gathered during previous visits to a release site (familiar-site information) to orient home from that location. In the present study, we wished to clarify the nature of the spatial information acquired during visits to a release site. Clock-shifted homing pigeons, rendered anosmic such that they could only rely on familiar-site information to orient homeward, failed to display the typical shift in initial orientation indicative of sun compass use as displayed by controls. This result indicates that familiar-site information can be used not only for recognition of previous visited locations, but also to guide a pigeon's orientation response. However, there was an increase in scatter in the vanishing bearings of clock-shifted pigeons whose initial orientation was based on familiar-site information, suggesting that the solar cues were part of the available familiar-site information. Finally, clock-shifted pigeons who could rely on both their navigational map and familiar-site information for initial orientation behaved in a manner suggesting primary use of their navigational map with additional reference, at least to a limited degree, to familiar-site information.