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The golden hamster carries food back to its nest along a direct path. In a situation combining a passive outward journey with the elimination of visual and various other exteroceptive cues, the subjects continued to return to their nest site and were not influenced by alterations of the earth's magnetic field. Experiments in which the animals started their hoarding trips from a changing point of departure, or were transferred to an unfamiliar experimental space, suggest that they orientate by path integration and that they assess the angular, but not the linear component of a passive outward journey.

When hoarding food in an experimental arena (o = 2.20 m), golden hamsters tend to return along a direct path from the food source at the centre of the arena to their peripherally located nest. Under infra-red light the animals' homing behaviour is exclusively controlled by 'internal' cues which have been generated during the outward journey to the feeding place. The paper examines the limitations on the registration and computation of directional cues which originate from an active or a passive outgoing trip. The compensation of the angular component of the outward journey was examined by inducing the subjects to walk (actively) around the centre of the arena, or by rotating the animals (passively) on a platform which contained the food source. The greater the number of rotations, the less precise the homing performance. After three to five active rotations, and after two to three passive rotations of 360°, the animals ceased to yield significant homing vectors. Unidirectional rotations induced a systematic ipsidirectional bias, an indication of undercornpensation; no bias was observed after rotations which occurred in equal extents in both directions. Special importance was given to the compensation for passive translations. The experiments involved either the shift of the subjects from their nest exit to an unfamiliar, adjacent arena, or the combination of an active and a passive outward leg during the outward journey to the centre of the animals' own arena. During their return to the nest, either the hamsters did not take into account at all the direction of the passive translation, or if they did, the compensation was only limited. These results are discussed in relation to the animals' capacity to assess 1) an active outward journey through the availability of different categories of self generated cues, and 2) a passive outward journey predominantly on the basis of vestibular signals. A final series of experiments showed that under certain conditions, the hamsters commit systematic homing errors which can be attributed to their failure to initiate the registration and computation of path dependent cues at the right instant in time and space.