Position of operant cost affects blue foxes' time budget between sand floor and mesh floor

The aim of the study was to assess whether positioning of the operant cost would affect blue foxes' (Vulpes lagopus) behaviour and time budget between a mesh floor and sand floor. We built fourteen test apparatuses, six consisting of two fox cages with a mesh floor in both cages and eight with a mesh floor in one cage and a sand floor in the other cage, A cost could be imposed to pass through one-way doors between the cages. The effect of changing the cost to move from the mesh floor to the sand floor or from the sand floor to the mesh floor or between the two mesh floors was examined in 28 juvenile male blue foxes. The foxes' time allocation between the cages was recorded for four different costs. The foxes' behaviour was analysed in more detail at the lowest and highest costs. The visit duration increased considerably when leaving the cage became costly, but did not markedly change when entering was costly. The foxes spent less time on the sand floor than on the mesh floor. The foxes preferred to rest on the mesh floor, but rested also on the sand floor when there was a cost associated with leaving the sand floor. The sand floor stimulated digging, rooting and play. In conclusion, both positioning of the cost and the floor material affected blue foxes' time budget between the two cages. (C) 2008 Elsevier B.V. All rights reserved.