ON COMPARING THE BEHAVIOUR OF ZOO HOUSED ANIMALS WITH WILD CONSPECIFICS AS A WELFARE INDICATOR J S Veasey, N K W aran and R J Young t Institute of Ecology and Resource Management, University of Edinburgh, West Mains Road, The King's Buildings, Edinburgh EH9 3IG t Contact for correspondence and requests for reprints: Animals Department, Edinburgh Zoo, Murrayfield, Edinburgh EH12 6TS Abstract Animal Welfare 1996, 5: 13-24 It is commonly assumed that animals suffer if they cannot perform behaviours seen in wild conspecifics. Although comparisons with the behaviour of wild conspecifics are a popular method of assessing the welfare of captive animals, their validity has not been fully assessed. Homeostatic models of motivation suggest that many behaviours are stimulus driven rather than internally generated. Thus, it is possible that the non-peiformance of some wild-type behaviours does not necessarily compromise animal welfare, unless welfare is defined as being compromised by such non-peiformance. The flexibility of wild animal behaviour and the fact that animals free to peiform the complete range of wild behaviours can suffer, must also put into the question the validity of such compansons. Technical criticisms also anse when one considers the difficulty of constructing accurate and unbiased time budgets for wild animals. It is possible that the expressions of wild-type behaviours correlate with enhanced welfare, rather than cause enhanced welfare. Thus, if the consequences of behaviour are more important than the expression of behaviour itself, environmental enrichment does not necessarily need to rely upon the performance of wild-type behaviours for the improvement of animal welfare. Therefore, although behavioural comparisons with wild animals can be considered as potentially useful indicators of behavioural differences, they cannot always be relied upon to give an objective assessment of animal welfare. To make an assessment of welfare, behavioural comparisons with wild animals should be used in conjunction with other techniques to demonstrate that the consequences of non-peiformance of wild behaviours results in impoverished welfare. Keywords: animal welfare, behaviour, behavioural needs, captive, motivation, wild Introduction The behaviour of a wild animal, which we define as: 'the behaviour expressed by an animal subject to environmental and evolutionary pressures with minimal human intervention'. is often used as a bench mark by which the welfare of captive animals can be assessed (Thorpe 1967; Heidiger 1969; Lindburg 1988; Fraser & Broom 1990; Chamove & Anderson 1989; Chamove 1989; Shepherdson 1989a; Bayne et aI1992). Thorpe (1965) and Martin (1979) argue that animals have to perform the full repertoire of behaviours shown by free-living conspecifics, for suffering to be avoided. Thorpe (1967) further argued that animals suffer © 1996 Universities Federation for Animal Welfare Animal Welfare 1996, 5: 13-24 13