Is out of sight out of mind? The effects of resource cues on motivation in mink, Mustela vison
Publication Type: |
Journal Article |
Year of Publication: |
2003 |
Authors: |
Harriet Warburton, Georgia Mason |
Publication/Journal: |
Animal Behaviour |
Keywords: |
behavior motivation, mink |
ISBN: |
0003-3472 |
Abstract:
Measuring strength of preference is a powerful tool in welfare research. However, animals’ preferences in so-called demand experiments may be influenced by stimuli from the test resources (e.g. olfactory or visual cues), leading to motivations different from those of the `applied’ animals who are not so exposed. Resource cues could act as eliciting stimuli, enhancing motivation, or they could supply information so that working for closer access to a resource becomes redundant. We assessed the priorities of mink in both a typical closed economy demand set-up (Cues, i.e. resource cues present when preference is expressed) and one where resource cues were distant and screened at the choice point (No Cues). Six mink were tested in both treatments, and their motivation to reach four resources (Food, Bath, Unpredictable Social Contact, Toy) was assessed via their responses to increased access costs (weighted doors). Of five measures, only the maximum price paid was unaffected by treatment. For the other four measures, cue availability affected the motivation to reach some resources but not others: there were significant treatment×resource effects on baseline visit rate, visit elasticity and consumer surplus, and a similar but nonsignificant trend for expenditure rate. The rank order of preferences was also affected by treatment: Food was most preferred in both treatments, but motivation for Toys and possibly also Unpredictable Social Contact declined in the No Cues treatment. This result has implications for the mink welfare debate and also for the design of valid preference experiments. We suggest that different designs and measures of motivation vary in their suitability for addressing the two types of applied questions that use motivational data.