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Use of conditioned taste aversion to reduce vertebrate pest problems - VC0406

Conditioned taste aversion (CTA; the tendency of animals to associate the taste of a new food with a subsequent illness) has the potential to modify problem behaviour of vertebrate wildlife. If an animal’s food is adulterated with a combination of a flavourless compound that induces a mild illness together with a strong harmless flavour, then the animal will ascribe its subsequent nausea to the flavour. In this study, the applicability of CTA for the management of predation of birds by foxes and nuisance behaviour by badgers will be investigated. Compounds will be identified that are most effective at inducing mild illness and aversion. Initially, candidate materials will be screened in rats, with the optimum candidates being validated in foxes and the appropriate doses determined. Effect of previous experience of a flavour by individual foxes on subsequent ability of that flavour to induce a CTA response will be quantified. Behavioural context of the aversions will be assessed in rats, and subsequently in foxes, to determine whether CTA can prevent animals from hunting as well as consuming food. Longevity of the CTA in foxes and badgers will be quantified in order to assess the timescale over which animals that have been successfully conditioned will need subsequent periods of reinforcement. Finally, importance of context of a CTA will be established; presence of a CTA generated amongst badgers to an odour in one context (e.g. at the sett) will be investigated in other sites (e.g. a garden).
1. Identify the most effective compounds and doses required to induce mild illness and aversion by initially screening candidate materials in laboratory rats and then validating optimum candidate in foxes (Start: April 1995, Finish: April 1996). 2. Quantify the effect of previous experience of a flavour by individual foxes on the subsequent ability of that flavour to generate a CTA (Start: April 1996, Finish: September 1996). 3. Assess whether rats and then foxes can be prevented from seeking as well as consuming food to which they have a CTA (Start: December 1995, Finish: December 1996). 4. Quantify the persistence of CTA's in foxes and badgers (Start: July 1996, Finish April 1997). 5. Establish whether a CTA generated amongst badgers to an odour in one context (e.g. at the sett) is generalised to the presence of that odour in another (e.g. a garden) (Start: December 1996, Finish: March 1998).
Time-Scale and Cost
From: 1995

To: 1998

Cost: £196,533
Contractor / Funded Organisations
Central Science Laboratory
Fields of Study
Wildlife Management