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Providing evidence to improve practice

Action: Use repellent on slug pellets to reduce non-target poisoning Terrestrial Mammal Conservation

Key messages

Read our guidance on Key messages before continuing

  • One study evaluated the effects on mammals of using repellent on slug pellets to reduce non-target poisoning. This study was in the UK.




  • Use (1 study): A replicated, controlled study in the UK found that, at some concentrations, food treated with a bitter substance was consumed less by wood mice but not by bank voles or common shrews.

Supporting evidence from individual studies


A replicated, controlled study (year not stated) in an agricultural area in the UK (Kleinkauf et al. 1999) found that treating food with a bitter substance (Bitrex™; as a trial of its efficacy for deterring toxic slug pellet consumption) reduced consumption by wood mice Apodemus sylvaticus at some concentrations but did not change consumption rates of bank voles Clethrionomys glareolus or common shrews Sorex araneus. Wood mice avoided food treated with Bitrex at 100 ppm and 300 ppm but showed no avoidance at 50 ppm or 500–1,740 ppm (data not presented). Bank voles and common shrews showed no avoidance of food treated with Bitrex at 100 ppm or 300 ppm (data not presented). Wild small mammals were contained within small enclosures. Wood mice and bank voles were offered barley Hordeum vulgare. Common shrews were offered fly pupae. Food was sprayed with the Bitrex solution. Trails ran for eight hours overnight (wood mouse) or six hours night or day (bank vole and common shrew) with treated food only and with choices of treated and untreated food.

Referenced papers

Please cite as:

Littlewood, N.A., Rocha, R., Smith, R.K., Martin, P.A., Lockhart, S.L., Schoonover, R.F., Wilman, E., Bladon, A.J., Sainsbury, K.A., Pimm S. and Sutherland, W.J. (2020) Terrestrial Mammal Conservation: Global Evidence for the Effects of Interventions for terrestrial mammals excluding bats and primates. Synopses of Conservation Evidence Series. University of Cambridge, Cambridge, UK.