Effectiveness of volatile irritants at reducing consumption of eggs by captive coyotes

  • Published source details Hoover S.E. & Conover M.R. (1998) Effectiveness of volatile irritants at reducing consumption of eggs by captive coyotes. Journal of Wildlife Management, 62, 399-405.


This study is summarised as evidence for the following.

Action Category

Use aversive conditioning to reduce nest predation by mammalian predators

Action Link
Bird Conservation
  1. Use aversive conditioning to reduce nest predation by mammalian predators

    A randomised, replicated and controlled experiment on ten captive coyotes Canis latrans (each tested with ten treatments over ten consecutive three day trials) in Utah, USA (Hoover & Conover 1998), found that no differences in food consumption, time delay before eating or amount of time spent eating when one of ten volatile chemicals was placed adjacent to food (so that they could be smelt but not ingested) at either the first or second exposure or in post-exposure trials. However, it also found that injecting eggs with 1 ml of one of ten volatile chemicals reduced the amount of egg consumed during both first and second exposures, compared to control eggs, for all chemicals except ammonia. However, egg consumption during post-treatment trials was unchanged following treatment and all eggs in post-treatment trials were opened. The ten chemicals tested were: allyl sulphide (garlic), ammonia, capsaicin (chilli pepper), chloroacetophenone (chemical mace), cinnamaldehyde (hot cinnamon), ethyl acetate, isoamyl nitrite (smelling salts), napthaldehyde (mothballs), pulegone (mint extract) and undecanone (commercially available dog repellent). When injected, pulegone, allyl sulphide and cinnamaldehyde reduced the amount of egg consumed significantly more than the other chemicals.


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