title: The repelling effect of plant secondary metabolites on water voles, Arvicola amphibius.
abstract: BACKGROUND
  Water voles (Arvicola amphibius Linnaeus 1758) are abundant in most parts of Germany and other European countries. They are known to cause serious damage in fruit and horticulture as well as in agriculture. Currently available repellents, scaring devices and household remedies are mostly inefficient. Tests were conducted to establish whether water voles can be repelled using plant secondary metabolites. These compounds are produced by many plant species as part of their defence against herbivores and pathogens.
  
  
  RESULTS
  In this study, 12 volatile substances were tested in T-maze trials. The voles could choose between a test box including a test substance and a control box without odour. The extracts were considered to be repellent if the test box was avoided. Five potential repellents were identified: the essential oils of black pepper oil, Chinese geranium oil and onion, as well as the pure substances methyl nonyl ketone and n-valeric acid. Application of a combination of black pepper oil, Chinese geranium oil and methyl nonyl ketone did not increase efficacy.
  
  
  CONCLUSIONS
  The identification of an effective water vole repellent could help to reduce damage to crops. It may also minimise the use of kill traps and of rodenticides, which will be of benefit for non-target organisms.
authors.affiliation: Vertebrate Research, Institute for Plant Protection in Horticulture and Forestry, Federal Research Centre for Cultivated Plants, Julius Kühn-Institute, Münster, Germany. d.fischer@posteo.de
authors.forename: Daniela
authors.initials: D
authors.lastname: Fischer
authors.forename: Christian
authors.initials: C
authors.lastname: Imholt
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Pelz
authors.forename: Michael
authors.initials: M
authors.lastname: Wink
authors.forename: Andreas
authors.initials: A
authors.lastname: Prokop
authors.forename: Jens
authors.initials: J
authors.lastname: Jacob
mesh_terms: D000818:Animals; D003411:Arvicolinae / Q000502:physiology*; D009822:Oils, Volatile / Q000378:metabolism / Q000494:pharmacology*; D010938:Plant Oils / Q000378:metabolism / Q000494:pharmacology*; D010944:Plants / Q000737:chemistry / Q000378:metabolism; D012375:Rodent Control / Q000295:instrumentation / Q000379:methods*; D012378:Rodenticides / Q000494:pharmacology*
chemical_list: D009822:Oils, Volatile; D010938:Plant Oils; D012378:Rodenticides