title: Concentrations of anticoagulant rodenticides in stoats Mustela erminea and weasels Mustela nivalis from Denmark.
abstract: Anticoagulant rodenticides are widely used to control rodent populations but they also pose a risk of secondary poisoning in non-target predators. Studies on anticoagulant rodenticide exposure of non-target species have mainly reported on frequency of occurrence. They have rarely analyzed variations in residue concentrations. We examine the occurrence and concentrations of five anticoagulant rodenticides in liver tissue from 61 stoats (Mustela erminea) and 69 weasels (Mustela nivalis) from Denmark. Anticoagulant rodenticides were detected in 97% of stoats and 95% of weasels. 79% of the animals had detectable levels of more than one substance. Difenacoum had the highest prevalence (82% in stoats and 88% in weasels) but bromadiolone was detected in the highest concentrations in both stoat (1.290 μg/g ww) and weasel (1.610 μg/g ww). Anticoagulant rodenticide concentrations were highest during autumn and winter and varied with sampling method. Anticoagulant rodenticide concentrations were higher in stoats and weasels with unknown cause of death than in specimens killed by physical trauma. There was a negative correlation between anticoagulant rodenticide concentrations and body condition. Our results suggest that chemical rodent control in Denmark results in an extensive exposure of non-target species and may adversely affect the fitness of some stoats and weasels.
authors.affiliation: National Environmental Research Institute, Aarhus University, Department of Wildlife Ecology and Biodiversity, Grenåvej 14, DK-8410 Rønde, Denmark. elm@dmu.dk
authors.forename: Morten
authors.initials: M
authors.lastname: Elmeros
authors.forename: Thomas Kjær
authors.initials: TK
authors.lastname: Christensen
authors.forename: Pia
authors.initials: P
authors.lastname: Lassen
mesh_terms: D015110:4-Hydroxycoumarins / Q000378:metabolism; D000818:Animals; D000925:Anticoagulants / Q000378:metabolism*; D003718:Denmark; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000378:metabolism*; D004787:Environmental Pollution / Q000706:statistics & numerical data; D005260:Female; D008099:Liver / Q000378:metabolism; D008297:Male; D008907:Mink / Q000378:metabolism; D045969:Mustelidae / Q000378:metabolism*; D012378:Rodenticides / Q000378:metabolism*; D012621:Seasons
chemical_list: D015110:4-Hydroxycoumarins; D000925:Anticoagulants; D004785:Environmental Pollutants; D012378:Rodenticides; C021636:bromadiolone; C012903:difenacoum