The use of bromadiolone to control vole outbreaks is passed on to non-target species: implications for conservation policies

• Main Authors: López-Idiáquez, David, Martínez-Padilla, Jesús, López-Perea, Jhon J., Paz, Alfonso, Mateo, Rafael, Viñuela, Javier
• Format: Conference Object
• Language: unknown
• Published: 2015
• Subjects: Microtus arvalis
• Online Access: http://hdl.handle.net/10261/145918

Resumen del trabajo presentado a la 10th European Vertebrate Pest Management Conference, celebrada en Sevilla (España) del 21 al 25 de septiembre de 2015. Population fluctuations of rodents are common across Europe. Outbreaks of these populations are at the hub of conservation policies since they cause agricultural losses but increases abundances and reproductive outcome of their predators. This issue has become of particular relevance in southern Europe, where peaks of abundance of common voles (Microtus arvalis) results in agricultural damages, claiming an urgent control of these outbreaks by affected farmers. Local government encouraged the use of rodenticides, particularly bromadiolone, despite its effect on non-target species in wild populations is unknown. Here, we targeted two populations of common kestrels (Falco tinnunculus) in central Spain where bromadiolone was spread out to reduce the impact of vole outbreaks. Kestrels are a suitable species to tackle this issue because they feed mainly on voles in the study area. We explored first whether the use of bromadiolone to control vole outbreaks can be detected in blood of nestlings of kestrels breeding in affected areas and second, any potential association with body condition of these nestlings. Our results show that bromadilone was detected in blood in 17.6% of the sampled chicks (n=113) and that those chicks with bromadilone (mean±SE: 1.41±0.37 ng/ml) were in worse condition (lower body mass). According to our results, the use of bromadiolone to reduce vole abundance may have a knock-on effect on vole predators as this rodenticide can reach vole predators, perhaps worsening nestling condition, a key aspect for individual survival. We recommend, undoubtedly, dismissing the use bromadiolone as measure to control population outbreaks of voles. Peer Reviewed