A negative association between bromadiolone exposure and nestling body condition in common kestrels: management implications for vole outbreaks.
BACKGROUND
Vole outbreaks have been extensively described, along with their impacts on humans, particularly in agricultural areas. The use of rodenticides is a common legal practice to minimise crop damage induced by high vole density for biocidal use. However, rodenticides can have negative direct and indirect impacts on non-target species that feed on voles. We studied whether the use of a second-generation anticoagulant rodenticide (SGAR), bromadiolone, can be detected in the blood of fledglings of wild common kestrels Falco tinnunculus in two areas of central Spain, exploring its possible indirect effects.


RESULTS
We found that 16.9% of fledglings had a detectable concentration of bromadiolone in their blood, with an average concentration of 0.248 ± 0.023 ng mL-1. Fledglings with bromadiolone in their blood, regardless of the concentration, had 6.7% lower body mass than those without detectable bromadiolone.


CONCLUSIONS
The use of bromadiolone was detectable in the blood of alive non-target species. Detected bromadiolone in blood may reduce the body condition of nestlings, potentially reducing their fitness. The source of bromadiolone found in nestlings needs to be determined in future studies to derive accurate management advice. However, we urge the discontinuation of official SGAR distribution to farmers and their use in agrarian lands to minimise damage of voles on crops, particularly where common kestrels breed, and encourage the use of alternative effective practices. © 2016 Society of Chemical Industry.
UMIB - Research Unit of Biodiversity (CSIC/UO/PA), University of Oviedo, Mieres, Spain.|Estación Biológica de Doñana, Seville, Spain.|Centre d'Etudes Biologiques de Chizé (CEBC), Université de La Rochelle, Villiers-en-Bois, France.
Jesús
J
Martínez-Padilla
Estación Biológica de Doñana, Seville, Spain.|Department of Evolutionary Ecology, Museo Nacional de Ciencias Naturales de Madrid (CSIC), Madrid, Spain.
David
D
López-Idiáquez
Instituto de Investigación en Recursos Cinegéticos (IREC-CSIC-UCLM-JCCM), Ciudad Real, Spain.
Jhon J
JJ
López-Perea
Instituto de Investigación en Recursos Cinegéticos (IREC-CSIC-UCLM-JCCM), Ciudad Real, Spain.
Rafael
R
Mateo
Grupo de Rehabilitación de la Fauna Autóctona y su Hábitat (GREFA), Majadahonda, Madrid, Spain.|Department of Zoology, Stockholm University, Stockholm, Sweden.
Alfonso
A
Paz
Instituto de Investigación en Recursos Cinegéticos (IREC-CSIC-UCLM-JCCM), Ciudad Real, Spain.
Javier
J
Viñuela
D015110:4-Hydroxycoumarins / Q000009:adverse effects / Q000097:blood*; D000818:Animals; D000831:Animals, Newborn; D000925:Anticoagulants / Q000009:adverse effects / Q000097:blood*; D003411:Arvicolinae; D001835:Body Weight / Q000187:drug effects; D046093:Falconiformes / Q000097:blood* / Q000254:growth & development; D020387:Food Chain; D010571:Pest Control / Q000379:methods; D012378:Rodenticides / Q000009:adverse effects / Q000097:blood*; D013030:Spain
D015110:4-Hydroxycoumarins; D000925:Anticoagulants; D012378:Rodenticides; C021636:bromadiolone
poisoning; raptors; rodenticide; voles; wild populations