Electrocution in Large Eagles in Southwest Spain: A Retrospective Study (1996–2008)
Electrocution is one of the most common causes of mortality in eagles in Spain, representing one of the main threats to endangered species.2,4,5 We present a 12-year study of electrocution in four large eagle species admitted to a rehabilitation center in southwest Spain: Spanish imperial eagle (Aquila adalberti), Bonelli’s eagle (Hieraaetus fasciatus), golden eagle (Aquila chrysaetos), and short-toed eagle (Circaetus gallicus). A total of 115 eagles were admitted with lesions consistent with electrocution and/or found dead under a power line/pole. Females (57%) suffered electrocution more frequently than males (43%). Most (72%) of the animals were received dead. Only 9% of the eagles admitted alive were released, whereas 31% were euthanatized, 27% died, and 27% were kept as non-releasable individuals. Forty percent of the imperial and golden eagles had lesions on both legs, whereas Bonelli’s eagles most commonly presented with lesions on wings and leg(s).
Electrocution continues to be one of the main causes of mortality of eagles in Spain, though major efforts are made by governments to implement mitigating measures.6 Because of their large size and the lack of natural perches higher than the electric poles, these species are more susceptible to suffer an electrocution.3 The higher mortality among females in the golden and imperial eagles supports size difference in dimorphic species as one among other factors potentially influencing higher female mortality.1 The results of this study provide evidence that the patterns of electrocution observed in the different species can be important for determining the best mitigating measures to apply.
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6. 2008. Real Decreto 1432: Medidas para la protección de la avifauna contra la colisión y la electrocución en líneas eléctricas de alta tensión, BOE.