High Levels of Blood Lead in Griffon Vultures (Gyps fulvus) from Cazorla Natural Park (Southern Spain)

Abstract

The blood lead of 23 griffon vultures (Gyps fulvus) trapped in 2003 was analyzed in order to evaluate exposure to lead in the vulture population of Cazorla Natural Park (in southern Spain). In 2001 the use of leaded gasoline in vehicles was banned in the European Union; however, lead ammunition is still used in Spain in big-game hunting for red deer, fallow deer, mouflon, and wild boar, which are ingested by vultures from September to March. The mean concentration of lead in blood was 43.07 6 31.96 g/dL with a range of 17.39–144.80 g/dL. Only two vultures had lead levels below 20 g/dL, and two others had blood lead concentrations close to 150 g/dL. In view of the results, we think the population of vultures from Cazorla Natural Park is suffering subclinical exposure to lead, with some individuals exposed to high toxicity risk. We concluded that ingestion of lead in the metallic form alone is sufficient to produce these blood lead concentrations, and we recommend the prohibition of lead ammunition for big-game hunting in order to preserve the vulture population.