Completing a worldwide picture: preliminary evidence of lead exposure in a scavenging bird from mainland Australia
Science of the Total Environment
School of Science
Department of Biodiversity, Conservation and Attractions, DPAW
Lead toxicity from ammunition has been shown to be a threat to scavenging birds across the globe. Despite decades of research in Europe, North and South America, Asia and Africa, there have been no studies to investigate this phenomenon in Australia despite that continent having many species of scavenging birds and widespread shooting practices. We present preliminary evidence of lead exposure in Australia's largest bird of prey, the wedge-tailed eagles (Aquila audax) through analysis of bone and eggshell samples from south-western Australia. From 11 bone samples, three birds (27%) had lead levels exceeding literature thresholds for elevated levels (>6.75 ppm). From 36 eggshell samples, no samples had lead levels >0.5 ppm, suggesting some limitations for this matrix as an indicator of lead exposure. Isotope ratios suggested ammunition as a likely source of the lead found in bone samples with elevated lead levels but other potential sources of lead require further investigation. Our preliminary results demonstrate that lead exposure is occurring in scavenging birds in Australia, and like the rest of the world, is likely to be derived from ammunition. This study supports an urgent call for further research into this worldwide phenomenon in Australia. © 2019 Elsevier B.V.