A preliminary investigation of persistent pollutants in Eurasian Curlew Numenius arquata eggs in Ireland

Persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and other organochlorine compounds (OCs), as well as metals, have deleterious impacts on birds. Bird eggs are considered a favourable matrix for monitoring pollutants. The Eurasian Curlew Numenius arquata is classified as Near Threatened by the IUCN and is Red-Listed (high conservation concern) in Ireland. There are few studies of contaminants in Curlew eggs, most likely a result of their conservation status and the difficulty in obtaining samples. Abandoned eggs of Curlew from multiple sites were analysed for a wide variety of organic pollutants (Σ16PCB, Σ6PBDE, ΣHCH, ΣCHL, ΣDDT) and metals (Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Ag, Cd, Pb, Hg). Concentrations of pollutants in this study are lower than historical studies in Curlew eggs (PCBs, DDT) and are within the range of contemporary, internationally reported values for other wader species. Although this is a preliminary study, levels of persistent pollutants in these Curlew eggs fall below all existing thresholds for adverse effects in other species, and it is unlikely these pollutants are having an immediate impact on the breeding success of Curlew in Ireland.