Embedded lead shot in European starlings Sturnus vulgaris: an underestimated hazard for humans and birds of prey

The poisoning of wild animals by lead (Pb) ammunition fired by hunters has been known for many decades, especially in the case of waterbirds. More recently, it has been demonstrated that raptors are also exposed to the risk of plumbism when feeding on unretrieved quarry that was wounded or killed by hunters. Further studies reveal that even humans can be subject to a significant Pb dose while consuming game animals killed by traditional ammunition. Given the relevance of this issue, several pieces of research have been carried out to assess frequency, dimension, and the number of Pb fragments embedded in the carcasses of ungulates, partridges, ducks, and other birds to evaluate the risk related to the consumption of game meat. In spite of their great importance as quarry species across southern Europe, until now, no data have been available on small passerines. To assess the quantity and type of Pb embedded in songbirds, we x-rayed 196 starlings shot in Italy and found Pb pellets and/or visible fragments in 118 carcasses (60.2 %).We counted 128 shotgun pellets in 85 carcasses. In 28 birds, we detected both whole pellets and lead fragments; in 33, we found only small fragments. By excising and weighing a sample of 20 shotgun pellets (diameter 1.35–1.99 mm), we calculated a Pb load of 3.75 g in the whole sample of 196 starlings, corresponding to an average of 27.32 mg/100 g of body weight. This is a conservative estimation, because fragments were not considered. Compared to game birds of a larger size, the starlings in our study had a lower amount of embedded Pb, but the shot pellets and fragments embedded in their tissueswere abundant and tiny. Given the results of previous studies, the quantity and level of fragmentation suggest that the risk of Pb poisoning cannot be ruled out for humans and birds of prey consuming the meat fromsongbirds killedwith traditional ammunition.