Lead poisoning of animals due to ingestion offragments from lead-based ammunition in carcasses and offalof shot wildlife is acknowledged globally and raises greatconcerns about potential behavioral effects leading to increasedmortality risks. Lead levels in blood were correlated withprogress of the moose hunting season. Based on analyses oftracking data, we found that even sublethal lead concentrationsin blood (25 ppb, wet weight), can likely negatively affectmovement behavior (flight height and movement rate) of freeranging scavenging Golden Eagles (Aquila chrysaetos). Leadlevels in liver of recovered post-mortem analyzed eaglessuggested that sublethal exposure increases the risk ofmortality in eagles. Such adverse effects on animals are probably common worldwide and across species, where game huntingwith lead-based ammunition is widespread. Our study highlights lead exposure as a considerably more serious threat to wildlifeconservation than previously realized and suggests implementation of bans of lead ammunition for hunting.