Causes of death in different areas for Bonelli's Eagle Hieraaetus fasciatus in Spain

The Spanish Bonelli's Eagle populations have decreased markedly because of high mortality. We recorded 424 cases of dead eagles between 1990 and 1998 in Spain which after cross-comparison corresponded to 377 individuals. Elec trocution (55% of deaths), followed by direct persecution (26%) were the ma in causes of death. No differences in the cause of death were found between sexes. Non-adult eagles mostly died of electrocution whereas adults were m ainly the victims of persecution. A log-linear model showed that these diff erences were associated with a difference in tire spatial distribution of a ge classes, rather than to age or experience per se. Persecution ions the m ain cause of death in breeding areas and electrocution in non-breeding aura s. There were differences between regions: electrocution ions the main caus e in Catalonia and Central Spain (50% and 86% respectively) whereas direct persecution was the main cause in Levant and Northern Spain (52% and 43% re spectively). We recommend that steps are taken in order to reduce eagle mor tality, taking into account the differences between regions and areas.