Demographic Risk to Eagles from Anthropogenic Causes of Death

Human actions effect wildlife in both indirect and direct ways. Indirect processes – habitat loss, climate change, reductions in reproductive rates – are often difficult to quantify. However, direct processes that cause death or nest failure are empirically measurable. A study of ~400 tracked Golden Eagles (Aquila chrysaetos) from 1997–2013 assessed causes of death of golden eagles in North America. From 34–63% of recorded fatalities were caused by humans. The most common anthropogenic causes of death of golden eagles were secondary poisoning, shooting, electrocution, and collision with vehicles or wind turbines. However, other sources of death – especially trapping and lead poisoning – were also regionally important. In total, survival rates of golden eagles in North America would be ~10% higher without human-caused deaths and this population likely is held below the carrying capacity by human-caused fatalities