Electrocution
Bird mortality by electrocution on power poles is a global problem that has become more prevalent in recent years as energy demand increases, resulting in infrastructure growth often in previously undeveloped areas. Electrocution associated with powerlines occurs when a bird comes into contact with two wires, one of which is live, or when it perches on a conductive pylon (for example, a metal structure) and comes into simultaneous contact with a live wire. Large species such as vultures, eagles and storks are particularly vulnerable. Electrocution risk can be very significant in old, badly designed and insulated poles and poorly sited power lines. Effective planning, design and mitigating measures can dramatically reduce the impact of energy infrastructure on avian populations.
Electrocution from powerlines is one of the key threats for Cape Vultures in South Africa with data suggesting that this cause of mortality makes a significant contribution to low juvenile and immature survival rates. Despite this, in certain situations, vultures might derive some benefit from the presence of power lines in relation to increased nesting, roosting sites and nursery areas, which may allow them to expand their range, especially if suitable mitigation measures can be taken to lessen the risk of electrocution.