Characterising ecological resource utilization by the endangered Egyptian vulture in Oman to better manage and mitigate electrocution risk

Abstract

Electrocution is a threat to birds and can undermine their conservation status. We tracked 15 globally endangered Egyptian vultures (Neophron percnopterus) in Oman and used Resource Selection Functions (RSFs) to identify habitats important to vultures and locate places where electrocution risk is high. During daytime vultures selected rugged areas with low vegetative cover, and habitats near roads, waste disposal sites, and both high (>50 kV, large pylons) and medium voltage electricity infrastructure. At night vultures also selected rugged habitats with scarce vegetation. At night high voltage infrastructure was selected, especially in areas of relatively low ruggedness at higher elevations; medium voltage infrastructure was avoided at night. The pattern of infrastructure use suggested that vultures were using large pylons for night-time roosting, but used both large pylons and smaller poles for perching during the day. 54.2 % of 11–33 kV powerlines in the study area were within the top six habitat suitability categories, which also contained 87.3 % of 34,778 vulture daytime test locations. Retrofitting powerlines overlapping the highest suitability zones would have the largest immediate impact. Areas surrounding landfills were also important: 10.34 % of all test locations were located within 2 km of landfills, which contained only 14.5 km of 11–33 kV lines. Targeting these areas would provide high impact at low cost. These maps are particularly useful in Oman because it is a stronghold for resident endangered large birds (i.e., Egyptian vulture, lappet-faced vulture Torgos tracheliotos) and an important winter destination for endangered steppe eagles (Aquila nipalensis).