Mongolian distribution power lines and raptor electrocutions

In September 2007 we visited distribution pole lines in the Mongolian steppe to access their risks to raptors. Distribution power lines in the Mongolian grasslands are used extensively by raptors. Nesting on utility poles also is common. Currently there is a trend to substitute older Russian-built wood pole electrical structures with Chinese-built concrete poles with grounded metal crossarms. Accordingly, both older distribution line sections constructed with wood poles and newer lines constructed with concrete poles were sampled. Although wood pole configurations can be quite lethal (one pole had 8 recent carcasses and had previously killed 26 birds), these configurations occurred relatively infrequently. In contrast, every inspected distribution concrete pole was potentially lethal. The concrete poles were built with grounded metal crossarms, resulting in greatly reduced phase-to-ground clearances. We inspected 527 concrete poles and detected 68 bird carcasses at pole bases. Although power lines can provide positive benefits for raptors, the trend to use concrete poles with metal crossarms in the Mongolian steppe outweighs positive benefits. If concrete poles are to be used in raptor habitat, alternative construction methods should be substituted, such as the use of suspended insulators.