Avian mortality associated with medium-voltage distribution lines in selected regions of Armenia: results of a pilot survey

Electrocution on medium-voltage distribution lines is a globally recognized threat to birds, yet data from the South Caucasus remain scarce. In Armenia, the magnitude and spatial distribution of this impact have not previously been assessed through systematic field surveys. This pilot study evaluated bird electrocution in selected regions of the country during the 2024 breeding and autumn migration periods. Surveys covered approximately 114 km of 10 kV overhead power lines (OPLs) (2,071 poles) across Armavir, Ararat, Kotayk, and Shirak provinces. Transects were walked along a 40 m search belt, and all carcasses discovered were documented, with species identification, pole type, and geographic coordinates being recorded. Given resource constraints, following initial surveys, the study prioritised concrete poles over wooden ones as the former were identified as presenting a potentially higher mortality risk. In total, 252 electrocuted birds representing 15 identified species were recorded. Mortality was markedly higher during autumn migration in Shirak (228 cases) than during the breeding season in other surveyed regions (24 cases), although this contrast may reflect both seasonal patterns and regional landscape differences. Corvids and small- to medium-sized diurnal raptors comprised the majority of recorded casualties. Spatial mapping revealed distinct mortality clusters, particularly around Arpi Lake National Park and in open steppe–agricultural landscapes with limited natural perching structures. Informal carcass persistence observations suggested prolonged detectability of large raptor remains. The results indicate that electrocution on medium-voltage lines represents a concentrated and potentially significant source of avian mortality in parts of Armenia, underscoring the need for targeted mitigation and systematic monitoring.