Avian mortality along power lines in Pokhara valley, Nepal.
Objective: To quantify avian mortality associated with 11 kV distribution power lines in the Pokhara Valley, Nepal, and evaluate the ecological and infrastructure-related drivers of collision and electrocution. The study aimed to identify high-risk conditions and provide evidence-based recommendations for mitigating power line impacts on bird populations.
Methodology: Systematic carcass surveys were conducted along randomly selected 1.5 km segments of 11 kV distribution power lines. Bird carcasses were identified to species level, and mortality was classified as resulting from either collision or electrocution based on field evidence. Habitat variables, including vegetation proximity, distance to water bodies, bird abundance, and power pole characteristics, were quantified to assess their influence on mortality patterns. Statistical analyses were performed to identify factors associated with increased mortality risk.
Findings: The surveys documented 61 avian fatalities representing 15 species, with electrocution accounting for the majority of mortality events. Raptors constituted a substantial proportion of recorded fatalities, including globally threatened species such as the Critically Endangered White-rumped Vulture (Gyps bengalensis) and the Endangered Egyptian Vulture (Neophron percnopterus). Mortality risk was positively associated with increased bird abundance and the proximity of power lines to vegetation and aquatic habitats. Infrastructure lacking adequate insulation exhibited a significantly higher incidence of electrocution. These findings identify priority areas and infrastructure characteristics for targeted mitigation.
Learnings: Conducting this research strengthened my confidence as an early-career conservation scientist by developing my field, analytical, and scientific writing skills and demonstrating how research can inform real-world conservation decisions.