Predicting indirect effects of transportation network expansion on Asian elephants: Implications for environmental impact assessments

The rapid proliferation of transportation networks (TNs) threatens the viability of species with wide geographic ranges via habitat fragmentation, road kill, and indirect socio‐ecological interactions. Environmental impact assessments of TNs are mostly descriptive and focus on the direct impacts of the linear features of TNs, while the indirect and cumulative impacts are largely neglected. Using spatially explicit data of elephant‐caused damage from 2012 to 2015 in southwest China, we quantified the barrier effects of TNs on Asian elephant populations and predicted future patterns of damage under a TN expansion scenario using maximum entropy algorithms. The TNs acted as a strong barrier for the elephants, even in herds that have inhabited highly fragmented landscapes for years. Overall damage patterns were highly asymmetric around roads, with only 18% of events occurring on the far side of roads (relative to the core home range). Models predicted that TN expansion would reduce elephant habitats, exacerbating herd isolation and human–elephant conflict locally. Thus, we suggest that future environmental impact assessments should integrate mitigation of indirect conflicts. Abstract in Chinese is available with online material.