Predicting barrier effects of transportation networks on Asian elephants: Implications for environmental impact assessment

The rapid proliferation of transportation networks (TNs) is a threat to
wide–ranged animals through habitat erosion, road–kill, and indirect
socio–ecological interaction. In most cases, environmental impact
assessments of TNs about animals are descriptive and targeted to direct
impacts of the “linear features”, while indirect and cumulative impacts
are relatively neglected. Using spatially explicit data of elephant–caused
damage during 2012–2015 in China, we quantified barrier effects of TN on
Asian elephants and predicted the effects under a TN expansion scenario
using maximum entropy algorithms. We found that TN acted as a strong
barrier even for the elephants that have inhabited highly fragmented
landscapes for years, with only 18% of the damage occurred on the crossed
side of roads. Also, the TN expansion will reduce elephant habitats,
exacerbating herd isolation and human–elephant conflict locally. Thus, we
suggest that mitigation of the conflicts should be integrated into future
environmental impact assessments.