Using Multi-Point Activity Surveys for identification of bat commuting routes and selection of candidate urban dark corridor sites

Abstract Context. In the complex balance between the landscapes of energy and fear, urban artefacts impact the routes taken by commuting bats. Little is known about the movements of urban bats, with mitigation efforts seldom being evidence-based. Knowledge of existing bat movements to inform urban sustainability is crucial. Objectives. We applied the Multi-Point Activity Survey (MultiPAS) method in two case studies to quantify the use of nightly commuting routes used by bats in an urban landscape and to use those data to select candidate dark corridor sites and key points for retention of vegetation at crossing points. Methods. Two models of MultiPAS were tested on urban canals, comprising one 2.8 km linear site and five canal junctions in the West Midlands, UK. Results. The linear model identified important bat ingress and egress points, and a key candidate dark corridor site through a residential area. The junction survey model yielded candidate dark corridors at three junctions, and a crossing point for the retention of vegetation. The combined data also identified two major feeding areas for bats. Conclusions. The knowledge of existing commuting routes and crossing points is invaluable in urban planning for bat conservation. The knowledge gained by using MultiPAS methods would allow local authorities to select appropriate dark corridor sites in effective, evidence-based and landscape-scale conservation efforts.