Kernel intensity estimation of the density of crossing bats across the A66 site . Gaussian kernel and bandwidth of 1 m used (n = 1078). The section of severed woodland at the A66 site is shown. The gantry is located at distance 0 m (height marked by square), and the pre-construction commuting route at 10–15 m. ‘Unsafe’ crossing heights are located below the dashed line. The dotted line marked verge shows the decrease in verge height above the road from left to right.