Using occupancy analysis to validate the use of footprint tunnels as a method for monitoring the hedgehog Erinaceus europaeus

Indirect survey methods are often used in studies of mammals but are susceptible to biases caused by failure to detect species where they are present. Occupancy analysis is an analytical technique which enables non‐detection rates to be estimated and which can be used to develop and refine novel survey methods. In this study, we investigated the use of footprint tunnels by volunteers as a method for surveying occupancy of sites by hedgehogs Erinaceus europaeus. The survey protocol led to a very low non‐detection rate and could reasonably be used to detect occupancy changes of 25% with statistical power of 0.95 in a national survey.