Road networks represent a major disturbance for wildlife, and their continued development threat-ens biodiversity. Many mitigation measures show reliable results at reducing road mortality, alt-hough with high costs (e.g. fences and crossing structures). Inexpensive measures have been applied, but there is little proof of their effectiveness. Finding possible ways to reduce this impact should be a priority issue for road planners. Some animals may take advantage of roads as refugees (mostly small animals) or as easier hunting sites (birds of prey), which makes them vulnerable to vehicle collisions. Therefore, dissuasion measures should be implemented in such a way that prevail over these bene-fits. Here we tested the efficiency of monitoring and sound devices as an alternative method to
reduce wildlife road and electrocution mortality. We hypothesised that exposing animals to these stress levels will cause them to stay away from the devices and, consequently, from the road or elec-trical line. We made four prototypes: three dissuasion prototypes that include a motion detection system based on infrared sensors and a sound device; and one monitor prototype that includes a motion detector camera. Two dissuasion prototypes aimed to discourage mice from approaching roads and were placed on the ground on a road verge in southern Portugal. The third dissuasion pro-totype aimed to dissuade large birds from landing on an electrical pole and was placed in an electrical pole in Southern Portugal. The monitoring prototype aimed to record the approaching and be-haviour of large birds on the electrical pole with the dissuasion prototype, and it was placed pointed directly to the electrical pole. Whenever motion is detected, the devices started to play ultrasound (mice dissuasion prototypes), audible sound (large birds dissuasion prototype) or start recording (monitoring prototype). We counted the presence of animals at the spot 10-days before, and 10-days after the device was switched on (Before-After study): we sampled mice with Sherman traps, and every day we observed the dissuasion prototype and the monitoring prototype of large birds. Our results showed a reduction of animal approach as soon as the dissuasion prototypes were switched on, with fewer mice captures on the road verges and greater bird avoidance or reduction of length of stay on the electrical pole. The monitor prototype was able to detect with good accuracy most of the birds that landed on the electrical line. Wildlife detectors equipped with sound devices seem to be a useful measure to reduce the approaching of these species. The next steps would be to analyse if this avoid-ance will cause a significant road and electrocution mortality reduction and if this method can be adapted to others species or locations.
