Talk Wildlife collision data as an indicator of the effectiveness of mammal mitigation measures across the National Road Network in Ireland

Over the past two decades, the national road network in Ireland has increased substantially. Transport Infrastructure Ireland (TII) recognises that together with improved road systems, increased traffic volumes and higher traffic speeds, it is likely that the number of collisions with wildlife across Ireland will increase into the future. Collisions between road traffic and wildlife pose a threat to animal welfare and can also have major safety and cost implications. When constructing national road schemes in Ireland, it is standard best practice to integrate mammal mitigation measures into the early planning stages to ensure impacts on wildlife are limited and that safety is enhanced by reducing collisions between wildlife and vehicles. Over the past 15 years, mammal underpasses and mammal resistant fencing have been built into major roads in Ireland. The suitability/effectiveness of such mitigation measures has been the subject of a major study over the last five years by recording mammal activity in the underpassess and undertaking species-specific road kill analysis across the major road network.

TII are developing standardized protocols for the collection of road kill data on the Irish national road network. Species-specific data collection is supported by the use of roadkill collection apps which are uploaded onto Geographic Information Systems (GIS). TII is in a unique position in that it has operatives out patrolling the major interurban routes on a daily basis. The practice of daily surveying increases the likelihoodof the accurate capture of road mortality data as it minimises the time in which scavengers may remove a carcass as well as reducing the likelihood of a loss of evidence of a wildlife-vehicle collision due to adverse weather conditions or the number of vehicles passing over a carcass. Daily road monitoring and a reduced interval time between surveys also allows for increased sampling frequency which minimizes bias in road mortality estimates thus allowing for a more robust statistical analysis of the data.

Species-specific data will be presented here on traffic kills and sightings across the network. This information is vital for producing a standardized protocol for risk assessments and for isolating road kill hotspots across the network. In particular, the road kill hotspots identify sections of the network which allows for a detailed assessment of the suitability and effectiveness of the prescribed mammal mitigation measures. Detailed assessments of such mitigation measures often reveal a range of issues that compromises their functionality, resulting in wildlife collisions on the network. Examples of such issues will be outlined in this presentation.

Wildlife, roads, mitigation, management, maintenance, standards, collisions, mortality