Beyond the biological perspective of the road/fauna conflict: Vertebrates in the decision making of Spanish motorway operating companies

Abstract

Apart from safety issues, most scientific literature on the road/wildlife conflict has been focused on the analysis of the impacts of roads on animal populations. However, the integration of roads into ecosystems does not follow straightforwardly from such analyses as it depends on interactions between the infrastructure, the management operations and the biological communities in the surroundings. Thus, the involvement of companies that operate motorways is key in designing strategies to the environmental integration. From this perspective, we surveyed companies operating eight motorway sections in Spain (c. 225km in total) in order to identify: i) the types of fauna-related problems they faced, ii) the mitigation measures they take in response, and iii) the importance given to such problems in decision making, both subjectively and in terms of cost. A total of eight questionnaires were answered and six road-kill databases were gathered. Results show that the perception of wildlife problems and the implementation of mitigation measures varied between motorway sections, the highest-scored problems being road kills (cited in 100% of cases,), effects on the stability of roadslopes (50%), damage to fencing (50%) and carriageway deterioration (12%). Furthermore, the typology and extent of the problems differed significantly depending on the type of landscape crossed, with differences between those affecting motorways crossing urban zones and those seen at motorways in less disturbed areas. Companies adopt several mitigation and management actions that focus on these problems, with costs regarded as nonexistent or low in 62% of cases or moderate in 38%. The effectiveness of such actions is scarcely analyzed. In this regard, 38% of responders considered that the public image of their companies suffers from the road/wildlife conflict and 50% of them think that new mitigation measures should be implemented. In conclusion, and with the caution imposed by the small sample size, the survey shows i) road operating companies show disposition to take measures aimed at diminishing the road/wildlife conflict, and ii) highway management could benefit from improving scientific analyses of the implemented measures. Improved management could thus result from knowledge generated by their own monitoring of the effects of roads on wildlife.