Mitigating the impacts of road networks
In addition to the long-standing challenges of ensuring the peaceful coexistence of people and large carnivores, a new category of threats has emerged in recent decades: those associated with major infrastructure developments, particularly large transport networks that pass through areas which until recently remained relatively undisturbed natural ecosystems. While roads have always played a vital role in human development and connectivity, they also have significant impacts on biodiversity that should be mitigated wherever possible.
The fragmentation of natural habitats is one of the most serious threats facing large carnivores. Roads and other linear infrastructures create artificial barriers that disrupt wildlife movement, reduce habitat connectivity, and can isolate local populations. At the same time, the extensive distances travelled by species such as bears and wolves, combined with their large body size, significantly increase the risk of vehicle collisions. These accidents threaten both wildlife conservation and public safety, making wildlife-friendly transport infrastructure an essential component of modern road planning and management.
At Callisto, we work to eliminate or minimise these impacts through long-term efforts to ensure that environmental protection is fully integrated into infrastructure planning and development.
Through scientific research and evidence-based advocacy, Callisto has contributed to improving both the alignment and technical design of major roads by promoting the adoption of effective wildlife mitigation measures. These include wildlife exclusion fencing to prevent animals from accessing roadways, as well as the construction of green bridges (wildlife overpasses) and underpasses that maintain habitat connectivity and allow animals to move safely across fragmented landscapes.
Callisto has also helped reduce the impacts of road networks through the installation of wildlife warning signs for motorists, optical and audio-visual wildlife reflectors, and the testing of innovative solutions such as wildlife detection and warning systems, which alert drivers or deter animals when vehicles are approaching.
Since its establishment, Callisto has developed extensive expertise in the field of transport infrastructure and wildlife conservation, implementing practical measures that have demonstrated measurable results. One notable example is the installation of bear exclusion fencing along the A29 motorway, which successfully reduced wildlife–vehicle collisions involving brown bears on that section of road to zero.
Related projects
LIFE SAFE-CROSSING (LIFE17 NAT/IT/000464)
From the Greek side, Callisto, COSMOTE, Egnatia Odos S.A., and the Region of Western Macedonia are partners in the LIFE SAFE-CROSSING project, an international initiative involving organisations from Italy, Romania, and Spain.
The project aims to reduce the environmental impacts of road infrastructure on priority wildlife species across four European countries: the Marsican brown bear (Ursus arctos marsicanus) and the grey wolf (Canis lupus) in Italy, the Iberian lynx (Lynx pardinus) in Spain, and the brown bear (Ursus arctos) in Greece and Romania.
These species are severely affected by transport infrastructure through both wildlife–vehicle collisions and the barrier effect, which restricts animal movement and fragments habitats. To address these challenges, the project builds on the experience gained through the successful LIFE STRADE project (LIFE11 BIO/IT/000072), during which an innovative wildlife–vehicle collision prevention system was successfully deployed at 17 locations in central Italy. The project also highlighted that one of the main causes of wildlife collisions is the low level of driver awareness regarding the presence of wild animals on roads.
The LIFE SAFE-CROSSING project focuses on the following objectives:
-Demonstrate the application of innovative animal–vehicle collision (AVC) prevention systems in new pilot areas.
-Reduce the risk of collisions involving priority protected species.
-Improve habitat connectivity and facilitate the safe movement of wildlife across transport corridors.
-Increase driver awareness of wildlife collision risks within the project areas.
The project brings together 13 partners, including public authorities, private companies, and environmental NGOs. The participation of the Province of Terni (Italy) ensures the transfer of expertise and best practices developed through the LIFE STRADE project to the new implementation areas.
Learn more about the project: https://life.safe-crossing.eu/
The Road Is Coexistence project was implemented between June 2020 and January 2022 with a total budget of €49,891.55. It was fully funded by the Green Fund of Greece through the “Innovative Actions with Citizens” funding programme.
The project was coordinated by Callisto, in partnership with the Alterthess journalists’ cooperative, which led the production of the project’s mini-documentary, and two departments of the University of Western Macedonia: the Department of Electrical and Computer Engineering, which supported the development of the mobile application, and the Department of Fine and Applied Arts, which developed the project’s visual identity and communication materials.
The project’s objective was to design and implement four innovative awareness and public engagement actions aimed at reducing the impacts of road infrastructure on protected wildlife species—particularly the brown bear and its habitats—in Western Macedonia, while supporting the conservation actions of the LIFE SAFE-CROSSING project.
To achieve these objectives, the project:
-Produced a mini-documentary, based on the scientific findings of the LIFE SAFE-CROSSING and LIFE AMYBEAR projects, to raise public awareness about the impacts of wildlife–vehicle collisions on biodiversity.
-Developed RoadCoex, an innovative mobile application for smartphones and tablets featuring interactive educational content and gamification elements designed to encourage users to explore wildlife-friendly road safety practices.
-Organised participatory workshops in collaboration with civil society organisations and informal citizen groups to record local attitudes and engage residents of Western Macedonia in efforts to reduce threats to wildlife, particularly the brown bear.
-Carried out field activities to support the implementation of conservation measures developed within the LIFE SAFE-CROSSING project.
The RoadCoex mobile application is available on Google Play & App Store
You can also watch the project’s mini-documentary online here.
Callisto served as an environmental advisor to Egnatia Odos S.A. throughout the implementation of this 18-month programme, which was completed in February 2009.
Key achievements for brown bear conservation
The programme significantly improved both the overall design of the motorway and the technical specifications of wildlife crossing structures along the relevant sections of the Egnatia Motorway. These improvements built upon an earlier, major redesign of the project that followed legal action by environmental NGOs before the Council of State and the subsequent revision of the project’s environmental terms.
The monitoring programme achieved the following:
-Increased the width of the only green bridge (wildlife overpass) on the Panagia–Grevena (Section 4.1) motorway segment from 30 m to 50 m.
Added two additional wildlife underpasses.
-Improved the dimensions and openness of several box culverts, making them more suitable and attractive as wildlife underpasses.
-Replaced the original roadside fencing with reinforced wildlife exclusion fencing built to improved technical specifications.
-Secured the cancellation of a planned toll station and motorway service area within the ecologically sensitive Section 4.1.
-Ensured compliance with environmental requirements regarding the management of hazardous waste during the motorway construction phase.
Callisto also coordinated the two-year project “Monitoring and Assessment of the Impacts of the Construction and Operation of the Egnatia Motorway on Large Mammals and Their Habitats in the Panagia–Grevena Section (Section 4.1)”. As part of this work, the organisation was responsible for monitoring the impacts of motorway construction on large carnivores, particularly the brown bear and the grey wolf. The construction-phase monitoring programme was completed in March 2009.
This study was commissioned to Callisto in August 2007 under the Technical Assistance Measure of the Operational Programme “Environment 2000–2006” (EPPER III). The project was completed in November 2008.
Key achievements
The study has become an important reference framework for the adoption of best-practice standards for the implementation of wildlife mitigation and compensation measures in transport infrastructure projects.
Its recommendations support the planning and construction of roads and other transport infrastructure, particularly in areas of high ecological value that provide habitat for important wildlife species, especially large mammals. The primary objective is to reduce habitat fragmentation, maintain ecological connectivity, and safeguard the long-term viability of wildlife populations by integrating effective mitigation measures into infrastructure design and managemen