Overview

Building on two decades applying good practice in all the steps of the transport infrastructure life cycle, a wide number of solutions or mitigation measures can be applied to reduce the negative effects of infrastructure (see Chapter 1 – Ecological effects of infrastructure) and benefit biodiversity and societies. Currently, innovative practices and new technologies are being developed to provide appropriate answers to emerging trends and new scenarios that arise from global change. More importantly, these solutions should provide appropriate response to the achievement of the objectives of the European Green Deal and particularly of the EU Biodiversity Strategy for 2030.

Main messages

• Solutions to be applied by the transport sector include measures to reduce the impact of traffic on wildlife populations and the negative effects associated to habitat fragmentation, particularly wildlife mortality and barrier effect. Moreover, preservation and restoration of ecosystems and ecological connectivity are crucial goals for mitigation measures.
• Mitigation measures must be developed following the mitigation hierarchy (Avoid – Reduce – Compensate) (see Chapter 3 – The mitigation hierarchy). It also must be implemented and accurately integrated along all the life cycle phases (see Chapter 2 – Policy, strategy and planning): Strategic Planning, Design, Construction, Operation/Maintenance and in the Upgrade/Adaptation processes. As a general rule, early stages of the infrastructure development provide more opportunities to avoid negative effects than latter stages.
• Location of the measures is a critical decision which determines success or failure. Accurate analyses to define in which places provide best benefits-cost balance are an essential step of the mitigation design. 
• Mitigation measures can provide solutions to multiple conflicts and challenges if they are appropriately designed. For example, a measure to reduce wildlife mortality, such as a wildlife passage combined with fencing, could also contribute to restore ecological connectivity.
• Benefits for people can also be achieved in terms of reduction of traffic accidents but also by combining wildlife and human uses in the crossing structures. Conversely, negative consequences of the application of the mitigation measures should be carefully analysed and avoided.
• Habitats related to transport infrastructure (e.g. verges and drainages) can be adapted to provide refuges or food for wildlife. Nevertheless, attraction of fauna to areas where can cause conflicts or suffer a high risk of mortality must be avoided.

Actions to take

• Use mitigation measures to minimise the risk of wildlife mortality as well as to increase infrastructure safety and functionality. Examples include: reducing wildlife-risk events such as animal-vehicle collisions, animal droughts in waterways, bird strikes in airports, bird collisions or electrocution with railways catenaries, powerlines or wind miles, bird collisions with glasses and transparent screens, or animals being trapped in any parts of infrastructure. 
• Maintain and/or restore ecological connectivity across infrastructure, allowing animal movement and providing safe crossing points areas of the infrastructure. This will reduce infrastructure barrier effect and help to restore ecosystems, particularly in ecological corridors connecting protected areas. Such actions will contribute to long-term persistence of wildlife populations and to climate change adaptation. 
• Apply nature-based solutions to drainage systems, verges and other green areas maintenance helping to reduce the climate risk events, which cause negative impact for infrastructure but also to surrounding habitats and urbanised areas (e.g. floods, forest fires, or erosion).
• Implement early-awareness and control measures to prevent the spread of Invasive Alien Species (IAS), which may threaten native habitats and species, pose problems to infrastructure maintenance, and even increase health risks to people.
• Benefit species which provide essential ecosystem services and particularly, contribute to the recovery of pollinators by applying appropriate maintenance to green and blue areas associated to transport infrastructure.
• Reduce the use of pesticides and fertilizers and minimise noise and light pollution allowing to improve both, quality of habitats for wildlife and human health.