The development of sustainable transport is a key challenge in societies where there is an accelerated need for socio-economic development. This is the case for seven countries from central and south-eastern Europe that share the Carpathian Mountains. The challenge of developing sustainable transport requires transdisciplinary, or at least cross-sectoral cooperation, between the transport development and nature conservation sectors. Such cooperation is not in the culture of the Carpathian countries, which together host some of the most remarkable biodiversity values in Europe, including the largest populations of brown bear, grey wolf and Eurasian lynx. The overall length of motorways in these countries more than quintupled in the last 30 years and the rapid expansion of Linear Transport Infrastructure (LTI) continues at exacerbating rates. The rich biodiversity habitats are being fragmented and the concept of ecological connectivity is poorly understood and implemented by the national authorities. Ecological networks for large carnivores are not defined nor officially recognised in the Carpathian countries, with little exceptions. The legislation is not consistent across the strands of ecological connectivity and is not harmonised between the countries to effectively support transnational conservation efforts. Thus, the critical intersections between planned or even existing LTI and ecological corridors for large carnivores cannot be identified, in most cases leading to increasing habitat fragmentation and isolation of wildlife populations in the region. We summarised all this key context-related information for the Carpathians in relation to LTI development and ecological connectivity. To counteract this trend in the Carpathian ecoregion, we propose a set of recommendations to: improve and harmonise the legislation; develop and endorse methodologies for designating ecological corridors; address the cumulative impact on ecological connectivity; define other threats on landscape permeability; improve stakeholder engagement, cooperation and communication; develop comprehensive and transparent biodiversity and transport databases; monitor wildlife and transport for implementing most appropriate mitigation measures and strategies; build capacity to address the issue of sustainable transportation; and foster transnational cooperation and dialogue. Bringing these elements together will support the design of ecological networks in a way that considers the needs and location of both current and future habitats and contribute to efforts to address the climate crisis. These specific recommendations are relevant also for other areas of the world facing similar problems as the Carpathians.
