Practitioner insights on challenges and options for advancing blue Nature-based Solutions.

The dual environmental crises of climate change and biodiversity loss pose severe threats to human health and well-being. Nature-based Solutions (NbS) are promoted as an important component of the response to simultaneously address both crises. However, their uptake in policy and planning has been impeded by evidence gaps and barriers to implementation, particularly in marine and coastal systems. Here, we describe practitioner perspectives on perceived challenges to implementing NbS in marine and coastal ecosystems (blue NbS) and make recommendations to overcome the most significant. These consensus perspectives were obtained through an exploratory, qualitative workshop, attended by environmental policy and practice stakeholders representing government and non-profit organisations from across Northern Europe, that identified and prioritised perceived challenges for in-depth discussion. Key priority challenges were: (1) policy driver and appropriate legislation to support NbS; (2) funding mechanisms; and (3) stakeholder awareness, values, and engagement. Discussions highlighted that successful implementation will require addressing these through better collaboration, communication, longer-term funding of projects, and better integration of top-down and bottom-up approaches to management. The strength, and at the same time difficulty, of NbS is that they draw together diverse actors and approaches, but improved standards are needed for application if they are to realise their potential. Ultimately, reducing uncertainty in the definition and concept of NbS amongst stakeholders is needed to accelerate their deployment in complex marine social-ecological systems. [Display omitted] • Nature-based Solutions (NbS) are important for responding to societal challenges. • Marine and coastal (blue) NbS implementation has lagged behind that on land. • We asked practitioners about perceived challenges to blue NbS implementation. • Key challenges included policy and legislation, funding and stakeholder engagement. • Recommend concept clarification, improved standards and better collaboration. [ABSTRACT FROM AUTHOR]