From experiment to intervention: a case study of scaling up marine eco-engineering from research to application

Ecosystems globally are becoming increasingly degraded necessitating conservation and repair. Alongside restoration of natural habitats, eco-engineering can mitigate the negative impacts of urban seascapes by co-designing marine-built structures for nature as well as humans. The application of eco-engineering to marine built structures is supported by over two decades of research demonstrating the efficacy of this approach in enhancing biodiversity but there remain few examples of interventions moving beyond experimental- to large-scale (10–100 s m) and long-term (decadal) implementation. Using lessons learned from eco-engineering research in Sydney Harbour, Australia, we outline six key steps that facilitate moving from experimental to larger scale retrofitted eco-engineering interventions. These are: (1) identifying the ecological problem and the most tractable solutions; (2) engaging with stakeholders, (3) obtaining approvals, (4) establishing demonstration sites that illustrate to stakeholders the practicality and benefits of the solution, (5) building an evidence base for efficacy of the solution, and (6) scaling up supply. Our framework draws on learnings from the Living Seawalls project, and on the extensive small-scale experimentation that led to it. Living Seawalls is an eco-engineering initiative that grew out of Sydney Harbour and has now been applied to sites across Australia and globally. Our framework also draws on learnings from other existing projects (e.g. Ecostructure, Blue Cube) and frameworks (e.g. Greening the Grey, International Guidelines on Natural and Nature-Based Features for Flood Risk Management) developed elsewhere. This work provides a template by which scientists can work with policy makers, managers, and other stakeholders to effect positive environmental change.