Regime shifts in the marine environment: The scientific basis and political context

► A comprehensive summary regime shifts on global and regional scales. ► Review of regime shift detection methods indicating advantages and drawbacks. ► Identification of gaps in policy initiatives with respect to biological regime shifts. ► Recommendations for long-term strategy in data collection, archival and analysis. ► Greater co-ordination and integration to exploit data and resources efficiently. Regime shifts in the marine environment have recently received much attention. To date, however, few large-scale meta-analyses have been carried out due to insufficient data coverage and integration between sustained observational datasets because of diverse methodologies used in data collection, recording and archival. Here we review the available data on regime shifts globally, followed by a review of current and planned policies with relevance to regime shifts. We then focus on the North and Baltic Seas, providing examples of existing efforts for data integration in the MarBEF Network of Excellence. Existing gaps in data coverage are identified, and the added value from meta-analyses of multiple datasets demonstrated using examples from the MarBEF integrated data project LargeNet. We discuss whether these efforts are addressing current policy needs and close with recommendations for future integrated data networks to increase our ability to understand, identify and predict recent and future regime shifts.