Temporal change in UK marine communities: trends or regime shifts?

A regime shift is a large, sudden, and long-lasting change in the dynamics of an ecosystem, affecting multiple trophic levels. There are a growing number of papers that report regime shifts in marine ecosystems. However, the evidence for regime shifts is equivocal, because the methods used to detect them are not yet well developed. We have collated over 300 biological time series from seven marine regions around the UK, covering the ecosystem from phytoplankton to marine mammals. Each time series consists of annual measures of abundance for a single group of organisms over several decades. We summarised the data for each region using the first principal component, weighting either each time series or each biological component (e.g. plankton, fish, benthos) equally. We then searched for regime shifts using Rodionov’s regime shift detection (RSD) method, which found regime shifts in the first principal component for all seven marine regions. However, there are consistent temporal trends in the data for six of the seven regions. Such trends violate the assumptions of RSD. Thus, the regime shifts detected by RSD in six of the seven regions are likely to be artefacts caused by temporal trends. We are therefore developing more appropriate time series models for both single populations and whole communities that will explicitly model temporal trends and should increase our ability to detect true regime shift events.

Region-wide changes in marine ecosystem dynamics: state-space models to distinguish trends from step changes

Regime shifts are sudden changes in ecosystem structure that can be detected across several ecosystem components. The concept that regime shifts are common in marine ecosystems has gained popularity in recent years. Many studies have searched for the step-like changes in ecosystem state expected under a simple interpretation of this idea. However, other kinds of change, such as pervasive trends, have often been ignored. We assembled over 300 ecological time series from seven UK marine regions, covering two to three decades. We developed state-space models for the first principal component of the time series in each region, a common measure of ecosystem state. Our models allowed both trends and step changes, possibly in combination. We found trends in three of seven regions and step changes in two of seven regions. Gradual and sudden changes are therefore important trajectories to consider in marine ecosystems.

Marine and coastal policy in the UK: Challenges and opportunities in a new era

Marine and coastal policy in the UK has faced a number of significant changes in recent years, most notably the passing of the Marine and Coastal Access Act in 2009. These changes have brought significant challenges and opportunities for all those involved in the management and use of the UK's marine and coastal environment. This new era of marine policy inspired the UK's first Marine and Coastal Policy forum held in June 2011. In this introductory paper the global context of marine policy changes and the themes which emerged from the forum, forming the basis of the articles in this special issue, are outlined. It is concluded that there is a high level of engagement, capacity and willingness of key stakeholders to work collaboratively to address the environmental, social and economic complexities of managing the marine and coastal environment. It is both evident and encouraging that progress is being made and the many challenges faced in this new era give rise to a number of opportunities to develop new ideas and effective mechanisms for finding solutions

A comparison of the degree of implementation of marine biodiversity indicators by European countries in relation to the Marine Strategy Framework Directive (MSFD)

The degree of development and operability of the indicators for the Marine Strategy Framework Directive (MSFD) using Descriptor 1 (D1) Biological Diversity was assessed. To this end, an overview of the relevance and degree of operability of the underlying parameters across 20 European countries was compiled by analysing national directives, legislation, regulations, and publicly available reports. Marked differences were found between countries in the degree of ecological relevance as well as in the degree of implementation and operability of the parameters chosen to indicate biological diversity. The best scoring EU countries were France, Germany, Greece and Spain, while the worst scoring countries were Italy and Slovenia. No country achieved maximum scores for the implementation of MSFD D1. The non-EU countries Norway and Turkey score as highly as the top-scoring EU countries. On the positive side, the chosen parameters for D1 indicators were generally identified as being an ecologically relevant reflection of Biological Diversity. On the negative side however, less than half of the chosen parameters are currently operational. It appears that at a pan-European level, no consistent and harmonized approach currently exists for the description and assessment of marine biological diversity. The implementation of the MSFD Descriptor 1 for Europe as a whole can therefore at best be marked as moderately successful.

Marine and coastal policy in the UK: Challenges and opportunities in a new era

Marine and coastal policy in the UK has faced a number of significant changes in recent years, most notably the passing of the Marine and Coastal Access Act in 2009. These changes have brought significant challenges and opportunities for all those involved in the management and use of the UK's marine and coastal environment. This new era of marine policy inspired the UK's first Marine and Coastal Policy forum held in June 2011. In this introductory paper the global context of marine policy changes and the themes which emerged from the forum, forming the basis of the articles in this special issue, are outlined. It is concluded that there is a high level of engagement, capacity and willingness of key stakeholders to work collaboratively to address the environmental, social and economic complexities of managing the marine and coastal environment. It is both evident and encouraging that progress is being made and the many challenges faced in this new era give rise to a number of opportunities to develop new ideas and effective mechanisms for finding solutions.