Ecological forecasting in the presence of abrupt regime shifts

•We present a new multivariate climate predictor for the southern North Sea.•The North Sea Environmental (NSE) index allows prediction of macro zoobenthos in the presence of abrupt regime shifts.•The multivariate predictor has an excellent performance and a high versatility, better than single climate indices.•The concept presented here is in general applicable to all geographical regions in the world and all areas in marine biology.

Regime shifts may cause an intrinsic decrease in the potential predictability of marine ecosystems. In such cases, forecasts of biological variables fail. To improve prediction of long-term variability in environmental variables, we constructed a multivariate climate index and applied it to forecast ecological time series. The concept is demonstrated herein using climate and macrozoobenthos data from the southern North Sea. Special emphasis is given to the influence of selection of length of fitting period to the quality of forecast skill especially in the presence of regime shifts.Our results indicate that the performance of multivariate predictors in biological forecasts is much better than that of single large-scale climate indices, especially in the presence of regime shifts. The approach used to develop the index is generally applicable to all geographical regions in the world and to all areas of marine biology, from the species level up to biodiversity. Such forecasts are of vital interest for practical aspects of the sustainable management of marine ecosystems and the conservation of ecosystem goods and services.