Skilful decadal-scale prediction of fish habitat and distribution shifts

Abstract

Many fish and marine organisms are responding to our planets changing climate by shifting their distribution (i.e. where they are found). Such shifts can drive conflicts at the international scale and are highly problematic for the communities and businesses that depend on these living marine resources for income and nutrition. Advances in climate prediction mean that in some regions the state of the ocean, and thereby the drivers of these shifts, can be skilfully forecast up to a decade ahead. However, the potential for these forecasts to benefit ocean-dependent communities has yet to be realised. Here we show for the first time that marine climate predictions can be used to generate decadal-scale forecasts of shifts in the habitat and distribution of marine fish species, as exemplified by Atlantic mackerel, bluefin tuna and blue whiting. We show statistically significant forecast skill of individual years that outperform both persistence and climatological baseline forecasts for lead times of 3-10 years: multi-year averages perform even better, yielding correlation coefficients in excess of 0.90 in some cases. We also show that the habitat shifts underling recent conflicts over Atlantic mackerel fishing rights could have been foreseen on similar timescales. Our results show that climate predictions can be translated into information directly relevant to stakeholders and we anticipate that this tool will be critical in foreseeing, adapting to and coping with the challenges of a changing and variable future climate, particularly in the most ocean-dependent nations and communities.