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Climate change is shifting the abundance and distribution of marine species with consequences for ecosystem functioning, seafood supply, management and conservation. Several approaches for future projection exist but these have never been compared systematically to assess their variability. We conducted standardized ensemble projections including 6 global fisheries and marine ecosystem models, forced with 2 Earth-system models and 4 emission scenarios in a fished and unfished ocean, to derive average trends and associated uncertainties. Without fishing, mean global animal biomass decreased by 5% (±4%) under low and 17% (±11%) under high emissions by 2100, primarily driven by increasing temperature and decreasing primary production. These climate-change effects were slightly weaker for larger animals and in a fished ocean. Considerable regional variation ranged from strong biomass increases in high latitudes to strong decreases in mid-low latitudes, with good model agreement on the direction of change but variable magnitude. Uncertainties due to differences among ecosystem or Earth-system models were similar, suggesting equal need for model improvement. Our ensemble projections provide the most comprehensive outlook on potential climate-driven ecological changes in the ocean to date. Realized future trends will largely depend on how fisheries and management adapt to these changes in a changing climate.

For future sustainable management of fisheries, we anticipate deeper and more diverse information will be needed. Future needs include not only biological data, but also information that can only come from fishers, such as real-time ‘early warning’ indicators of changes at sea, socio-economic data and fishing strategies. The fishing industry, in our experience, shows clear willingness to voluntarily contribute data and experiential knowledge, but there is little evidence that current institutional frameworks for science and management are receptive and equipped to accommodate such contributions. Current approaches to producing knowledge in support of fisheries management need critical re-evaluation, including the contributions that industry can make. Using examples from well-developed advisory systems in Europe, United States, Canada, Australia and New Zealand, we investigate evidence for three interrelated issues inhibiting systematic integration of voluntary industry contributions to science: (1) concerns about data quality; (2) beliefs about limitations in useability of unique fishers’ knowledge; and (3) perceptions about the impact of industry contributions on the integrity of science. We show that whilst these issues are real, they can be addressed. Entrenching effective science-industry research collaboration (SIRC) calls for action in three specific areas; (i) a move towards alternative modes of knowledge production; (ii) establishing appropriate quality assurance frameworks; and (iii) transitioning to facilitating governance structures. Attention must also be paid to the science-policy-stakeholder interface. Better definition of industry’s role in contributing to science will improve credibility and legitimacy of the scientific process, and of resulting management.

In two regions of British Columbia, small and medium-sized shoals of pre-spawning Pacific herring Clupea harengus pallasi were most numerous and occurred as neighbours more frequently than would be expected by chance. Herring displayed a typical diurnal vertical migration, although shoals in the Central Coast were more evenly distributed through the water column during the day than those in the Strait of Georgia. As maturation progressed, shoals were found in shallower water, more densely packed and vertically extended in shape. In the Strait of Georgia, shoals were considerably larger, and positioned relatively deeper in the water column. Very large (>5000 t) shoals were found at specific locations characterized by high water exchange. Large shoals may act as an anti-predator strategy to the abundant sealions and birds. Moreover, staying deep in the water column, and associating with dips in the sea bed, reduces predation risk and confers energy savings through hydrodynamic advantage. Smaller, denser, vertically extended, travelling shoals, prevalent during the later stages of gonad maturation, were similar in nature to labile spherical shoals observed in the Central Coast at different locations each day. Both these shoal types may benefit from synchrony and co-ordination when evading predators that is not possible for larger shoals. The more highly clustered distribution of shoals in the Central Coast is presumed to be linked to their tight association with rock outcroppings typical of this region. 1999 The Fisheries Society of the British Isles