This paper presents a brief review of the present state of knowledge in stock–recruitment forecasting, including process and current methodological challenges to predicting stock–recruitment. The discussion covers the apparent inability of models to accurately forecast recruitment even when environmental covariates are included as explanatory variables. The review shows that despite the incremental success in the past hundred years, substantial challenges remain if the process of modelling and forecasting stock–recruitment is to become relevant to fisheries science and management in the next 100 years.

Arctic and Antarctic marine systems have in common high latitudes, large seasonal changes in light levels, cold air and sea temperatures, and sea ice. In other ways, however, they are strikingly different, including their: age, extent, geological structure, ice stability, and foodweb structure. Both regions contain very rapidly warming areas and climate impacts have been reported, as have dramatic future projections. However, the combined effects of a changing climate on oceanographic processes and foodweb dynamics are likely to influence their future fisheries in very different ways. Differences in the life-history strategies of the key zooplankton species (Antarctic krill in the Southern Ocean and Calanus copepods in the Arctic) will likely affect future productivity of fishery species and fisheries. To explore future scenarios for each region, this paper: (i) considers differing characteristics (including geographic, physical, and biological) that define polar marine ecosystems and reviews known and projected impacts of climate change on key zooplankton species that may impact fished species; (ii) summarizes existing fishery resources; (iii) synthesizes this information to generate future scenarios for fisheries; and (iv) considers the implications for future fisheries management. Published studies suggest that if an increase in open water during summer in Arctic and Subarctic seas results in increased primary and secondary production, biomass may increase for some important commercial fish stocks and new mixes of species may become targeted. In contrast, published studies suggest that in the Southern Ocean the potential for existing species to adapt is mixed and that the potential for the invasion of large and highly productive pelagic finfish species appears low. Thus, future Southern Ocean fisheries may largely be dependent on existing species. It is clear from this review that new management approaches will be needed that account for the changing dynamics in these regions under climate change.

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Vølstad, J. H., Korsbrekke, K., Nedreaas, K. H., Nilsen, M., Nilsson, G. N., Pennington, M., Subbey, S., and Wienerroither, R. 2011. Probability-based surveying using self-sampling to estimate catch and effort in Norway's coastal tourist fishery. – ICES Journal of Marine Science, 68: 1785–1791. Recreational fishing as a tourist activity has become an increasingly important part of the Norwegian travel industry and may contribute significantly to the fishing mortality on Norwegian coastal cod (Gadus morhua). Quantifying catches in the tourist fishery is made difficult by Norway's intricate and long coastline, and the lack of a fishing licence system, a registry of businesses catering for fishing tourists, and a registry of charter boats. A probability-based survey was used to estimate annual catch and effort by boat for anglers associated with 445 tourist-fishing businesses during 2009. From a stratified random sample of businesses, fishing tourists were recruited systematically over time to record their daily catch and effort in diaries. Cod dominated the reported landed catch (harvest) north of 62°N, and saithe and mackerel dominated south of 62°N. The estimated total landed catch of all species taken by tourist fishers in the business sector during 2009 was 3335 t (relative standard error, RSE = 17%), of which 1613 t (RSE = 22%) were cod. It is concluded that surveys based on self-sampling can yield accurate estimates of catch and effort accounted for by the business sector of the Norwegian tourist fishery and that the tourist catch of coastal cod is insignificant compared with the commercial and recreational catch by local residents.

The Northeast Arctic cod (Gadus morhua L.: NEAC) remains the most abundant cod stock in the North Atlantic, while the catches of the partially co-occurring Norwegian coastal cod (NCC) stocks have dramatically decreased in recent years. To ensure effective management of the two stocks, it is necessary to know if the population genetic structure is associated with any pattern in the spatial dynamics or whether it is affected by any distinct environmental factors. By combining information from electronic data storage tags (DST) and molecular genetics methods with statistical tools, we have been able to associate spatial dynamics and distinct environmental factors to the two cod stocks. In general, adult NEAC migrate between deep, warm overwintering grounds and shallow summer feeding grounds where water temperatures maybe low. In contrast, NCC do not undertake large-scale seasonal migrations, show little seasonal variation in depth distribution, and experience the opposite seasonal change in temperature compared with NEAC. However, within the NCC group, some individuals did conduct longer horizontal movements than others. Even though the distances calculated in this study represent the shortest distance between release and recapture positions, they are far higher than previously reported by NCC. Distinctive depth profiles indicate that this migrant NCC have moved out of the area, passing the deep trenches outside Lofoten while more stationary NCC occupies shallower depths throughout the year. The temperature profiles also indicate that migrant and stationary NCC has occupied different areas during the year. We demonstrate that the combination of information from DSTs and molecular genetics offers a deeper understanding of individual cod behaviour, provides an insight in the spatial dynamics of the species, and ultimately, improves the scientific basis for management of a complex mixed fishery of Atlantic cod.