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A new approach for estimating the fishing mortality benchmark F msy (fishing pressure that corresponds to maximum sustainable yield) is proposed. The approach includes density-dependent factors. The analysis considers 53 data-rich fish stocks in the Northeast Atlantic. The new F msy values are estimated from an ensemble of data sources: (i) applying traditional surplus production models on time-series of historic stock sizes, fishing mortalities, and catches from the current annual assessments; (ii) dynamic pool model (e.g. age-structured models) estimation for stocks where data on density-dependent growth, maturity, and mortality are available; (iii) extracts from multispecies and ecosystem literature for stocks where well-tested estimates are available; (iv) the "Great Experiment" where fishing pressure on the demersal stocks in the Northeast Atlantic slowly increased for half a century; and (v) linking F msy to life history parameters. The new F msy values are substantially higher (average equal to 0.38 year−1) than the current F msy values (average equal to 0.26 year−1) estimated in stock assessments and used by management, similar to the fishing pressure in the 1960s, and about 30% lower than the fishing pressure in 1970–2000. [ABSTRACT FROM AUTHOR]

Lassen, H., Pedersen, S. A., Frost, H., and Hoff. A. 2013. Fishery management advice with ecosystem considerations. – ICES Journal of Marine Science, 70: 471–479.The European Union Marine Strategy Framework Directive (MSFD) includes four descriptors of Good Environmental Status (GES) which are affected by fishing activity. These descriptors are: biodiversity, fish stocks, foodweb, and seabed integrity. This paper shows how these descriptors can be related to variables within an ecological model and how an ecological model can be used to analyse whether the fishing pressure that is estimated based on bioeconomic criteria is within general sustainable limits. The paper presents an example of such an analysis of the Eastern Baltic cod fishery using two models: a bioeconomic model and an ecological model. The models are calibrated based on historic data. The mapping between the descriptors specified by MSFD and variables available for analysis in the models is incomplete, e.g. genetics and spatial structures are not included in the models. The models can be used strategically, providing a qualitative understanding of the anticipated relative changes. [ABSTRACT FROM PUBLISHER]

Pedersen, S. A., Fock, H., Krause, J., Pusch, C., Sell, A. L., Böttcher, U., Rogers, S. I., Sköld, M., Skov, H., Podolska, M., Piet, G. J., and Rice, J. C. 2009. Natura 2000 sites and fisheries in German offshore waters.–ICES Journal of Marine Science, 66: 155–169. The principal objective of sites selected as part of Natura 2000 is to achieve or maintain a favourable conservation status of habitats and species named in the EU Birds and Habitats directives. In the German exclusive economic zone, the habitat types protected by this legislation are sandbanks and reefs; protected species include marine mammals, seabirds, and specific migratory fish species. The ICES project Environmentally Sound Fishery Management in Protected Areas (EMPAS) aims to answer two questions: (i) To what extent do specific fishing activities significantly threaten attainment of the conservation objectives of the Natura 2000 sites? (ii) What management measures would reduce these conflicts and how effective would they be at helping to ensure the favourable condition of these sites? Assessments of fishing impacts on Natura 2000 sites require basic data on the conservation status of individual habitats and species, as well as data for fine-scale distributions of ongoing fishing activities. This paper describes and discusses the process used by the EMPAS project in developing fishery-management plans for each Natura 2000 site in German offshore waters. [ABSTRACT FROM PUBLISHER]

A total of 1436 starry ray (Raja radiata) stomachs were collected on the shrimp fishing grounds off West Greenland in summer and autumn 1990–1991. Starry rays <20 cm fed primarily on copepods, gammarids, mysids, and polychaetes, while larger specimens >19 cm fed mainly on northern shrimp (Pandalus borealis but also fish, mainly redfish (Sebastes sp.)). The maximum sizes of shrimp and redfish eaten increased with ray size, but prey-predator size relationships showed weak correlations. Predator size, depth of water, and year were found to influence the average degree of stomach fullness. Starry ray is an opportunistic feeder. Northern shrimp and redfish are by far the most abundant shrimp and fish species on the West Greenland shrimp grounds and these prey species dominate the food of starry ray. Redfish becomes available to starry ray through fishing mortality in the shrimp fishery. [ABSTRACT FROM PUBLISHER]