Paul J. Dolder

Effort reduction and the large fish indicator: spatial trends reveal positive impacts of recent European fleet reduction schemes

© Foundation for Environmental Conservation 2015. The online version of this article is published within an Open Access environment subject to the conditions of the Creative Commons Attribution licence http://creativecommons.org/licenses/by/3.0/ doi:10.1017/S0376892915000077 Effort reduction and the large fish indicator: spatial trends reveal positive impacts of recent European fleet reduction schemes

Achieving maximum sustainable yield in mixed fisheries: a management approach for the North Sea demersal fisheries

Achieving single species maximum sustainable yield (MSY) in complex and dynamic fisheries targeting multiple species (mixed fisheries) is challenging because achieving the objective for one species may mean missing the objective for another. The North Sea mixed fisheries are a representative example of an issue that is generic across most demersal fisheries worldwide, with the diversity of species and fisheries inducing numerous biological and technical interactions. Building on a rich knowledge base for the understanding and quantification of these interactions, new approaches have emerged. Recent paths towards operationalizing MSY at the regional scale have suggested the expansion of the concept into a desirable area of “pretty good yield”, implemented through a range around FMSY that would allow for more flexibility in management targets. This article investigates the potential of FMSY ranges to combine long-term single-stock targets with flexible, short-term, mixed-fisheries management requirements applied to the main North Sea demersal stocks. It is shown that sustained fishing at the upper bound of the range may lead to unacceptable risks when technical interactions occur. An objective method is suggested that provides an optimal set of fishing mortality within the range, minimizing the risk of total allowable catch mismatches among stocks captured within mixed fisheries, and addressing explicitly the trade-offs between the most and least productive stocks.

Risks and benefits of catching pretty good yield in multispecies mixed fisheries

Risks and benefits of catching pretty good yield in multispecies mixed fisheries Robert B. Thorpe*, Simon Jennings, and Paul J. Dolder Lowestoft Laboratory, Department of Fisheries, Centre for Environment, Fisheries and Aquaculture Science (CEFAS), Pakefield Road, Lowestoft NR33 0HT, UK School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK *Corresponding author: tel: þ44 1502 524555; fax: þ44 1502 513865; e-mail: robert.thorpe@cefas.co.uk. Present address: International Council for the Exploration of the Sea, H.C. Andersens Boulevard 44–46, 1553 Copenhagen V, Denmark Thorpe, R. B., Jennings, S., and Dolder, P. J. Risks and benefits of catching pretty good yield in multispecies mixed fisheries. – ICES Journal of Marine Science, 74: 2097–2106.