Using fishery-dependent data to inform the development and operation of a co-management initiative to reduce cod mortality and cut discards

  • Published source details Holmes S.J., Bailey N., Campbell N., Catarino R., Barratt K., Gibb A. & Fernandes P.G. (2011) Using fishery-dependent data to inform the development and operation of a co-management initiative to reduce cod mortality and cut discards. ICES Journal of Marine Science, 68, 1679-1688.


This study is summarised as evidence for the following.

Action Category

Establish temporary fishery closures

Action Link
Marine Fish Conservation
  1. Establish temporary fishery closures

    A replicated, controlled, before-and-after study in 2008–2009 of a large bottom fished area in the North Sea, off northeast Scotland, UK (Holmes et al. 2011) found that fixed temporary seasonal area closures had little effect on reducing fishing effort for Atlantic cod Gadus morhua during implementation, but real-time area closures reduced overall cod landings and discards. A reduction in the number of vessels operating within the fixed closure areas (45–69 days) was found in only one of three areas, compared to the 14 days before closure (during: 3 vessels, before: 8 vessels) and was lowest in the 14 days after closure (1 vessel), while for the other two closure areas, vessel activity was similar (during: 2–4 vessels, before: 3–4 vessels, after: 1 vessels). A fourth area closed initially for four months (1 December 2008 to 31 March 2009) was kept closed for at least a year because test catch rates of cod exceeded the threshold set for re-opening. In addition, separate real-time closures implemented in 2009 resulted in estimated overall annual reductions in cod catch (landings and discards) of 707 t. Seasonal (total of four) and real-time (maximum of 12 at any one time, closed for 21 days when cod catch rate threshold exceeded) closures were implemented for Scottish vessels in 2008 and 2009 to control fishing effort and reduce mortality and discarding of cod (activity by non-Scottish vessels not required to adhere to closures was recorded). Data were collected in 2008–2009 from landings and monitoring systems of vessels fishing in and around the closure areas.

    (Summarised by: Chris Barrett)

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