Case study 1 - Directed single species fisheries

This case studies includes three sub-components:

  • Fishery for highly vulnerable stock: orange roughy in Namibian waters – Coordinator: NatMIRC (Namibia) 
  • Fishery for highly vulnerable stock: orange roughy in ICES VI &VII – Coordinator: Marine Institute (Ireland) 
  • Fishery for less vulnerable stock: blue ling ( Molva dypterygia) in Vb,VI ,VII – Coordinator: Cefas (UK) 

Abstract :
Orange roughy in Namibian waters is be led by the National Marine and Information Research Centre (NatMIRC) in Swakopmund, Namibia. In Namibia orange roughy started off as an exploratory fishery in the mid 1990s with catches of about 6 000 tonnes by the end of 1995. In 1997, orange roughy became a quota managed fishery with an initial allocated TAC of 12 000 tonnes. The observed biomass has since decreased substantially and catch rates have declined.
Orange roughy in ICES VI and VII is led by Marine Institute, Ireland. In the nineties a series of deep-water surveys were carried out to investigate the abundance, distribution and biological aspects of deep-water fisheries in the waters west of Ireland. In 2003 the MI commissioned a national study into the assessment of orange roughy stocks west of Ireland using acoustic techniques, while currently an annual deep-water survey programme is carried out to obtain abundance indices and biological information of deep-water stocks.
Cefas is responsible for the blue ling sub-component of the Case Study with assistance from several other partners. Blue ling is typical gadoid species insofar as it is not particularly slow-growing or long-lived, however, historically fisheries have targeted spawning aggregations and this species can be vulnerable to fishing. The southern blue ling stock is now seriously depleted (ICES, 2006). Notwithstanding, it is a useful example of a stock that could respond relatively quickly (compared to more slow-growing, longer lived deep-water species) to improvements in the existing management and monitoring framework. This blue ling stock is currently fished mainly by the French trawl fishery for mixed deep-water species and therefore provides management and monitoring challenges in the context of a multi-species fishery.