Implementation of CMSY method for estimating fisheries reference points in Turkish stocks


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DEMİREL N.

ASLO 2017 Aquatic Sciences Meeting, Hawaii, United States Of America, 26 February - 03 March 2017, pp.66

  • Publication Type: Conference Paper / Summary Text
  • City: Hawaii
  • Country: United States Of America
  • Page Numbers: pp.66

Abstract

The aim of ecosystem-based fisheries management is to provide the maximum sustainable take of target organisms with the minimum impact on other ecosystem components. The main challenge of the approach is that in the developing countries, including Turkey, stock assessments have been made only for a tiny minority of stocks with the rest of these being categorized as “data poor stocks”.Based on this motivation, we will focus on the question: Can we successfully develop an ecosystem based management scheme for the data-poor fish stocks of Turkey? Surplus production modeling was used to estimate fisheries reference points in a maximum sustainable yield (MSY) framework. Fishing pressure and biomass were estimated from 2000 to 2015. Results are presented by region and by main functional groups (benthic fish & invertebrates, small pelagics, benthopelagics, large predators). Cumulative biomass of exploited species was well below the MSY-level in allregions. Large predators have low biomass and were subject to strong overfishing in all regions. In the last year with available data, 60% of the stocks were subject to ongoing overfishing and 60% of the stocks were outside of safe biological limits, potentially suffering from impaired reproduction. Only 8% of the stocks fulfilled the requirement of the Common Fisheries Policy of Europe as being not subject to overfishing and having a biomass above the level that can produce maximum sustainable yields. After rebuilding of the stocks and assuming a precautionary target of 90% of the maximum sustainable yield, an increase of about 60% over current catches could be possible.