SCIENTIFIC COMMITTEE FIFTH REGULAR SESSION 10-21 August 2009 Port Vila, Vanuatu An Alternative Estimate of Catches of Five Species of Sharks in the Western and Central Pacific Ocean based on Shark Fin Trade Data WCPFC-SC5-2005/EB-WP-02
نویسنده
چکیده
Conservation and Management Measure 2008‐06 was implemented by the Western and Central Pacific Fisheries Commission in February 2009 and requires the Commission to work toward providing preliminary advice on the stock status of key shark species in 2010. While the need for shark assessments is thus well‐recognised, catch data necessary to support such assessments is, in many cases, insufficient. Therefore, methods of assessing species for which no adequate historical catch time series exists should be explored. A method applied to the Atlantic Ocean by ICCAT, and presented here for the Western and Central Pacific Ocean, provides minimum estimates of shark removals using shark fin trade data. Because these estimates capture only a portion of the potential shark mortality, i.e. only those sharks’ whose fins are traded, the value of these estimates lies mainly in comparison to other WCPO records of total shark mortality in order to identify potential under‐reporting. There is reasonable agreement between SPC catch‐based estimates and the trade‐based estimates during the period of 1998‐2000 but after that time the median trade‐based estimates are up to two to three times higher than the catch‐based estimates. This result is similar to the result of a catch‐based versus trade‐based comparison for blue shark at ICCAT. Given that there are important uncertainties in both catch‐based and trade‐based estimates which cannot be resolved on the basis of existing data, further study of these and other methods is strongly encouraged.
منابع مشابه
SCIENTIFIC COMMITTEE NINTH REGULAR SESSION 6-14 August 2013 Pohnpei, Federated States of Micronesia Towards an Integrated Shark Conservation and Management Measure for the Western and Central Pacific Ocean WCPFC-SC9-2013/ EB-WP-08
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