REPORT OF THE STANDING COMMITTEE ON RESEARCH ... - Iccat

ICCAT REPORT 2008-2009 (I)Catch and effort data and reporting deadlines. The deadline for submission of Task I and II data is July 31,2009.Combined biomass index. It is recommended that scientists from Japan, Canada, Portugal and the United Statescoordinate their work before the meeting (possibly using videoconference), with the goal of updating the indexprior to the start of the assessment. Action: National Scientists.Catch-at-size data. Catch at size is desirable to evaluate the effects of regulations. Catch at size should beavailable at the beginning of the meeting. Action: Secretariat.MediterraneanCatch and effort. All countries catching swordfish (directed or by-catch) should report catch, catch-at-size (bysex) and effort statistics by as small an area as possible (5-degree rectangles for longline, and 1-degree rectanglesfor other gears), and by month. It is recommended that at least the order of magnitude of unreported catches beestimated. The Group noted that it is important to collect size data together with the catch and effort data toprovide meaningful CPUEs. Although CPUE by age is the usual input for the age-structured analyses, the Grouprecognized that this must be based on an increased level of sampling, not merely substitution of the current data.Therefore, it is recommended that increased sampling take place so that CPUEs can be developed by age.Action: National Scientists.Age determination. Recent research work has indicated that estimates of age at length from direct ageing studiesvary within the Mediterranean on a geographic basis. To avoid the possibility that such variation results fromdifferences in age determination methods, national scientists were encouraged to exchange spine sections andshare age determination methodology. Action: National Scientists.Gear selectivity studies. Further research on gear design and use is encouraged in order to minimize catch of age-0 swordfish and increase yield and spawning biomass per recruit from this fishery. Action: National Scientists.Management. The Working Group recommends that future work should consider a broader set of managementscenarios including, apart from seasonal fishery closures, modifications of the fishing gears, fishing capacityreductions, minimum landing size regulations (MLS) and quota limitations. Economic aspects should be alsoconsidered. Action: National Scientists.SummaryBillfish Work PlanThe Working Group proposed to conduct the next assessment of sailfish in 2009.The Working Group is planning new assessments for blue marlin and white marlin in 2011, with a precedingdata preparatory meeting to be held in 2010. To achieve this, the Working Group needs to continue withdeveloping methods to better interpret the historical changes in billfish CPUE from longline data; and, thecontinued improvement of biological parameters, catch and relative abundance of marlins.BackgroundThe last stock assessments for blue marlin and white marlin were conducted in 2006. No assessments have everbeen conducted on spearfish. The last attempted assessment for sailfish (2001) was unable to estimate biologicalreference points such as maximum sustainable yield or the current state of the stock, mainly because of theuncertainty in the basic data required in the assessment. ICCAT has invested in billfish research for the purposeof improving the quality of data needed for stock assessments. However, additional information is still requiredto elucidate biological characteristics (e.g. defining essential habitat, survival, and growth), catch statistics(particularly for artisanal fisheries), and relative abundance indices.Work completed in 2008− A data preparatory meeting for the sailfish assessment was held in May 2008.192