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

WORK PLANS FOR 2009− The estimation of age and growth parameters has been completed for white marlin. Work is in progress on anequivalent study of blue marlin, while new studies are just getting underway for sailfish and longbillspearfish.− A study on blue marlin reproduction off West Africa was completed, but similar work on sailfish in the samearea requires an additional year for completion.− A research project is underway to identify genetic biomarkers for Atlantic billfishes, with emphasis ondelineating the genetic stock structure of white marlin and roundscale spearfish. The project is supportedthrough international collaboration and facilitated by members of the ICCAT Billfish Species Group.− Research on vertical habitat of sailfish and white marlin expanded in 2008, whereas equivalent research onblue marlin was conducted in earlier years.− The review of billfish catches from artisanal fleets continued, especially in West Africa; however, a morerecent smaller initiative has started in the Caribbean with a study in the Dominican Republic.− New relative abundance indices for sailfish were obtained from several recreational, artisanal and longlinefleets. Several previously available sailfish indices were updated. A new index was obtained for West Africanblue marlin.− A review of Atlantic-wide sailfish catches was conducted, however, there is still a need to separate spearfishfrom some of the historical longline catches. To that extent, preliminary ratios of sailfish/spearfish have beendeveloped by 5 degree grid.Proposed work for 2009Work can be separated into two major programs, one aimed at preparing the next sailfish assessment, and theother at preparing for future blue marlin and white marlin assessments.In preparation for the 2009 sailfish assessment the following analyses are required:− Continue the collection and analysis of biological samples to study the age, growth and reproduction ofsailfish in Côte d’Ivoire.− Continue the efforts of reviewing catch estimates, especially for those countries that are known to landsailfish but do not report it to ICCAT.− The relative abundance indices of the following fleets need to be updated to provide estimates that include theyear 2007:- Japanese longline- Chinese Taipei longline− Analyses of data from the following artisanal fleets need to be initiated, or completed, to obtain new relativeabundance indices for all important artisanal fleets:- Côte d’Ivoire- Ghana- Sao Tomé and Principe− If possible, updates should be conducted for those indices presented before the 2009 sailfish assessment sothat they include data through year 2007. Additionally, a summary of all available size frequency data shouldbe provided for all fleets.− In order to prepare for an assessment of blue marlin and white marlin in 2011 the Working Group shouldprepare and plan for a marlin data preparatory meeting in 2010 that focuses on:- developing methods and data analyses that can facilitate the interpretation of historical longline CPUEindices;− accounting for under-reporting in the fleets that have been required to release marlins;- recovering and compiling statistics on marlin catches made by FAD fisheries from the Caribbean;- Use genetic analyses to review the reliability of species identification for marlins and spearfish, as reportedby the various fleets and observer programs;- Post-release survival of marlins.193