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The following datasets are available for download. Please let us know if you encounter any problems in accessing the data. These datasets have been submitted to several validation procedures at the Secretariat. However, the procedures might not be exhaustive enough to uncover all potential problems. If you discover any major inconsistency in the data, please let us know as soon as possible. Click here to download a Microsoft word version of the text below.
Data Catalogues (to be released):
The file CAT_ALB08.pdf (to be released), contains information on the amount of nominal catches strata for which catch and effort and/or size frequency data are available for albacore (Catalogues on Data Availability for albacore).
Nominal Catches (available):
Total catch estimates per Fleet, Year, Gear, IOTC Area and species. The catches not reported per species or gear were assigned to the corresponding gears and/or species by the Secretariat.
The catches estimated for 1950-2007 and details about the data source and data quality can be found in the spreadsheet:
NC_ALB.xls (as of 3-9-2008) (compressed with WinZip)
Catches and Effort (available):
Catch and effort data (as of 3-9-2008) are presented as three different files:
• vessels using drifting longlines — CELL.txt
• vessels using pole and lines or purse seines — CEPSBB.txt
• vessels using gears other than those referred to above — CEOTHR.txt
Or click here if you want to download the above three files in one go CEDATA.zip
Catches (in tonnes or/and in number) and effort are recorded per Fleet, Year, Gear, Type of School, Time Interval (month or quarter usually), grid (usually 1 degree square areas for surface gears and 5 degrees square areas for longlines) and species.
Catches and effort are not available for all Nominal catches strata. When recorded, the catches in these datasets might represent the total catches of the species in the year for the fleet and gear concerned or represent simply a sample of those.
More details about the catch and effort information available and the way in which the above text files might be read can be found in CE_Reference.xls
Raised catches per area for bigeye tuna, yellowfin tuna, skipjack tuna, albacore and swordfish (available):
The Secretariat estimated catches of bigeye tuna, yellowfin tuna, skipjack tuna albacore and swordfish per gear, (School type), year, quarter and 5 degrees square grid from the available nominal catches. These can be found in C_BIG5_raised.csv (as of 22-09-2008)(compressed with WinZip)
Size frequency data (available):
The available data on the sizes of albacore caught by the different fisheries are presented as:
Non-raised size frequency data: The size frequency data available in the IOTC databases is presented in FL_ALB.csv (as of 29-09-2008) , All size data strata not recorded as fork length was converted into fork length by using the equations available for each species. Fish recorded under size classes other than those used for albacore was assigned to the corresponding size class/es for each species (first class is 10cm and class interval is 1cm).
Raised size frequency data or Catch-at-Size data: The available size data for albacore was raised to the total catches recorded for the species. The results of this process are presented as:
The estimated size frequency data are presented in CAS_TablesALB.xls (as of 29-09-2008). This spreadsheet contains also information on the amount of data substitution required, average weights estimated from the estimated data and other information.
Equations: The equations used to estimate standard lengths from non-standard measurements and to estimate weight from the available lengths can be found in ConvFLW.doc (as of 22-9-2008)
Details about the amount of data available to create the above files can be found in SFreference.xls (compressed with WinZip).
Catch-at-Age Data (available):
The available catch-at-size data for albacore was used to estimate catch-at-age.
CAA in aggregated format are presented in CAA_TableALB.xls (slicing Lian-Kang Lee, Shean-Ya Yeh, south Atlantic albacore spines, as of 7-10-2008).
For further information:
Please, do not hesitate to contacting the IOTC Secretariat ( mh@iotc.org or data.assistant@iotc.org ) if you have any question regarding these datasets |