The available data on the sizes of tropical tunas caught by the different fisheries are presented as: Available size frequency data: The size frequency data available in the IOTC databases is presented in FL_YFT.xlsx (20-09-2013), FL_BET_rev1.xlsx (25-09-2013) and FL_SKJ.xlsx (20-09-2013). All size data strata not recorded as fork length was converted into fork length by using the equations in Equations.pdf. Fish recorded under size classes other than those used for tropical tuna species was assigned to the corresponding size class/es for each species (first class is 10cm for all tropical tunas and class interval is 2cm for yellowfin tuna and bigeye tuna and 1cm for the skipjack tuna). Details about the amount of data available to create the above files can be found in SF_reference.xlsx.