The JRC MEDITS R script

Abstract

Main fishery stock assessment methods needs not only fishery dependent information but also fishery independet information which are, in almost all the cases, derived from scientific surveys at sea. In the Mediterranean Sea the main fishery independet information come from the Mediterranean International Trawl Survey (MEDITS) carried out since 1994. Primary Medits data such as, haul information, catches in weight and number by hauls and biological data of target species are routinely collected and stored in dedicated files. These file are made available to the STECF EWG stock assessment meetings through an official Data Call launched by DGMare. This tool developed as an R script gives the opportunity, starting from these files, to compute standardized biomass and density indexes and length frequency distributions, checks hauls positions and other main hauls characteristics and many other useful outputs.