On the conversion methodology of length composition of the Black Sea commercial fish, obtained by various ways of the fish length measuring and data consolidation
Applied in the Black Sea countries methods of length measurement for mass pelagic commercial fish species and the systems of these measurements unification in variational series are considered. Their considerable difference is marked to ba a significant obstacle for the formation of unified length composition arrays of commercial catches and their use with the aim of regional stock assessments with analytical methods. The approach to the development of the conversion methodology of length composition of the commercial fi sh species from one system of unified data into another one is proposed. The approach is based on the principle of factual redistribution of the measured fish in each length interval. Possibilities of electronic tables EXCEL were used for automatic converting of the sprat length composition.