Determination of Catch Efficiency and Length Composition of Anchovy (Engraulis Encrasicolus L., 1758) Caught by Midwater Trawl During Night in the Black Sea

Abstract

The aim of this study is to determine catch amount and size composition of anchovy in pelagic trawl along night time that carried out at fishing season 2005-2006 in Black sea. Night time was divided 3 periods as 17:00-20:00, 21:00-00:00 and 01:00-04:00, and was performed 6 tows for each period. Total 138 180 kg fish was fishing along study, I. period II. period and III. period 34 560 kg, 66 360 and 37 260 kg respectively. Mean size of all fishes caught 10,19 +/- 0,03 cm were determined, I. II. and III. period 10,26 +/- 0.05 cm; 9,89 +/- 0,04 cm and 10,42 +/- 0,09 cm respectively. Difference between Catch efficiency and mean size for fishing operation was done at different time periods was significantly (p<0,05). Change of school structure and movements showed in anchovy fishing by midwater trawl and depend on that be variation especially in catch efficiency and size composition were determined. Besides although decreasing of catch efficiency is at sun set and dawn due to there is less saturation on the net, more size fishes as to midnight fishing in these periods could be saying.