Diurnal variations in CPUE and length composition of the catches in a Nephrops directed fishery in the Central North Sea
Redant, F.; De Clerck, R. (1984). Diurnal variations in CPUE and length composition of the catches in a Nephrops directed fishery in the Central North Sea. CM Documents - ICES, C.M. 1984(K:3). International Council for the Exploration of the Sea: Copenhagen. 9 + tables + figures pp. Part of: ICES CM Documents - ICES. ICES: Copenhagen. ISSN 1015-4744, more | |
Keywords | Biological phenomena > Biological rhythms > Circadian rhythms Dimensions > Length Nephrops Leach, 1814 [WoRMS] ANE, Belgium [Marine Regions]; ANE, North Sea [Marine Regions] Marine/Coastal |
Abstract | The report describes the Belgian Nephrops directed fishery in the Central North Sea (Botney Gut-Silver Pit area) and analyzes the diurnal variations in CPUE and catch composition of several commercial Nephrops trawlers operating in this area. Peak CPUE-values were generally obtained after dawn and before dusk. Some anomalies however did occur. These are discussed in relation to the natural variations in light intensity on the sea floor and the food requirements of Nephrops. There was no evidence of significant changes in the length composition of Nephros taken at different times of the day. The data even suggest that all size groups of Nephros respond in the same way to changes in light intensity. |
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