Abstract

This study focuses on diel variability in bottom trawl catches of comber Serranus cabrilla (L., 1758) and brown comber Serranus hepatus (L., 1758). The fish samples were collected during a total of 7 24-hour bottom trawl surveys carried out within the same locality at the depths ranging from 50 to 58 m in Izmir Bay (the eastern Aegean Sea) in 2007–2008. In each seasonal survey 8 hauls with 20 minutes towing duration were performed in consecutive three hours intervals in order to cover an entire diel cycle of 24-hours. Some variations were observed in the percentage contributions of the two congeneric serranid fishes to the total catch by both sampling time and survey season. Their contribution to the total catches were sometimes high in dark period in some seasons and then low in some other seasons. In general, however, similar distribution patterns were observed for both species. Finally, no specific effect of «time of the day» factor on catch rates of the two serranid fishes was observed.