The Influence of the Moon Phase on the CPUEs of Swordfish Gillnet Fishery in the Aegean Sea, Turkey

This paper provides the analysis the moon phase's on CPUE (Catch per Unit Effort) related to Turkish Aegean swordfish (Xiphias gladius) gillnet fishery during 2009-2010 fishing seasons. Mean CPUE (kg/km) was 47.0 +/- 14.5 during the dark period, against 24.1 +/- 3.8 in light period in 2009. Besides, mean CPUE was 56.3 +/- 10.2 during the dark period, whereas 45.1 +/- 7.8 in light period in 2010. In the two years periods (2009-2010) examined, the mean CPUE was 50.5 +/- 9.7 during the dark period, while 32.8 +/- 4.1 in light period. All the CPUE peaks were clearly close to each new moon phase and the highest peak (300 kg/km) was computed in May 2009 during the dark period. The results obviously indicate the increasing of the swordfish landings during the dark periods.