Abstract
This study was conducted to determine the optimum temperature and salinity for the hatching rate, hatching time of eggs and larval activity of Farfantepenaeus aztecus (Ives, 1891). For this purpose, F. aztecus, which was caught from nature in the 4th gonad stage and were spawned on the same night in controlled laboratory conditions. The eggs were stocked in 2-l round bottom glass flasks and received one of nine temperature (24, 28 and 32°C) and salinity (30, 35 and 40 ppt) combinations as 50 eggs per liter after determining the fertility rate of the eggs. Although eggs hatched in all salinity and temperature combinations, water temperature, salinity and interaction had significant effects on hatching rate, hatching time and larval activity (P<0.05). Considering only salinity, the best hatching ratio was found at 35 ppt (48.44%), 40 ppt (47.89%) and the lowest hatching rate was found at 30 ppt (34.77%, P<0.05). It was found that the best hatching ratios were at 28°C (52.22%), at 32°C (48.33%) and followed by the eggs incubated 24°C (30.55%, P<0.05). The incubation time was shortened due to the increase in water temperature and changed between 11.40-17.10 hours. It was determined that the activities of the larvae incubated at lowest water temperature (24°C) and at 30 ppt were weaker than those incubated at 28°C and 35- 40 ppt salinities. The results show that 28-32°C water temperature and sea salinity slightly less than the salinity of the Mediterranean Sea (38.5 ppt) are optimal for the incubation eggs and for the production of high quality nauplii of F. aztecus found in the Northeastern Mediterranean.
Thanks
This article is part of the first author's master thesis. The authors thank Dr. Yavuz Mazlum for his data analysis and valuable suggestions for this manuscript.