Reproductive biology of the black-striped pipefish Syngnathus abaster Risso, 1827 (Pisces: Syngnathidae) in the Aegean Sea of Turkey

The paper presents the results of research on the reproductive biology of Syngnathus abaster - a species distributed in Candarli Bay. For this purpose, seine nets were collected from a depth of 0.5-2 m in 15 minute periods between April 2013 and March 2014, and a total of 185 individuals were sampled. It has been determined that 94 individuals (50.81%) were females, 79 were males (42.70%) and 12 were immature (6.49%). The sex ratio was 1: 0.84. The average length values in female, male and immature individuals were 111.5 +/- 7.35, 109.9 +/- 11.08 and 79.8 +/- 5.30 mm, respectively. The maximum mean surface water temperature is in spring and summer seasons. When Gonadosomatic Index (GSI%) values were examined, the spawning period of the species was indicated as spring and summer. Three groups of species were identified as maturing (diameter: 0.61-1.20 mm), mature (diameter: 1.21-1.70 mm) and hydrated oocytes (diameter: 1.71-2.10 mm) in ovaries of female individuals. The number of eggs in the brood pouch of pregnant male fishes was on average 48 (mean +/- SD = 48 +/- 14.09 eggs, range: 23-78 eggs). The hydrated oocyte/total length relationship was: y = 0.8651x - 84.332 (n = 14, r(2) = 0.64) and the number of eggs/total length relationship in the brood pouch of pregnant males was: y = 1.0168x - 67.715 (n = 33, r(2) = 0.58).