Population Structure, Age, Growth and Reproduction Biology of Piper Gurnard, Trigla lyra (Linnaeus, 1758) in the Sea of Marmara, Turkey

This study describes the biomass, age, growth, mortality and reproduction biology of piper gurnard, Trigla lyra. Individuals were obtained with monthly trawl surveys between March 2017 and December 2018 from 34 stations located in the Sea of Marmara, Turkey. Mean Catch per unit effort (CPUE-kg/h) and stock amounts (biomass kg/km2) were calculated as 0,62 kg/h and 8,54 kg/km2, respectively. The age interval was determined as between I and VIII. Von Bertalanffy growth parameters were determined as L∞ = 59.92 cm, K = 0.21 per year and t0 = -0.36 for females and L∞ = 78.53 cm, K = 0.13 per year and t0 = -0.41 for males. The total mortality (Z) was determined as 0.55 t−1. The natural mortality (M) and fishing mortality (F) were estimated as 0.36 t−1 and 0.19 t−1. The exploitation rate was determined as 0.35 t−1. The length at first maturity (L50) was calculated as 32.7 cm TL for females and 25.2 cm TL for males. The spawning period of T.lyra was determined between December and April and peaked in March.