Reproductive biology of non-native Nemipterus randalli Russell, 1986 and native Pagellus erythrinus (Linnaeus, 1758) from the Aegean Sea

The present study examined reproduction biologies of 336 and 384 individuals of native Pagellus erythrinus and non-native Nemipterus randalli species captured using trammel nets in Marmaris Bay on a monthly basis from January to December 2018. Total length, weight and sex ratios in N. randalli obtained by trammel net were 9.2-21.2 cm (mean +/- SD; 16.2 +/- 2.43), 9.15-142.63 g (mean +/- SD; 61.23 +/- 29.12), 1:0.41, respectively. First maturity lengths for female and male individuals of N. randalli were 13.11 cm and 15.55 cm, respectively. Linear relationship between total length and fecundity of the species whose fecundity was 37785- 55200 (mean +/- SD; 46172 +/- 7450) was calculated as F=1445.1TL+34612 (R-2=0.75). For P. erythrinus species, total length and weight and sex ratios were 10.2-28.5 cm ( mean +/- SD; 18.50 +/- 3.37), 10.27-307.14 g (mean +/- SD; 88.53 +/- 48.57) and 1:0.64, respectively. The first maturity lengths of P. erythrinus were 12.69 cm in females and 14.83 cm in males, respectively. The fecundity of the species was found to be 34503-125102 eggs (mean +/- SD; 65863 +/- 25258). Linear relationship between total length and fecundity was F=10289TL-179 788 (R-2= 0.76).