MARINE BIODIVERSITY, cilt.55, sa.6, 2025 (SCI-Expanded, Scopus)
This study presents novel insights into the population dynamics of the long-snouted seahorse (Hippocampus guttulatus) along the southeastern coast of the Black Sea. A total of 439 specimens (228 females and 211 males) were collected using a beam trawl (15 mm mesh size, 2 m width) across four depth zones (0-5, 5-10, 10-20, >= 20-30 m) at three stations (& Idot;yidere, Merkez, and & Ccedil;ayeli) between December 2012 and November 2013. The total length ranged from 6.6 to 11.4 cm in females and 7.0 to 13.5 cm in males, with mean lengths of 9.1 +/- 0.05 cm for both sexes. Strong correlations were observed in length-weight relationships (WLRs) for females, males, and combined sexes (r2 = 0.91), all indicating negative allometric growth. The reproductive period extended from April to August, as confirmed by gonadosomatic index (GSI) values and histological section taken together with ovarian development supports this condition. Fecundity ranged from 46 to 205 eggs per female, with an average of102.5 +/- 1.8. Seasonal and spatial analyses revealed significantly higher abundances in the & Ccedil;ayeli station, particularly at depths greater than 20 m during autumn. Catch per unit effort (CPUE) varied significantly across depth, season, and station groups (P < 0.05). These findings contribute valuable information for future conservation efforts targeting H. guttulatus populations in the region.