On the population dynamics of young of the year striped seabream, Lithognathus mormyrus (Linnaeus, 1758), in Dardanelles (Çanakkale)

The main purpose of this study was to determine the population parameters such as abundance, spatial and temporal distribution, daily age, daily growth rate, mortality and hatch date distributions and also examine feeding habits and the effects of seasonal changes on food preferences of young of the year (YOY) striped seabream, Lithognathus mormyrus (Linnaeus, 1758), in Canakkale shallow waters. Samplings were conducted with a beach seine in 39 different stations between 2006 September to 2007 December. A total of 938 YOY striped seabream, with total lengths ranging between 20 and 139 mm TL were captured. The youngest daily age reading was 30 day whereas the oldest age was 307 days. Individual daily growth rates were estimated between 0.325 and 0.762, with mean of 0.526 ± 0.002 mm day-1. Significant differences were found between seasons in which striped seabream hatched (ANOVA: P < 0.001, F = 191.1). The relationship between age and otolith length and otolith width was linear. Growth rates decreased as age increased. Significant difference were found for the linear regression of age, otolith length (?2 = 1.44, P < 0.0001) and otolith width (?2 = 2.34, P < 0.0001). Hatch date distributions extended from April to January with relatively higher frequencies between June and September. Mortality rates were estimated as 0.0224 and instantaneous daily mortality rates were estimated as 2.21%.Based on stomach content analysis, among the main prey categories, crustacea (%N = 92.56) was the most preferred food group, followed by foraminifera (%N = %5.18). Present results indicate that young of the year striped seabream populations inhabiting the Canakkale shallow waters were carnivorous fish and the main food source were copepod species. Significant differences were not found among seasonal diet composition (ANOSIM: R = 0.24, P > 0.05).Keywords: Canakkale, Striped Seabream, Daily Age, Daily Growth, Mortality, Feeding Habits