Spatio – temporal variability in composition of inshore juvenile fish populations along the west coast of Istra, northern Adriatic

Abstract

      A total of 5601 fishes belonging to 13 families and 38 species were caught in May (1361), July (3192), September (574) and November (474), 2000; on 3 locations (Tar Cove, Mirna Estuary and Marić Cove) along the west coast of Istra, Croatia; using a 50 m long beach seine. Five species, Atherina hepsetus (47.47%), Atherina boyeri (27.73%), Diplodus annularis (9.96%), Pomatoschistus marmoratus (1.62%) and Liza aurata (1.54%) comprised 88.32% of the total catch. The community structure was specified by species richness (D), diversity (H), evenness (J), and JACCARD similarity coefficient (K). The annual value of D was 4.29, ranging from 0.84 (Mirna Estuary in May) to 3.19 (Tar Cove in September). H values ranged from 0.17 (Tar Cove in May) to 2.45 (Marić Cove in May), with annual value of 1.66. The overall value of J was 0.46, ranging from 0.01 (Tar Cove in May) to 0.25 (Marić Cove in November). The coefficient K was highest between Tar and Marić Coves in May (0.68) and had a lowest value between Mirna Estuary and Marić Cove in September and November, and also between Tar Cove and Mirna Estuary in May (0.52). Preliminary results of the present study provide a basis for future studies of aspects that may influence the distribution and abundance of juvenile fishes during different seasons along the west coast of Istra.