Spatial and temporal variations in the species composition and abundance of benthic macroinvertebrates along the coast of the Eastern Black Sea

Abstract

ABSTRACT The species composition and abundance of benthic macroinvertebrates in the Eastern Black Sea were determined seasonally, between May 2013 and February 2014. Sediment was collected using a Van Veen grab, at different depths: 5–15 m, 15–25 m, 25–35 m and >35 m. A total of 320 hauls were undertaken at 80 stations, and 90 species were identified, from seven phyla and 47 families. Overall, Mollusca was the most diverse phylum, with 32 species, followed by Annelida (32) and Arthropoda (13). The most abundant species was Chamelea gallina, which accounted for 37% of the total number of individuals, followed by Gouldia minima (25%) and Pitar rudis (10%). Based on seasonal variations, 62 species were identified in winter, 59 in summer, 54 in spring and 46 in autumn. The highest abundance was recorded in summer, representing 37.8% of the total abundance, followed by spring (25.2%). The species with the highest abundance in all four seasons was C. gallina followed by G. minima. Also, C. gallina followed by G. minima was the most abundant species in Samsun, Ordu, Giresun and Trabzon, whereas in Rize and Artvin, the most abundant species was G. minima followed by C. gallina. The results of this study should provide baseline data for future monitoring, to understand the consequences of natural or anthropogenic disturbance on the species composition and abundance pattern of the benthic macroinvertebrate community along the coast of the Eastern Black Sea.