The fish assemblage on the coastal shallow waters of the Gulf of Odessa and its diel changes

Abstract

The species composition and number of fishes were studied in the northern the part of the Gulf of Odessa an hour before the dawn, during the dawn, and two hour after dawn. Among 47 fish species recorded in the Gulf of Odessa [3], we have recorded 28 species during 2011–2014, which makes 60 % of its recent fish fauna. The maximal species number observed in 2014 (25 species), and the minimal one was in 2012 (9 species). Two fish species, the Prussian carp (Carassius gibelio) and the redlip mullet (Liza haematoheilus), are the non-indigenous species. The Gobiidae family is richest presented; 10 fish species have been recorded. The data on the fish fauna diel changes are new for the Black Sea and presented for the first time. Among the dominant fish species, which showed the diel changes in its number, we found the big-scale sand smelt (Atherina boyeri) and the golden gray mullet (Liza aurata). The tendency to reduce the number of fishes after sunrise has been recorded. The Gulf of Odessa is significantly diffe­rent from the data presented in other European coastal water by the composition of fish taxa, which demonstrates the diel changes. Because of the general poorness of the Black Sea fauna in comparison with the other European seas, the numerous species, the big-scale sand smelt, occupy the niche which is occupied by the other Mediterranean and Atlantic species.

Keywords

• Gulf of Odessa
• Black Sea
• changes
• ichthyofauna