Ecological variability of allometry parameters of the Black Sea mussels shells in the north-western part of the sea

Abstract

The ecological variability of allometric parameters of the mussel Mytilus galloprovincialis Lamarck, 1819 from different regions of the northwestern Black Sea, significantly differing in hydrological and hydrochemical conditions, the nature of the bottom, depth, distance from the coast, the degree of influence of large rivers flow was shown. As the main integral ecological indicator in the analysis of this variability, we used the mussel habitat depth, which largely determines the level of illumination, temperature regime, as well as the nature of the food supply of mollusks. With an increase in depth from 7 to 30 m, the degree coefficient in the allometric equation for the connection between shell mass and total mollusk mass increases from 0.85 to 1.04. Using correlation and regression analysis, a directly proportional dependence of this coefficient (r = 0.8094) on the depth of the animals habitats was demonstrated. Mussels from shallow coastal areas, as well as under the influence of the Danube waters, showed negative allometry of the studied parameters. The percentage of shell mass in the total wet mass of these mussels ranged from 34.9 to 53.7 %. Mollusks from relatively deep-water areas, the most distant from the mouths of the rivers in the studied ratio showed positive allometry. The percentage of shell mass in the total wet mass of mussels from these areas was 46.9–69 %.