FILTRATION ABILITY OF MUSSELS OF DIFFERENT PHENOTYPES OF ODESA DISTRICT OF THE BLACK SEA

Abstract

Introduction. Мussel Mytilus galloprovincialis (Lamarсk, 1819) is an active filter feeder of seawater, it has an important role in the processes of biological self-purification of seawater. By the nature of distribution of the purple pigmentation in the outer prismatic layer of the mussel shell 3 phenotypic groups are distinguished: Fа – the pigment is absent, Fb – the pigment colours the whole shell, Fc – the pigment is located in form of radial strips alternating with non-pigmented zones.The purpose of the work is to study the filtration ability of various mussel phenotypes.Method. The mussels collected in April 2014 at the water temperature of 12°C served as the material. The research includes a two-week acclimation of the mussels in the natural sea water with an initial salinity. The experiments were carried out in the temperature range from 10°C to 30°C, with the temperature step being 2°C. In total 660 specimens of the mussels were processed and analysed.Results and conclusions. It was found that in the entire investigated temperature range of water part of filter feeder young mussels for all phenotypes of constituted: at 10°C –16-18 %; at 12°C – 48 %; at 18°C – 88 %, (reaching the optimum); at 20°C – 70-73 %, and at 24°C – 36-38 %. It was determined that at 10, 20 and 24°C, the proportion of adult filter feeder mussels decreased from phenotype Fа to Fb and Fc. At 16°C the filtration activity was characteristic of mussels of all phenotypes. At 18°C the maximum of filter feeder mussels was observed in phenotype Fа (98 %); and in each of phenotypes Fb and Fc – 91 %. It was found that at the maximum temperature of the water 30°C in young mollusks and adult mussels of all three phenotypes part of filter feeder individuals is nearly constant – from 3 to 5 %.