Morphometric aspects and growth modeling of exotic bivalve blood cockle Scapharca inaequivalvis from the Black Sea, Turkey

Abstract

This study was planned to determine biometric features and relationships between them in blood cockle, Scapharca inaequivalvis, a benthic exotic bivalve species of the Black Sea, Turkey during a period of 12 months. Over the study, 4,543 samples were collected and their shell length (SL), width (SWi), thickness (ST) and weight (SWe), as well as total (TW) and meat weights (MW) were measured. SL changed between 0.45 and 7.18 cm with an average value of 3.77 +/- 0.02 cm. Average TW of the samples was 22.37 +/- 0.26 g. Average MW of S. inaequivalvis was calculated as 10.66 +/- 0.32 g with a rate of 26.85% of TW. The findings obtained showed that monthly measurements of SWe and MW had a small variation. On the other hand, monthly ST varied greatly. SL and SWe increment (%) models were also generated according to SL classes using regression analysis. Correlation and cluster analysis showed that MW had a weak association with other variables. The strongest correlation was between ST and SWe in October (R-2 = 1.0). The results present valuable information for this exotic species but more studies are required to better understand its biological characteristics and long term effects on the ecosystem.