Some population parameters of Ruditapes philippinarum (Bivalvia, Veneridae) on the southern coast of the Marmara Sea, Turkey

摘要

Ruditapes philippinarum, a venerid clam, is a dominant species in the sandy and muddy areas in the coastal waters of the Marmara Sea. Intensive commercial harvesting of this species is conducted in these regions. We studied the population dynamics of R. philippinarum on the southern coast of the Marmara Sea (Bandirma). Samples were collected on a monthly basis between September 2012 and August 2013. Seasonal von Bertalanffy growth parameters using the length-frequency distribution of R. philippinarum were estimated at L_∞ = 67.50 mm and K = 0.33 year~(-1), and the seasonal oscillation in growth rate was 0.53. The slowest growth period was in January. The growth performance index and potential lifespan were 3.182 and 8.06 years, respectively. The growth relationship was confirmed to have a positive allometric pattern. The average total mortality rate was estimated to be 0.777 year~(-1), whereas the natural and fishing mortality rates were 0.539 and 0.238 year~(-1), respectively. The current exploitation rate of R. philippinarum was 0.306. The recruitment pattern peaked during June-August, and spawning occurred between May and August. The results of this study provide valuable information on the status of R. philippinarum stocks.