Abstract

Samples of Corbicula japonica in the Seomjin River were collected from March 2016 to November 2016. Age of C. japonica was determined from the rings on the shell. The relationship between shell length (SL; mm) and shell height (SH; mm) was expressed by the following equation : SH = 0.8981SL - 0.4166 (R2 = 0.97), and between shell length (SL) and shell width (SW; mm) by the equation SW = 0.5715SL + 0.1583 (R2 = 0.95). Shell length (SL; mm) and total weight (TW; g) relation was also expressed by the following equation : TW = 0.0003SL3.0078 (R2 = 0.97). Based on the monthly variations in the marginal index (MI) of the shell, it is assumed that the ring of this species was formed once a year during the period of March. The time it takes to form the ring is estimated to be about 7 months (0.58 years). von Bertalanffy's growth parameters were estimated using the regression wizard of Sigmaplot (Systat Software, Inc., v. 10.0), a computer program. Maximum shell length (SL∞) was 40.1455 mm, growth rate  was 0.3564/year, theoretical age at 0 shell length (t0) was 0.0644 year, and asymptotic total weight (TW∞) was 19.98 g. Growth curves for shell height (SH) and total weight (TW) fitted to the von Bertalanffy's equation were expressed as follows : SLt = 40.1455(1―e―0.3564(t―0.0644)) TWt = 19.98(1―e―0.3564(t―0.0644))3.0078