Growth of the Manila clam Ruditapes philippinarum in Sanbanse, the shallow coastal area in Tokyo Bay

Abstract

: A new cohort of the Manila clam Ruditapes philippinarum was established in Sanbanse (the shallow coastal area of Tokyo Bay) during October–November 1998. Growth of clams within this cohort was monitored monthly or bimonthly at five stations along an inshore-offshore transect in Sanbanse through November 1999. Mean shell length was about 0.4 mm in November 1998 and increased gradually to about 1 mm in March 1999. The clams then grew rapidly during the warm season and mean shell length reached 25–29 mm in November 1999 at each station. Comparisons of growth among stations in terms of shell length and soft-body dry weight suggest that the growth of R. philippinarum was faster at offshore than inshore stations during warm periods.