Shell growth and reproductive cycle of the Mediterranean mussel Mytilus galloprovincialis in Tokyo Bay, Japan: relationship with environmental conditions

Abstract

This study investigates shell growth patterns and the reproductive cycle of the Mediterranean mussel Mytilus galloprovincialis in Tokyo Bay, central Japan. A follow-up study of marked mussels within the intertidal zone from July 2007 to September 2008 indicates a remarkably fast annual shell-growth rate and a short life span, reaching the maximum shell length (ca. 70 mm) at age 3 or 4 years. Histological examinations of mussel gonads collected fortnightly revealed that the Tokyo Bay population has a spawning season between late autumn and spring, and attains sexual maturation several months after recruitment. Shell growth patterns for individual mussels show seasonal variations, with high shell-growth rates during spring and summer, and minimal growth from late autumn to early spring. Slow shell growth during winter is possibly controlled by combined environmental (lower air and seawater temperatures, and scarce phytoplankton) and physiological (the reproductive effort expended in gametogenesis and spawning) factors.

Enhanced Growth Rates of the Mediterranean Mussel in a Coastal Lagoon Driven by Groundwater Inflow

“…They observed that the number of growth increment formed during a limited interval of time is (sometimes significantly) lower than the number of days (or tides) at the study sites. Winter growth cessation is indeed common in bivalves (Jones and Quitmyer, 1996;Tanabe, 2007;Okaniwa et al, 2010), because the production of shell carbonate ceases below species-specific growth temperature thresholds. For instance, Margaritifera margaritifera in northern Sweden stops producing shell carbonate below 5 • C (Schöne, 2008) while M. galloprovincialis from Tokyo Bay, Japan, stops growing or barely grows for water temperature between 8 and 14 • C (Okaniwa et al, 2010).…”

“…Winter growth cessation is indeed common in bivalves (Jones and Quitmyer, 1996;Tanabe, 2007;Okaniwa et al, 2010), because the production of shell carbonate ceases below species-specific growth temperature thresholds. For instance, Margaritifera margaritifera in northern Sweden stops producing shell carbonate below 5 • C (Schöne, 2008) while M. galloprovincialis from Tokyo Bay, Japan, stops growing or barely grows for water temperature between 8 and 14 • C (Okaniwa et al, 2010). Growth cessation may also occur all year round as a result of an abrupt change in the environmental conditions due to strong wind events, drop in salinity and/or phytoplankton bloom (due to toxicity or clogging of the gill system) (Page and Hubbard, 1987;Chauvaud et al, 1998;Schöne, 2008;Okaniwa et al, 2010).…”

“…For instance, Margaritifera margaritifera in northern Sweden stops producing shell carbonate below 5 • C (Schöne, 2008) while M. galloprovincialis from Tokyo Bay, Japan, stops growing or barely grows for water temperature between 8 and 14 • C (Okaniwa et al, 2010). Growth cessation may also occur all year round as a result of an abrupt change in the environmental conditions due to strong wind events, drop in salinity and/or phytoplankton bloom (due to toxicity or clogging of the gill system) (Page and Hubbard, 1987;Chauvaud et al, 1998;Schöne, 2008;Okaniwa et al, 2010). The observed discrepancy in days and growth increments in this study is small in comparison to those observed at many other sites, likely due to the comparatively stable environmental conditions in the lagoon, but nevertheless suggests that the conditions temporarily cause either a complete cessation of growth during specific days or a desynchronization in the circadian rhythm of growth increment deposition (Chauvaud et al, 2005).…”

Effects of temperature change on mussel,Mytilus

“…The timing and success of reproduction is heavily weighed upon temperature and food availability (Sastry 1966;Suarez et al 2005;Lemaire et al 2006;Okaniwa et al 2010). For example, mussels (M. californianus) near the high edge of the mussel bed invested less energy into reproduction and spawned early in the summer compared to those in the lower edge, where food availability was high and reproduction occurred throughout the year (Petes et al 2008).…”

Environmental influence on calcification of the bivalve Chamelea gallina along a latitudinal gradient in the Adriatic Sea

“…Previous studies identified several drivers that influence the shell growth rate of bivalves including temperature 5,6 , food supply and quality 7,8 , salinity 9 , latitude 1 and also reproduction 10 . Evidence for modification in growth in marine molluscs with the environment comes for example from the great scallop Pecten maximus along the Northeast Atlantic coast 1 and from the Mytilus edulis along the British coast in the Irish Sea 11 , showing a decrease in shell growth with higher temperatures.…”