Abstract
Why is the fish catch per unit area so high in the Seto Inland Sea, Japan, compared to other semi-enclosed seas, such as Chesapeake Bay, USA, and the Baltic Sea? To answer this question, it is necessary to understand the production process in the lower trophic levels of the food chain on which fish production depends. A cooperative research was conducted once per season in 1993 and 1994 to investigate the biological production in the lower trophic levels in the Seto Inland Sea, and revealed that the sea is characterized by high production rates of phyto- and zooplankton and high efficiency of energy transfer between trophic levels of the food chain. It is our responsibility to preserve the health of this productive and efficient ecosystem in order to sustain fishery production in the future.
