Long-term fluctuations in the catch data of konoshiro gizzard shad, Konosirus punctatus, around Japan

摘要

A konoshiro gizzard shad. Konosirus puncratus (TEMMINCK et SCHLEGEL) distributed in the estuaries and coastal waters around Japan is a traditional eatable fish in Japan. In this paper, we describe the long-term fluctuations of the species around Japan based on the national and prefcctural catch data from 1894 to 1999. The results were obtained as follows : 1) long-term fluctuations of K. punctatus with two high-level catch periods during 1930s and 1980s were similar to those of the Japanese sardine.Sardinopa melanostictus (SCHLEGEL); 2) in 1990s the Japanese sardine catch reduced abruptly, the species was maintaining the high-level catch following the peak period in 1980s because of catching by the purse seines as a primary forage for fish cultureinstead of the Japanese sardine in Tokyo Bay. Ise Bay. Osaka Bay and so on; 3) some temporary rises in catch at intervals shorter than 10 years were frequently observed in the main fishing grounds of the species.