原著論文
東京湾産シャコの浮遊期幼生における塩分耐性
2003 年 67 巻 3 号 p. 141-147
詳細
2003 年 67 巻 3 号 p. 141-147
Our previous study suggested that the increase in river runoff that can cause a decline in surface salinity, could affect decreases in recruitment of the Japanese mantis shrimp Oratosquilla oratoria in Tokyo Bay. In the present study, salinity tolerance of the pelagic larvae of O. oratoria was tested under rearing conditions. A survival test for 72 hours on the third stage larvae was conducted under 15 combinations of different temperatures (20, 25 and 30°C) and salinities (10, 15, 20, 25 and 31 psu) with two desalination methods (rapid and gradual). The survival rate of the third stage larvae declined greatly at 10 and under 15 psu with gradual and rapid desalination, respectively. A survival test was also conducted on the fifth stage larvae under five-salinities level at 25°C with gradual desalination, and showed that a high survival rate was sustained after 72 hours even in 10 psu salinity. Effects of low salinity on the survival of the pelagic larvae under natural conditions in Tokyo Bay are discussed on the basis of the results of the survival tests under rearing conditions.
