Lowered temperature and reduced salinity retarded development of early life history stages of Acropora valida from the marginal environment

Abstract To better understand the possible consequences of the co-occurrence of salinity and temperature stresses on reef building corals in subtropical marginal environment, laboratory based experiments were conducted on early embryonic developmental success of the newly fertilized eggs of Acropora valida from Hong Kong under different interactive temperature [24, 27 (ambient), 30 °C] and salinity [33 psu (ambient), 30, 28, 26 psu] treatments. Our results showed the effect of temperature to be comparatively stronger than that of salinity in affecting rate of embryonic development. There was a 4 h delay in embryonic development at lowered (24 °C) and slightly accelerated development at elevated (30 °C) temperatures. In addition, the interaction of temperature and salinity significantly affected the proportion of abnormal embryos. At 27 °C and 30 °C, the percentage of developmental abnormalities was generally low (