Influences of temperature on development and survival, reproduction and growth of a calanoid copepod (Pseudodiaptomus dubia).

ABSTRACT

Pseudodiaptomus dubia is a calanoid copepod that is distributed widely in the estuarine-coastal waters of Asia and is a dominant copepod in the shrimp grow-out ponds in southern China. A laboratory culture experiment was conducted to evaluate the influences of water temperature on larval development, survival, and reproduction. Results indicate that within a temperature range from 15 to 35 C degrees, larval development increases as the temperature increases. The water temperature for optimal larval survival rate ranges from 20 to 35 C degrees. Longevity and egg hatching time decrease as the temperature increases from 20 to 35 C degrees. Total fecundity and reproduction frequency increase as the water temperature increases, with the maximum at 30 C degrees. Fecundity and reproduction frequency decrease when the temperature exceeds 30 C degrees. Intrinsic growth rate [r(m)] ranges from 0.168 to 0.195 at 25 to 30 C degrees; net reproduction rate [R(0)] and finite growth rate (lambda) are 163 to 264 and 1.183 to 1.215, respectively, when the temperature is greater than 20 and 35 C degrees; population doubling time (t) varies from 3.556 to 4.128 days at temperatures less than 20 and 35 C degrees. Population generation time (T) is negatively correlated with temperature, with the optimal population growth rate at 25 to 30 C degrees.