Effect of temperature on growth and survival of Crassostrea corteziensis spat during late-nursery culturing at the hatchery

Nine temperatures (16, 18, 20, 22, 24, 26, 28, 30, and 32 degrees C) within the natural range of distribution of the Cortez oyster Crassostrea corteziensis were tested in a first experiment to determine the optimal temperature for growth and survival. Based on these results, a second study assessed two temperatures above this range (34 and 36 degrees C) to determine upper median lethal temperature for the species. The species was thermo-tolerant between 16-32 degrees C, grew faster and larger at 24 to 30 degrees C, and had optimal growth at 28-30 degrees C. The lower tolerance of the species appears far from the lowest value tested (16 degrees C). In contrast, the upper tolerance temperature was near 32 degrees C, since 100% spat mortality occurred within 96 h at 34 and 36 degrees C. These results are being used to develop a protocol for large-scale hatchery culture of the species in Mexico. (D 2007 Published by Elsevier B.V.