D.H. Hurley, R.L.Walker-1997
J. World Aq. Soc., 28(4): 407-411
Abstract:
Parameters associated with optimum larval-rearing conditions are important in developing the culturing protocol of potential aquacultural species, and have yet to be addressed in terms of water temperature and salinity for Spisula solidissima similis, the southern Atlantic surfclam. Hatchery spawned S. s. similis larvae were seared to late pediveliger stage in five simultaneously conducted water temperature and salinity treatments. This larval growth and survival experimentation consisted of three salinity treatments (15, 25 and 30 ppt) in conjunction with a water temperature of 20 C, and two water temperature treatments (15 and 25 C) in conjunction with a salinity of 25 ppt. In the 20 C temperature treatment, significantly higher larval survival and greater growth occurred (both, P < 0.0001) as compared to the 15 C and 25 C treatments by day 22. Complete larval mortality occurred in the 20 C, 15 ppt salinity treatment by day 4. No significant differences in larval survival occurred between the 25 ppt, 20 C and 30 ppt, 20 C treatments by day 22 (P = 0.714). However, significantly greater larval growth occurred in the 25 ppt, 20 C compared to the 30 ppt, 20 C treatment (P = 0.009). The optimum rearing temperature and salinity for hatchery spawned S. s. similis larvae to late pediveliger stage are 20 C and 25 ppt, respectively, within the temperature and salinities tested.
(Shellfish Aquaculture Laboratory, University of Georgia, Marine Extension Service, 20 Ocean Science Circle, Savannah, Georgia 31411-1011 USA)