Survival and Growth of Red Drum Sciaenops ocellatus in Saline Groundwaters of West Texas, USA

Abstract

Abstract.— West Texas saline groundwaters were assessed as potential media for culturing red drum, Sciaenops ocellatus. In 30‐d bioassays with juvenile red drum (0.4–3.0 g), highest survival was 85% in a 5‐ppt (parts per thousand = g/L) salinity, high‐sulfate (1,723 mg/L SO4‐2), high‐calcium (427 mg/L Ca±2) groundwater from a windmill catchment pond in Pecos County. The lowest survival was 0% in a 35‐ppt saline groundwater from a gravel pit, also in Pecos County. In complementary bioassays of low‐salinity (<5 ppt) groundwaters from the same region, calcium chloride (CaCl2) addition to a 3‐ppt. Reeves County ground‐water low in Ca±2 resulted in the greatest increase in survival (0–93). It was unclear whether the beneficial effect of CaCl2 was a result of increasing Ca±2 concentration (36–336 mg/L), increasing Cl‐ concentration (639–1,296 mg/L). or both. The concentration of total dissolved solids (“salinity”) appears to be the single most important consideration in estimating the red drum aquaculture potential of a groundwater, with the optimum salinity being 5–15 ppt. Concentrations of arsenic (As), cadmium (Cd), chromium (Cr), mercury (Hg), lead (Pb), and selenium (Se) tended to be higher in west Texas groundwaters than in typical U. S. surface waters. However, based on current maximum tolerable daily intake recommendations, red drum cultured for 30 d in west Texas groundwaters contained whole‐body As, Cd, Cr, Hg, Pb, and Se concentrations that would not pose a substantial health risk to adult human consumers.