THE INFLUENCE OF TURBIDITY ON LARVAL WALLEYE, STIZOSTEDION-VITREUM, BEHAVIOR AND DEVELOPMENT IN TANK CULTURE

The behavior and development of larval walleye, Stizostedion vitreum, cultured in clear and turbid water in laboratory aquaria are compared from hatch to 17 days post-hatch. Significant differences (P less than or equal to 0.05) in larval distribution and swimming speed were obse rved. In clear water, larvae showed a strong association with the side s of the aquaria, but in tanks with turbid water, larvae avoided the s ides of the aquaria. Larvae in turbid water had greater average swimmi ng speeds, faster growth rates, and improved gas bladder inflation (GB I) than larvae cultured in tanks with clear water. There were no signi ficant differences between the two treatments in larval survival or ca nnibalism. Larval viability (survival X GBI) was three times greater i n turbid water (19.0%) than in clear water (5.7%). The improved perfor mance and viability in turbid water are attributed to the changes in l arval distribution as a consequence of larval reaction to diffused lig ht in turbid water. (C) 1997 Elsevier Science B.V.