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Zimpfer, S. P., C. F. Bryan and C. H. Pennington (1987). Factors associated with the dynamics of grass carp larvae in the Lower Mississippi River Valley. Pages 102-108 in R. D. Hoyt, ed. Proceedings of the 10th Annual Larval Fish Conference, American Fisheries Society Symposium Serial, Miami, Florida (USA).

Larvae of grass carp Ctenopharyngodon idella were captured in 4 major rivers of the lower Mississippi River valley. Catches were greatest in the lower Red River; peaks were associated with increasing river stage, current speeds of 1.2- 2.2 m/s, water temperatures of 23.5-28.2 °C, pH values of 7.2-7.7, dissolved oxygen concentrations of 4.0-7.6 mg/L, and secci disc readings of 1-9 cm. Catches were least near navigation locks and dams on the Ouachita River, where flows were 0.6 cm/s or less when water temperatures were optimum. Intermediate catches of larvae were taken from the Atchafalaya River and the Mississippi River Diversion Channel. Major spawning areas in the Mississippi and Red rivers were located in or near Arkansas, where grass carp were first released. The occurrences of juveniles and adults in commercial catches from the Black, Mississippi, and Red rivers, and of newly hatched larvae in the backwaters of the Atchafalaya River basin, suggest that grass carp are successfully recruited to fish stocks of the lower Mississippi Valley.