Cumulative stress-induced mortality of gizzard shad in a southeastern U.S. reservoir

Starvation was apparently responsible for a large die-off of gizzard shad, Dorosoma cepedianum , in several east Tennessee reservoirs during the spring of 1983. Condition indices, calorific equivalents, lipids, and blood parameters of electrofished (control) shad from Watts Bar Reservoir were significantly higher than these parameters for recently dead shad and for stressed shad, indicating that the stressed and dead fish were at similar levels of physiological condition. The authors hypothesize that mortality due to starvation resulted from a year-long series of unusual environmental conditions beginning with an abnormally warm spring in 1982 which delayed spawning for some shad, a mild winter in 1982-1983 which increased metabolic demands, and an unusually cool spring in 1983 which delayed food availability.