Freshwater Drum Spawning and Fecundity in the Upper Mississippi River

One hundred freshwater drum ovaries from 1981 collections were examined to provide spawning and fecundity information for the long-term fisheries monitoring program at the Quad Cities Nuclear Power Station. Objectives were to estimate freshwater drum fecundity in the Upper Mississippi River and relate sexual maturity to size or age. The mean fecundity estimate for ripe fish was 85,800 ova per female. Total estimated number of ova showed no relationship with length or weight, but there was a relationship with age. Mean number of ova for a given age group increased with age. Female freshwater drum in Pool 14 may become sexually mature at age 4, but females age 5 and older comprised over 95% of the 100 females representing the spawning population