Eleven rotenone studies were evaluated with SCUBA gear between 1961-1964 to determine the numbers and weights of fish that do not float to the surface and are not recovered. It was determined that 74% of the number and 95% of the weight of all fishes present in the sample area were recovered on the surface within a 52-hour period. Fingerling fishes represented 91% of the unrecovered population by numbers; intermediates, 6%; and harvestable-size fish, 3%. The species of fish which were lost in the greatest numbers were threadfin shad, brook silverside, gizzard shad, black bass and white crappie, respectively. The highest percentage of recovery occurred during the month of September with the low recorded in August. Species composition and size distribution affected the recovery of fish more than other factors.