Adult threadfin shad, Dorosoma petenense (Gunther), were stocked alone in ponds at rates from 100 to 1,600 per acre to determine the most efficient rate of stocking for maximum production. Total production varied from 84.5 to 290.0 pounds per acre while net production ranged from 36.4 to 169.0 pounds per acre. The number of young per surviving parent varied from 1,392 at a stocking rate of 100 adults per acre to 82 young at a stocking rate of 1,600 adults per acre. Threadfin shad stocked in April spawned from May (76°F) through August. The net production of threadfin and gizzard shad, Dorosoma cepedianum (LeSueur) stocked at 200 per acre was 70.0 and 85.5 pounds per acre, respectively. Gizzard shad spawned 2 months before the threadfin and both species grew at the same rate. Threadfin shad stocked together with other species gave varying results. Young-of-the-year shad were completely eliminated in one pond containing largemouth bass, Micropterus sulmoides (Lacepede), and bluegill, Lepomis macrochirus Rafinesque.