Mike Van Den Avyle, Cooperative Research Units Program, 1875 Century Blvd., Suite 200, Atlanta, GA 30602

Abstract. Hatchery production objectives have often been viewed as constraints rather than components of fishery management efforts. In many cases, the lack of knowledge of fish performance in receiving waters has impaired the development of clear objectives for hatchery production, essentially decoupling management into separate "hatchery" and "post-stocking" phases. This separation often prevents optimization of the overall management effort. In a study of post-stocking survival of striped bass Morone saxatilis in the Savannah River, GA-SC, the relative cost and survival of three size classes of hatchery-reared fish were evaluated during 1990-1996. Based on per-fish production cost, stocking of the smallest size class (phase I, 20-35 mm TL) would have been recommended. However, by adding information obtained for estimated survival of fish at 48-h post-stocking, it was concluded that the intermediate size class (advanced phase I, 60-80 mm) was superior. However (again), by adding information about survival of stocked fish to age 2, the largest size class (phase II, 175-250 mm) was considered optimal for future stocking efforts. Differences between conclusions reached at various points in the rearing-stocking chronology indicate the sensitivity of management decisions to the type of information available and the need for comprehensive information to allow a (seemingly) correct decision. In this case, recruitment to the adult stock was optimized by stocking fewer, larger, more costly fish, and the findings were incorporated into hatchery production objectives.