Year-round production is a top priority of hybrid striped bass producers. Most Morone culturists produce sunshine bass (white bass Cf X striped bass d') that have very tiny fry and require rotifers as their first food. Almost 100 percent of the fingerlings are produced in ponds where high survival rates depend on fry being stocked at the right time -before rotifer concentrations peak and before copepods appear. Pond culture drawbacks include the inability to monitor growth and survival and seasonal limitations due to weather. Tank culture overcomes these problems and is necessary for year-round production. Little tank fingerling production has occurred because costs are higher than for pond culture. Supplying live food is a major expense. Sunshine bass larvae are stocked at 4 to 5 days post hatch (dph) and are fed enriched cultured rotifers. The rotifers require microalgae. Within a few days the fry are weaned to cultured Artemia nauplii. The culture of the larger palmetto bass and striped bass starts with feeding Artemia nauplii. By about 15 dph, weaning to an artificial diet begins and is completed by 26 dph. Grading at that time reduces cannibalism. Live food culture is risky, and requires time, space, costs, and expertise. Recent innovations may alleviate some of these problems. High-density (up to 16,000/mL) rotifer production methods are being developed. These systems require constant feeding, oxygen, pH and ammonia control, suspended particle removal, and proper harvesting. Fatty-acid enriched algae pastes can replace cultured algae. Ammonia and pH problems can be controlled with products like Chloram-X® and auto-sensing pH controllers. Water is conserved by utilizing recirculation systems for rotifer and fingerling production. Use of commercially available decapsulated brine shrimp eggs further reduces time and physical risk. Increased demand for fingerlings during the winter and reduced culture costs will increase tank fingerling production.
INTRODUCTIONYear-round production of sunshine bass is a top priority of hybrid striped bass producers (Anonymous 1998). Currently, fry and fingerling production is confined to March through June, the normal spawning periods of the parental stocks (Mike Freeze, Keo Fish Farm, personal communication; Becker 1983). Fish reach market-size in 10 to 20 months after hatching, depending on stocking rates, culture conditions, and diet (Carlberg et al. 1989). As a result, it is difficult for fish farmers to provide hybrid striped bass of uniform size and quality to markets yearround. Consequently, prices also vary considerably during the year. It is important to develop culture techniques that will provide for year-round availability of sunshine bass fingerlings.The culture of striped bass (Marone saxatilis) and its hybrids with white bass (M. chrysops) for the food-fish market is a recent endeavor. The initial incentive for Marone culture was to replenish wild populations of striped bass whose stocks had been depleted by over-fishing and habitat degradation. However, hybrid...