Assessment of Floating Vertical Raceways for the Culture of Phase‐II Hybrid Striped Bass

Abstract

A floating vertical raceway is a system designed to provide a constant, unidirectional flow of water to fish confined in a flexible raceway that is suspended vertically in the water column. This study evaluated the potential of floating vertical raceways for the culture of phase‐II sunshine bass (female white bass Morone chrysops × male striped bass M. saxatilis) reared at two densities (125 and 188 fish/m3). Fish with a mean starting weight of 0.7 g were fed a diet containing 40% crude protein to satiation for 121 d. Fish in the low‐density treatment reached a significantly higher final mean weight (160.0 g) than those in the high‐density treatment (136.9 g). Survival was also significantly higher in the low‐density treatment (81.1%) than in the high‐density treatment (73.8%). No significant differences in water quality were detected for dissolved oxygen, total ammonia, un‐ionized ammonia, or temperature between high‐density and low‐density treatments. Unlike the surrounding reservoir, water temperature inside the raceways remained destratified throughout the growing period. Based on the performance of fish, the high water quality maintained inside the enclosures, and ease of use, the floating vertical raceway system offers considerable promise as an alternative rearing system for deepwater impoundments.

Effect of Stocking Rate on Growing Juvenile Sunshine Bass, Morone chrysops × M. saxatilis, in an Outdoor Biofloc Production System

“…Although overall fish survival was acceptable and within limits reported for growing sunshine bass fingerlings in ponds (D'Abramo et al ; Turano et al ) or in a prototype floating vertical raceway (Volkman et al ), the mechanism by which TSS concentration appeared to affect sunshine bass survival negatively is not known. In larval sunshine bass production in tanks, increasing survival was associated with elevated turbidity levels and was attributed to a decrease in cannibalistic interactions between the fish (McEntire et al ).…”

“…Sunshine bass have been grown successfully at high stocking and feeding rates in vertical raceways (Volkman et al ) and recirculating aquaculture systems (RAS; Kemeh and Brown ; Rawles et al ), but this is the first report of growing sunshine bass in a near‐zero‐water‐exchange BFT production system. Phytoplankton uptake and nitrification in the outdoor BFT system function to maintain good water quality, mainly low NH 4 ‐N and NO 2 ‐N concentrations, in response to high feeding rates, which combined with high stocking and aeration rates, increase fish yields.…”

“…REs, however, were poor because of the poor feed efficiencies that resulted from overfeeding the fish. Feed efficiency reported for sunshine bass ranges from 0.37 to 0.94 (Kelly and Kohler ; D'Abramo et al ; Volkman et al ; Rawles et al ). Although fish were fed daily to apparent satiation, several factors likely contributed to the overfeeding.…”

Comparison of Pond Production of Phase‐III Sunshine Bass Fed 32‐, 36‐, and 40%‐Crude‐Protein Diets with Fixed Energy: Protein Ratios

“…Utilization of diets wherein similar amino acid profiles are maintained will probably provide for greater control than the use of diets with highly variable amino acid profiles, as is often the case in studies where the reduction of protein and/or energy is considered exclusively. Application of this formulation strategy may permit reductions in dietary protein while still maintaining optimal growth Methods Fish husbandry.-Sunshine bass reared in vertical raceways at the Southern Illinois University-Carbondale pond complex until the onset of phase III (see Volkman et al 2004) were stocked on 8 March 2002 into 0.04-ha ponds (n ¼ 12) at a density of 6,188 fish/ ha. Ponds were aerated continuously by use of 1-hp paddle-wheel aerators.…”