Comparing and Connecting Growth, Surface Feeding, and Catchability Across Six Brook Trout (Salvelinus fontinalis) Strains in a Controlled Hatchery Setting

Growth and behaviour of fish in aquaculture and hatchery settings directly influence their market and stocking readiness. Despite their importance in recreational fisheries and high protein-to-energy content, the performance of brook trout in controlled settings is not well understood. This study compared six strains of brook trout (Assinica; Temiscamie, Horn Lake, Little Tupper; Domestic, Temiscamie × Domestic hybrids, and Windfall) stocked in the state of New York for growth, body composition, and surface feeding frequency to better understand their potential for aquaculture and fish hatchery programs. The Temiscamie × Domestic hybrids exhibited the highest specific growth rate in most trials, while Horn Lake strain often had the lowest. Length-to-weight relationships and dry weight (a proxy of lipid content) differed among strains, but not meaningfully. Surface feeding frequency differed greatly among strains but was only weakly related to specific growth rate. Surface feeding frequency was, however, related to the order of angling capture for 2 years in a small lined earthen pond, indicating strong potential for poststocking catchability. Our findings highlight the importance of evaluating strain-specific differences in growth, feeding behaviour, and catchability. These results also underscore the importance of tailoring strain selection with the specific goals of production, whether maximizing for market sale or for stocking into natural waters for angling.