Foraging Dynamics of a Domesticated Strain of Brook Trout

Abstract

AbstractThe Brook Trout Salvelinus fontinalis is an economically important salmonid that has been stocked worldwide. Because of the difficulty of culturing southern Brook Trout, domesticated northern Brook Trout have been stocked throughout the southeastern United States. Little research has been dedicated to understanding the foraging dynamics of various forms of the species that occur within southeastern streams. Given that water velocity has been shown to have a strong influence on habitat selection and prey capture in drift feeders, we examined the effects of water velocity, fish size, days in captivity, dominance status, and size rank on prey capture success, holding velocity, and reactive distance for domesticated northern‐strain Brook Trout. Prey capture success declined with increasing velocities (10–50 cm/s), holding velocity was positively related to water velocity, and dominant individuals captured more prey than subordinates. Reactive distances were not strongly or consistently affected by any treatment variables. Compared with recent studies on southern Brook Trout, there were few differences between the strains in their foraging behavior, suggesting that our results apply to the species generally. Various forms of the species should exhibit high prey capture success in velocities up to 30 cm/s.