A Pond Evaluation of Habituation as a Means to Reduce Initial Mortality Associated with Poststocking Predation of Hatchery-Reared Largemouth Bass

Abstract

We investigated whether habituation (i.e., allowing fish to become accustomed to their new environment) and habitat complexity affected poststocking predation of hatchery-reared fingerling Florida largemouth bass Micropterus salmoides floridanus stocked in research ponds containing high densities of predators. We found that in open-water habitat, habituation for 60 min before release significantly (|t ₄₄| ≥ 2.13; P ≤ 0.039) reduced predation. In the presence of complex habitat (i.e., stem density > 250 stems/m²), overall predation was reduced but habituation failed to further reduce predation (|t ₄₄| ≥ 0.13; P ≤ 0.899). Habituation appears to be a feasible method for reducing predation at release locations with little to no structurally complex habitat and high predator densities.