Hatchery Effects On Florida Largemouth Bass Micropterus Salmoides Floridanus Resource Allocation, Behavior and Post-Release Survival

Hatchery rearing results in domesticated phenotypes that can affect the organism’s physiology and behavior in ways that are detrimental to fitness in the wild. Understanding how domestication effects arise and how these phenotypic changes influence survival after release are of great importance to enhancement programs. We tested whether the provision of limited and irregular feeding results in more wild-like resource allocation, behavior and survival under predation in hatchery fish. We characterized the metabolism, activity, boldness and sociability of juvenile pellet-reared largemouth bass of different feed experience and juvenile wild bass. Bass were released into 0.25acre ponds stocked with predators and forage. After 5 weeks the surviving fish were collected and behavior and allocation were re-characterized. Our results have shown that reduced and irregular food provisioning produced hatchery fish that more closely resembled wild-fish with respect to standard metabolism and behavior. Thus, the manipulation of feeding regimes can serve as a simple and economical mean to producing more wild-like fish relative to other conditioning practices. Despite the phenotypic differences among hatchery treatments, we did not find differences in survival. Interestingly, we found differences in the post-stocking growth of hatchery-reared juveniles suggesting differences in long term survival may exist.