Thesis - Open Access
Master of Science (MS)
Natural Resource Management
Black Bullheads, Food Habits, Gizzard Shad
Managing fisheries requires balancing predators and prey. Prey stockings are often used when food sources may be limiting to support fish communities with multiple predators. Stocking of prey often results in increased predator size and could potentially lead to the consumption of nuisance species such as Black Bullheads Ameiurus melas. Gizzard Shad Dorosoma cepedianum are an often-stocked prey species and have been recently stocked into several small impoundments across South Dakota. One of the focuses of this study was to document the contribution of age-0 Gizzard Shad to predator fish food habits and growth. Gizzard Shad consumption varied between impoundments and predators, with shad primarily being consumed in western impoundments. Gizzard Shad made up to 50% of Black Crappie Pomoxis nigromaculatus, Largemouth Bass Micropterus salmoides and Walleye Sander vitreus. The absence of Gizzard Shad from several predator food habits resulted in either a reduced growth or little to no effect during bioenergetic simulations. Though Gizzard Shad were important to several predator food habits, the presence or absence does not seem to impact the growth of predators. Even with little impact on predator growth Black Bullheads were vulnerable to predation by these predators. However, relatively few bullheads were consumed by predators. The introduction of Gizzard Shad into impoundments seems to have limited impacts on both predator species and in turn no effect on the biological control of Black Bullheads. There is potential that future introductions will have similar results and that predator fish may not be enhanced and that there will be no biological control of Black Bullheads. There is still unknown information about the effects of Gizzard Shad introductions within these small impoundments and future research should focus on how other species are impacted. Additionally, future research should examine under what conditions Black Bullheads are selected for as prey.
Number of Pages
South Dakota State University
In Copyright - Educational Use Permitted
Vanderbush, Branson, "Direct and Indirect Effects of Recent Gizzard Shad Introductions in Four South Dakota Small Impoundments" (2019). Electronic Theses and Dissertations. 3659.