Date of Award


Publication Type

Master Thesis

Degree Name



Earth and Environmental Sciences

First Advisor

Daniel Heath


Biological sciences



Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.


The recent upstream colonization of Great Lakes tributaries by round goby, Neogobius melanostomus, provides an opportunity to identify dispersal mechanisms and examine invasion dynamics associated with successful colonization of a novel aquatic environment. Genetic analyses identified a stratified dispersal strategy associated with upstream colonization. Genetic diversity was maintained during colonization by natural dispersal suggesting founder effects may be mitigated and adaptation may facilitate river colonization. Swimming performance analyses indicates that the uni-directional and high flow of rivers does not limit range expansion. However, morphological differences between lake and river populations suggest that dispersal is not a random diffusion of fish from the lake. Continued expansion and population persistence will increase the impact of this highly invasive species. Future research should monitor river invasion front populations for changes in dispersal and rate of colonization.