Date of Award


Publication Type

Master Thesis

Degree Name



Biological Sciences

First Advisor

MacIsaac, Hugh,


Biology, Ecology.




This study employed a doubly-constrained gravity model to track the dispersal, and hence assess the risk of invasion, of the spiny waterflea Bythotrephes longimanus in inland lakes in Ontario. The analysis required detailed information on individual vector movements. It was initially hypothesized that waterfowl could be involved in the dispersal of B. longimanus between lakes. However, invaded lakes were found to be significantly closer to major highways than non-invaded lakes (t = 3.957, n = 175, p < 0.001), suggesting human-mediated transport of the species was more likely. Thus, information used in the gravity analysis was acquired by conducting a survey that assessed individual human-based vector movements in Ontario. Survey and gravity results were then input into a GIS, which allowed for an extensive spatial analysis of vector patterns. Two models were conducted: one that backcasted the past invasion dynamics of B. longimanus in Ontario, and one that forecasted a possible future distribution based on vector patterns. (Abstract shortened by UMI.) Source: Masters Abstracts International, Volume: 40-06, page: 1460. Adviser: Hugh MacIsaac. Thesis (M.Sc.)--University of Windsor (Canada), 2001.