This thesis presents a study on the design and implementation of a Web-based Geographic Information Systems (GIS) application to support effective management of fish species at risk (FSAR) in Ontario, Canada. By using Internet and GIS technologies, a fish distribution management application was created and implemented for the Department of Fishery and Ocean Canada, Ontario Great lake Area (DFO-OGLA). The goal of the study is to implement a web-based fish species viewing and quering system that would allow users to obtain information about the FSAR data. The proposed WebGIS system not only includes common GIS mapping tools to navigate the map and geospatial data, but also provides specific geospatial search engine tools and fish species reporting tools. WebGIS provides an easy and inexpensive way for the biologists and environmental scientists to access FSAR information with web browsers.