NatureWatch Canada, a citizen science program, collects and analyses data pertaining to plant phenology, frog species and ice coverage over water bodies in Canada to monitor trends through time and space in relation to climate change. An important question is whether this database is currently usable to infer environmental changes through space and time. This thesis presents a metadata analysis of the Nature Watch database in order to identify the spatial validity, quality, reliability and usability of the current data. We first explore citizen science through a review of the literature, followed by a detailed analysis of the content of the database. We also produce an example Newsletter for each module to illustrate some of the current trends in the data. The Frogwatch Newsletter shows how weather conditions in 2001 may have favored a population spurt of Leopard frogs resulting from more spawning ponds essential for this species. Next the Plantwatch Newsletter reveals that an increase in Aspen poplar and Prairie crocus in 2002 may have been due to fires during the preceding years. Lastly, the Icewatch Newsletter shows how ice formation, but not melt, reveals a clear trend of occurring 17 days later over the last 100 years with a stronger increase starting in the sixties for Western Ontario. In summary, this thesis presents a detailed metadata analysis of the Naturewatch database in order to provide recommendations for its improvement in the future. Improving programs like Naturewatch Canada is important to monitoring climate and ecological changes that could be applied throughout the Canadian North which are not currently well represented in this database.