In 2009, DFO defined 12 marine bioregions across the three oceans bordering Canada to support its marine planning efforts, such as the establishment of networks of marine protected areas. However, these bioregions cover vast areas and exhibit significant ecological heterogeneity, especially along the coasts. Yet, this heterogeneity in coastal ecosystems often needs to be considered at the local scale, particularly for management and conservation purposes.

The objective of this exercise is to subdivide the Estuary and Gulf of St. Lawrence (EGSL) bioregion for the province of Quebec into coastal sub-bioregions to better reflect local and regional coastal characteristics. The coastal classification presented in this report is based on the integration of four existing classification systems for the EGSL, which were not specifically designed for classifying coastal ecosystems. Integrating these classification systems into a single approach allowed us to define 13 coastal sub-bioregions for the EGSL. Data presented here are the limit of the 13 ecoregions made from this work.

A technical report is available for more details. See supporting documents:Gendreau, Y., Narancic, B. et Bourassa, M-N. 2025. Classification écologique du territoire côtier de l’estuaire et du golfe du Saint-Laurent au Québec. Rapp. tech. can. sci. halieut. aquat. 0000 :v + 22p.