Pacific Salmon Explorer Spawning Zones of Influence

This dataset displays the spawning zone of influence (ZOI) for all salmon Conservation Units (CUs) assessed in the Pacific Salmon Explorer. A spawning zone of influence (ZOI) is the area of land that drains into the spawning habitat of a specific salmon CU. Methods to delineate spawning ZOIs vary by species and region (refer to Appendix 5 in Methods for Assessing Status and Trends in Pacific Salmon Conservation Units and their Freshwater Habitats) but the spawning zone of influence (ZOI) is most commonly defined as the 1:20,000 Freshwater Atlas assessment watersheds within the CU boundary where species-specific spawning is known to occur.