Conservation Unit Habitat Report Cards: Quantifying Risk to Salmon Habitat in Bc's Skeena Region

BC’s Skeena River provides extensive freshwater habitats for five salmon species, steelhead, and 30 other fish species. This includes 53 evolutionarily distinct salmon Conservation Units (CUs). The Skeena has to date avoided much of the development pressure that has compromised fish habitats in other large watersheds. However, there are exceptions (e.g. areas of extensive logging) where habitat deterioration has harmed fish populations, while numerous development proposals (pipelines, mines, highways, etc.) and other landscape stressors (e.g. mountain pine beetle, climate change) present a growing threat to Skeena salmon habitats. ESSA Technologies under contract to the Pacific Salmon Foundation (PSF) undertook quantitative GIS-based assessments of the relative extent/intensity of regional watershed-scale pressures impacting freshwater habitats used by Skeena salmon life-history stages (migration, spawning, incubation,  rearing). The project provided a broad-level synoptic overview of current stresses on Skeena salmon freshwater habitats. Information was summarized in CU habitat “report cards” that reflect the current and future risk/vulnerability of Skeena salmon species CUs to habitat degradation. Combined with concurrent work by ESSA/PSF on the status of Skeena salmon populations (reported in concise CU population “snapshots”) the information provides a useful frame for assessing varying risks of cumulative effects on salmon in the Skeena River drainage.