| Citation |
Porter, M., M. Leslie-Gottschligg, K. Bryan, S. Chen, S. Casley, K. Connors, E. Jones, and L. Honka (2016) The Nass Area: Cumulative Pressures on Salmon Habitat (Technical Report), Pacific Salmon Foundation Vancouver, BC. |
| Abstract/Description or Keywords |
The Nass River watershed in northern British Columbia (BC) is one of the most important salmon watersheds in Canada. Known as the “River of Abundance,” in reference to its large runs of salmon and eulachon, the Nass covers an area of 20,700 km2 and flows 380 km from the Coast Mountains to Portland Inlet on the Pacific Ocean. The watersheds draining into Portland Canal and Observatory Inlet comprise an additional 6,000 km2 and, along with the Nass River watershed, make up the “Nass Area”. The Nass Area is home to five species of Pacific salmon (sockeye, coho, Chinook, chum, and pink), as well as steelhead, and provides extensive spawning and rearing habitat for multiple genetically and geographically distinct populations of wild salmon, called Conservation Units (CUs). In recent years, concerns have been raised regarding the vulnerability of salmon populations and their freshwater habitats to increasing natural and anthropogenic pressures in the region. Cumulative pressures from multiple land-use activities, in combination with changing environmental conditions, can alter landscape and watershed processes, disrupt fish habitats, and ultimately affect the survival, distribution, and abundance of wild salmon populations. Through direction from the Nisga’a Lisims Government, and in collaboration with Gitanyow, Gitxsan, and Lax Kw'alaams First Nations, DFO, BC Ministry of Environment, ESSA Technologies, and other local experts, the Pacific Salmon Foundation coordinated an assessment of landscape-scale pressures on salmon habitat in the Nass Area. This project employed a variety of habitat pressure, and habitat quantity and quality (vulnerability) indicators for assessment of lake and stream, habitats. Publicly available provincial-scale agency data layers available for the current exercise were supplemented through local datasets provided by regional First Nations. Specific project objectives were to: 1. Develop a synoptic overview of habitat pressures and resulting risk within freshwater habitats used by sockeye (lake and river types), Chinook, coho, pink, and chum salmon CUs across the Nass Area; and 2. Develop map-based habitat report cards for each of these Nass salmon species that: a. Summarize the relative extents and intensities of landscape pressures on freshwater habitats used by key life-history stages (migration, spawning, rearing) for each Nass salmon CU in relation to defined indicator benchmarks of concern (i.e., habitat risk status); b. Summarize the relative vulnerability of habitats used by the different life-history stages (migration, spawning, incubation, rearing) for Nass salmon CUs based on habitat quantity and quality characteristics that relate to inherent sensitivity and resilience to habitat impacts. This report describes the methods and results of the synoptic regional-scale overview of habitat pressures and vulnerabilities within defined zones of influence for eight lake sockeye, two river sockeye, two Chinook, three coho, three chum, and four pink CUs located in the Nass Area in northern BC. Using the best available data, a “report card” was generated for each Nass salmon CU. Collectively, the report cards provide a snapshot of the current risks to salmon habitat in the Nass Area from different human and environmental pressures. This type of coarse-scale assessment is useful for building a common understanding of the pressures on freshwater salmon habitats and for informing land-use planning decisions and developing strategies that mitigate risks to freshwater salmon habitat. |
