NWT RESEARCH DATABASE

Regions: North Slave Region

Tags: environmental impact, biology, fish habitat, fish

Objective(s): To determine the potential effects of a ramping event (sudden shutdown of the power generation facility) on fish and fish habitat within the lower reaches of the La Martre River.

Project Description: Fieldwork is required to determine the potential effects of a ramping event (sudden shutdown of the power generation facility) on fish and fish habitat within the lower reaches of the La Martre River. This information would be added to the overall fish and fish habitat effects assessment and will identify potential mitigation measures, if required. Specific objectives of the field program include: 1. Identify fish habitat values and fish life-stage use of the braided side channels, vegetated benches and ephemeral areas of the lower La Martre River; 2. Identify relative abundance of fish use of the braided side channels, vegetated benches and ephemeral areas of the lower La Martre River in comparison to the mainstem channel; 3. Determine depth range of habitat use for each species and life-stage observed; and 4. Collect depth cross-sections within the braided channels in the Tailrace to 8 km Downstream River Section. Sampling of fish communities would be conducted in both the side channel habitats and mainstem channel. Fish sampling would be conducted by the following methods: • seine netting; • angling; • electroshocking; • minnow trapping (where possible); • underwater camera; and • snorkeling. The intent of the program is to evaluate the potential effect of lowering water levels downstream of the tailrace. Each fish caught will be identified to species and fork length and fish condition will be determined, and fish behavior and depth conditions at the point of capture will be recorded. The Community of Whati is approximately 23 km from the proposed project site. During the field program, two individuals from the community would be utilized for the Project. One member would be an experienced boat operator familiar with the lower reaches of the La Martre River. The second member would be familiar with the fisheries resources in the lower La Martre River and provide technical assistance during the field program. The project is being led by the Tli Cho Investment Corporation (TIC). TIC is in communication with the Community of Whati in regards to this project and would provide updated information on potential environmental effects as the project moves forward.