NWT RESEARCH DATABASE

Regions: South Slave Region

Tags: environmental impact, biology, fisheries assessment, industrial development, aquatic environment, hydroelectric station

Objective(s): The objective of the proposed work is to collect information on the fish community and fish habitat present in Trudel Creek, and identify the possible positive and negative impacts of reducing flow into the creek if the Taltson Hydro Project is expanded.

Project Description: The objective of the proposed work is to collect information on the fish community and fish habitat present in Trudel Creek, and identify the possible positive and negative impacts of reducing flow into the creek if the Taltson Hydro Project is expanded. The field survey of the fish habitat and community of Trudel Creek and a section of the Taltson River will take place in spring, with the possibility of a second trip to collect additional information in the summer. Rescan scientists and field assistants will fly into Fort Smith and then be transported to the Twin Gorges Camp (60° 25' 02" N 111° 24' 01" W) either by plane or helicopter. Fish community and habitat surveys will be carried out from an inflatable zodiac equipped with a motor brought from Vancouver by Rescan. Habitat surveys will be carried out using a range of measuring, photographic and GPS equipment. Fish community surveys will predominantly entail the use of gillnets with varying mesh size. Other potential alternative methods will include beach seines, minnow traps, electrofishing, angling and snorkelling. The species and numbers of fish that will be captured during the survey is unknown, but gillnet sets will remain short (approximately 1 hour) to minimize fish mortality. Mortality is not expected to occur using the other methods. A fish community survey of Trudel Creek conducted by Rescan in 2006 resulted in the capture of lake whitefish (Coregonus clupeaformis), northern pike (Esox lucius), walleye (Sander vitreus), longnose sucker (Catostomus catostomus) and white sucker (Catostomus commersonii). Other species that may potentially be captured, due to their presence in nearby lakes or the Taltson River, include: lake trout (Salvelinus namaycush), trout-perch (Percopsis omiscomaycus), burbot (Lota lota), cisco (Coregonus artedii) and lake chub (Couesius plumbeus). Trudel Creek is unlikely to contain any fish species not listed above. A final report based on the results of this study will be made publicly available by Northwest Territories Energy Corporation. The study will be conducted from April 11 to December 31, 2007 at Trudel Creek (start: 60° 24' 54" N 111° 25' 20" W; end: 60° 28' 07" North; 111° 17' 44") and Taltson River (start: 61° 07' 35" N 112° 36' 07" W; end: 61° 03' 13" N 112° 32' 58" W).