NWT RESEARCH DATABASE

Regions: Gwich'in Settlement Area

Tags: water quality, environmental impact, biology, hydrology, fish, bathymetry, benthic invertebrates, fisheries assessment, plankton

Project Description: While data collected during the Environmental Impact Assessment studies (carried out in conjunction with the proposed construction and operation of the Mackenzie Gas Pipeline) are relatively comprehensive in describing the major physical-chemical features of the aquatic environment, they are lacking in the descriptions of the biological features of these environments, and as a consequence, their sensitivity to various stressors. Accordingly, the aim of this study is to investigate fish and benthic invertebrate abundance and species composition at selected stream crossings of the proposed Mackenzie Gas Pipeline and lakes possibly affected by the pipeline. The information collected will serve as a baseline for assessing the potential impacts of Mackenzie Gas Project on lake and stream communities. Approximately four tributaries and seven lakes or ponds in the Gwich’in Settlement Area, which will likely be affected by the proposed Mackenzie Gas Pipeline route, will be sampled. On each tributary, sampling will be conducted at two locations: upstream of proposed stream crossing and downstream of proposed stream crossing. At each sampling location, a quantitative investigation of the fish community will be carried out by closing off a 100 m reach using seine nets and then by electroshocking the reach in three passes. Captured fish will be worked up (species determination, length and weight) and then released. Any fish killed during shocking will be kept for further laboratory analyses (stable isotope, ageing, etc.). A quantitative investigation of the aquatic invertebrate community will also be conducted at each sampling location through collection of three samples using a quantitative net sampler similar to a Surber sampler. Captured invertebrates will be preserved on site. In addition, water sampling will be carried out at each sampling location. Transportation to stream sampling locations will be by helicopter. Investigations at lakes or ponds will consist of mapping lake bathymetry using a GPS/depth sounding system. The following activities will be performed at deep sites: 1) water quality (temperature, DO, pH, conductivity, turbidity) measurements using a YSI multiprobe; 2) collection of plankton using a fine-mesh net; 3) collection of a water sample using a Niskin water bottle; and 4) collection of a sediment sample using an Eckman dredge. Near-shore activities will consist of collecting aquatic invertebrates using dip nets, and capturing forage fish using a seine net or by electroshocking. Transportation to lake sampling sites will be by float plane, and subsequently by a portable boat, which will be assembled and used on each lake. No base camps will be set up during the course of the fieldwork. The research team will operate out of Inuvik. The findings of this study will be shared with community organizations through project reports and possible community visits. Fieldwork will be conducted from August 2 to September 30, 2006 at the following locations: Unnamed Stream (RPR-058.6, 68.40086 133.30273); Unnamed Stream (RPR-070, 68.16473 132.98152); Travaillant River (RPR-097, 67.90868 132.19312); Unnamed Stream (RPR-108 67.80836 131.69374); Thunder River(RPR-141, 67.53466 130.84937); Unnamed Lake (RPR-108L, 67.80840, 131.69377); Caribou Lake (67.98249 132.93285); Hill Lake (67.97859 132.55142); Fish Trap Lake (67.94490 132.22014); Wood Bridge Lake (67.87591 132.16648); David Lake (67.82955, 132.14780); Crossing Creek Lake (67.81579 132.01921); Travaillant Lake (67.69184 131.78891).