NWT RESEARCH DATABASE

Regions: South Slave Region

Tags: biology, climate change, fish, fish health, transboundary, Slave River, biomonitoring

Objective(s): To collect additional samples for fish health and fish contaminant levels, and to track their status over time to assess ecosystem health and provide an indication of change or stress in the environment.

Project Description: This licence has been issued for the scientific research application No.5339. The objectives of this project are to collect additional samples for fish health and fish contaminant levels, and to track their status over time to assess ecosystem health and provide an indication of change or stress in the environment. The research team will be sampling the same species of fish that were investigated in past studies in the Slave River (burbot, lake whitefish, walleye, northern pike) as well as species included in Oil Sands Monitoring program (white sucker and trout-perch). The timing and method of sampling fish will vary according to spawning seasons, community fishing practices, and historic sampling programs. The research team will sample whitefish, walleye, northern pike, and white sucker in the Slave River at Fort Smith and in the Slave River delta (SRD). Target sample sizes will be 20 adult males and 20 adult females collected by gillnet and supplemented by angling if necessary for each species. The lengths and weights of these fish will be measured and tissues will be collected for contaminant analyses. The research team will also sample trout-perch, using electrofishing equipment or seining and targeting 20 adult males and 20 adult females in the Slave River at Fort Smith and in the Slave River delta. The team will sample burbot under ice by jiggling or set lines near Ft. Smith and sampled for contaminants, targeting 20 males and 20 females. White sucker and walleye will be sampled during their respective spawning runs in the Slave River near the mouth of the Salt River. The research team expects to repeat this sampling work every 5 years to monitor change over time. Trout-perch, and potentially slimy sculpin, spottail shiner or emerald shiner will also be targeted in 2022, 2023, and 2024 to establish a monitoring baseline. Small-bodied fish will be collected in summer and/or fall 2022, and potentially monthly during open-water in 2023 and 2024 by minnow traps, seining, and/or electrofishing and sampled for the same endpoints as large-bodied fish. Fish growth and gonads develop rapidly throughout the year, therefore monthly sampling would help determine the ideal time to monitor fish health. While collecting small-bodied fish, benthic invertebrate samples will be collected using D-frame nets and kick-sampling for stable isotope analysis. Per previous research, communications with community members, and ongoing studies by Smith’s Landing First Nation, large-bodied fish are highly mobile between Great Slave Lake, Slave River Delta, and Slave River at Ft. Smith. Stable isotopes will be used as ecological tracers to improve understanding of where fish are feeding and spending time, which, in turn, will improve understanding of potential contaminant exposure/stressor pathways for fish. A meeting is scheduled to occur in late June for community partners to discuss results from large-bodied fish sampling, and to discuss the work planned. During the 2019 SRD planning meetings, members told the team that in addition to in-person meetings and reports, posters are effective communication tools. The research team are currently preparing posters, and planning to hold community meetings to share results. Additionally, technical and plain language reports detailing the findings of the monitoring program will be shared when completed. The fieldwork for this study will be conducted from May 1, 2023 to December 31, 2023.