NWT RESEARCH DATABASE

Tags: biology, fish habitat, fish

Objective(s): To conduct a fish tissue and fish habitat survey to support a water licence application.

Project Description: The main objective of the study is to implement a one-year environmental monitoring program to support a 2019 water licence application as well as associated regulatory requirements. Three studies will be done in 2019: a) Phase 6 Environmental Effects Monitoring (EEM) program; b) Fish tissue; and, c) Fish presence/absence, habitat survey and benthos sampling. The Ninespine Stickleback survey will be completed in late July/early August. For this survey, 100 young-of-the-year fish will be non-lethally sampled in each of the exposure areas (Baker Creek and Yellowknife Bay) and the reference area (Yellowknife River, in the area of Tartan Rapids and Horseshoe Island Bay). Fish will be released live back into the waterbody where they were captured. The following parameters will be assessed prior to release: abundance (catch-per-unit-effort), length, weight, and external condition (e.g. abnormalities, parasites). Ninespine Stickleback will be captured using small mesh seine nets, as well as dip nets. The Slimy Sculpin survey will be completed in September. For this survey, 30 adult males, 30 adult females and 30 juvenile fish will be lethally sampled in each of the exposure areas (Baker Creek and Yellowknife Bay) and the reference area (Yellowknife River, upstream of the bridge). These sample sizes are required to detect statistical differences between fish collected at the exposure and reference areas. The following parameters will be assessed: abundance (catch-per-unit-effort), length, weight, age, external condition (e.g. abnormalities, parasites), maturity, sex, internal condition (e.g. abnormalities, parasites, and tumours), gonad weight, gonad histology, and liver weight. Any young-of-the-year captured will be measured for length and weight prior to release back into the water body where they were captured. Slimy Sculpin will be captured using a backpack electrofisher, as well as small mesh seine nets, if required. Small-bodied fish may also be retained for tissue chemistry. Benthos will be sampled by artificial substrate (i.e., Hester-Dendy plates) and in situ grab samples (i.e., Ekman or PONAR). Artificial substrates will be installed in June and retrieved in September. Grab samples will be collected in September. During both fish and benthos surveys, supporting water quality and sediment quality samples will be collected. Seasonal water temperature will also be monitored throughout using remote temperature dataloggers. Fish will be captured in nets or other gear types. Community involvement is expected in the form of either or both Indigenous staff from Golder Associates or other community assistants and advisors, as available. Fishing gear will be used to document fish presence/absence including gill nets, seine nets, and backpack and boat electrofishing. Habitat information such as depth, substrate will be collected in the area as well. Field work will be completed by trained biologists and engineers who reside in Yellowknife and fishing will be done with the support of community members, if available and interested. The EEM study design and results will be provided to the Mackenzie Valley Land and Water Board for posting to the public registry. The Giant Mine Remediation Project also communicates regularly through the Giant Mine Advisory Committee which is composed of Yellowknife’s Dene First Nation members. As well the Giant Mine team communicates to the Giant Mine Working Group which includes North Slave Metis Alliance (NSMA) and YKDFN representatives, as well as interested community groups and other parties. The fieldwork for this study will be conducted from June 6, 2019 to December 31, 2019.