Assessment of lake trout populations within the Inuvialuit settlement region of Northwest Territories and Yukon, 2014 - 2015

Fish are an important subsistence resource to residents of the Inuvialuit Settlement Region (ISR). While many lakes and rivers exist in the ISR, access can be seasonally limited due to changes on the landscape (i.e., winter snow and ice cover vs. summer open water). Due to these limitations, waterbodies within the ISR are used at various times of year. To allow for year-round access via ground travel between Inuvik and Tuktoyaktuk, the Inuvik-Tuktoyaktuk Highway (ITH) was constructed. This highway has also created the opportunity for year-round access to many lakes and rivers in close proximity to the road, creating the potential for increased fishing pressure. One species that is highly sought after in the region is Lake Trout (Salvelinus namaycush). Lake Trout are a long-lived and late-maturing species that reside in cold, low-productivity lakes and are vulnerable to overharvest. To better understand Lake Trout ecology within the region and collect baseline data prior to the ITH completion, we sampled six lakes believed to hold Lake Trout within the ISR. To accomplish this, we set short-set experimental gill nets along the shoreline to describe species composition, key biological metrics, catch rates, and to collect tissue samples for additional projects. In addition, lake bathymetry and water properties were assessed at all locations. Key findings from the study indicate that 1) Lake Trout spawn at the end of August and into early September, 2) spawning typically occurs on the leeward side of lakes (i.e., south to southeastern end for this region) on cobble shoals, 3) during spawning, Lake Trout aggregate in high numbers on spawning shoals, and 4) Lake Trout were found in all but Parsons Lake. Moving forward with management of fisheries along the ITH, local management agencies should recognize that Lake Trout aggregate in large numbers during spawning and are highly vulnerable to nets and angling during late summer. If overharvest becomes a concern, management action should be taken to protect this locally important resource.