Macus Ong

Okanagan Nation Alliance, 101-3535 Old Okanagan Highway, Westbank, BC V4T3L7

sc̓win (Sockeye Salmon) (Oncorhynchus nerka) in the Okanagan Basin faced a perilous decline due to a multitude of factors, including overfishing, hydro dams, habitat alteration in Canada, and the construction of impassable dams that obstructed access to critical spawning grounds. The McIntyre Dam, erected in 1954, represented a significant barrier blocking all upstream migration. By the mid-1990s, the Sockeye Salmon run had dwindled to fewer than 5,000 fish, raising alarms about the species' survival in the region. The Skaha Lake Sockeye Reintroduction Program, initiated in 2003, therefore, aimed to restore Sockeye populations in t̕uʔcin (Skaha Lake) and nk’mip (Osoyoos Lake), and presently kłusxnitkʷ (Okanagan Lake), all situated within the Okanagan Basin in the Southern Interior of British Columbia. Collaborative efforts involving the Okanagan Nation Alliance (ONA), Fisheries and Oceans Canada (DFO), Grant and Chelan Public Utility Districts, Columbia River Inter-Tribal Fish Commission (CRITFC), and the Colville Confederated Tribes have been instrumental in addressing limiting factors affecting Sockeye Salmon abundance. The program utilizes passive integrated transponder (PIT) and acoustic tagging technologies to track adult Sockeye Salmon during their upstream migration from Wells Dam to their spawning grounds in the Okanagan Basin. Additionally, Sockeye smolts originating from t̕uʔcin and nk’mip are tagged for comparative survival studies (CSS) beyond the basin. PIT tagging began in 2012 and continues to the present. Between 2012 and 2023, a significant number of Sockeye smolts were PIT tagged, with numbers ranging from 534 in 2012 to 7,435 in 2022. In 2023, 5,463 hatchery raised Sockeye fry were thermal marked, PIT tagged, and released into Equesis (also known as Six Mile) Creek, a tributary of Okanagan Lake, marking the monumental first year of Sockeye fry tagging for kłusxnitkʷ amongst many tagging programs within the ONA kł cp̓əlk̓ stim̓ (Cause to Come Back) hatchery. Fishing methods employed include rotary screw traps and purse seines for t̕uʔcin outmigrants, and only purse seining smolts out-migrating from nk’mip. These smolts are tagged before release. The primary objectives of PIT tagging within this program are to monitor and investigate outmigration patterns, travel times, and survival rates of Okanagan Sockeye smolts to Bonneville Dam and the estuary in the Lower Columbia River. Furthermore, the program aims to scrutinize factors that influence the abundance of returning adult Sockeye Salmon. The potentials of the PIT tagging program within the ONA encompass modeling and forecasting migration of ONA-tagged Sockeye, exploring in-lake survival of the Sockeye population, and gaining insights into population distribution. Preliminary data shows outmigration occurs between April and May. This comprehensive approach contributes valuable data for the conservation and management, especially homing migration, of Okanagan Sockeye Salmon populations in the Okanagan Basin that will ultimately contribute to harvest and fishery.