Federal Whales Initiative – Freshwater and sediment data (Pacific Region)

The Initiative to Protect and Recover Endangered Whale Populations from anthropogenic threats (aka Federal Whales Initiative) was announced on June 22, 2018, by Fisheries and Oceans Canada (DFO), Transport Canada (TC) and Environment and Climate Change Canada (ECCC). The first iteration of this initiative, Whales Initiative 1.0 (WI1.0), spanned from 2018 – 2023. WI1.0 focused on three endangered whale species listed in the federal Species at Risk Act (SARA) including the Southern Resident Killer Whales (SRKW) (Orcinus orca), as well as their primary prey, Chinook salmon (Oncorhynchus tshawytscha). Threats identified under the 2018 SARA recovery strategy for Northern and Southern Resident Killer Whales include several anthropogenic factors such as acoustic and physical disturbances, prey availability and quality, and environmental contaminants (“Recovery Strategy for the Northern and Southern Resident Killer Whales (Orcinus orca) in Canada” https://www.canada.ca/en/environment-climate-change/services/species-risk-public-registry/recovery-strategies/northern-southern-killer-whales-2018.html ). Whales Initiative 2.0 (WI2.0) spanned from the fall of 2023 – spring 2026, with water and sediment sampling continuing at reduced frequencies.

SRKW critical habitat covers a large portion of the Salish Sea off the Southwest coast of British Columbia. The Fraser River represents the largest source of freshwater discharge into the Salish Sea as well as the primary migratory pathway for Chinook salmon during the freshwater habitat component of their life cycle. SRKW and their prey are at risk from a range of contaminants that may be present in the Fraser River and smaller freshwater systems draining into the Salish Sea. Contaminants of concern (CoCs) are typically persistent in the environment, with the potential to bioaccumulate and biomagnify in the food web. These contaminants can also reduce salmon survival by making them more susceptible to disease, which in turn means less prey abundance for the killer whales. Exposure to certain toxic contaminants can also reduce immunity and cause reproductive disruption in the whales (Garrett and Ross, 2010). Understanding the presence and levels of CoCs in these important freshwater systems is critical for determining their potential impact on SRKW and their prey species.

Freshwater and sediment sampling conducted as a part of WI1.0 and WI2.0 sought to identify concentration and frequency of CoCs. The list of sampling sites and the CoCs analysed were expanded/modified as the program developed. Freshwater sites were sampled multiple times through the year while sediment sites were sampled annually during seasonal low water/low flow periods following the annual freshet, allowing for sediment deposition (accumulation) in the streams before the next freshet period. There are gaps in the datasets from COVID-19, forest fires and floods.

Sampling sites included in the datasets are located primarily in the Fraser River watershed (Fraser River at Hope, Fraser River at Gravesend Reach) and key tributaries to the Fraser River (Thompson River and Harrison River) and in smaller rivers that discharge directly to the Salish Sea (Serpentine River and Nicomekl River). Site selection in WI2.0, includes a greater number of smaller freshwater systems, including Columbia River chinook habitat with the addition of a site in Osoyoos Lake.