Tsawwassen First Nation Launches Research on Sturgeon Deaths

The Tsawwassen First Nation is actively investigating a troubling increase in sturgeon deaths along the Fraser River in British Columbia. Earlier this month, a team recovered a sturgeon carcass measuring approximately 1.6 metres, one of many that have washed ashore recently. The team plans to freeze the body as part of a research initiative aimed at understanding the causes behind the mortality of these ancient fish.

Tracking and Understanding Sturgeon Mortality

Kelly Scott, a biologist with the Tsawwassen First Nation, describes sturgeons as “living fossils,” with a history dating back over 200 million years. The rise in mortality events is concerning, especially as residents near New Westminster report multiple sturgeon sightings floating downstream simultaneously. “We’ve received reports of four, five, or even six sturgeon at once within a single day,” Scott said, highlighting the urgency of the situation.

According to the British Columbia Ministry of Land, Water and Resource Stewardship, there has been a noticeable increase in sturgeon deaths this year, although the extent remains difficult to quantify. Since July, the province has recorded 71 sturgeon found dead, with 65 of these in the lower Fraser River. Alarmingly, 49 deaths have occurred in the past four weeks alone. In contrast, there were only 42 reported mortalities in the entire lower Fraser for 2024.

White sturgeon, known for their impressive size and longevity, can grow up to six metres in length and live for over 100 years. These fish hold cultural significance for First Nations, including the Tsawwassen, who historically harvested them for food and cultural practices. Although the harvest of sturgeon was prohibited in 1994, recreational fishing still occurs in the lower Fraser, raising questions about potential impacts from recent fishing activities.

Environmental Challenges and Research Initiatives

Environmental stressors are a key focus in the investigation. Climate change is contributing to rising water temperatures, which can adversely affect sturgeon health. Scott noted, “There are limited areas with large trees to provide shade, which means the fish lack the thermal refuge they once had.” Stressed fish are more vulnerable to mortality, particularly when caught in gill nets intended for other species.

In response to the alarming situation, the research team is working to gather data on sturgeon mortality. Their goal is to collect 20 carcasses for study, although many have been too decomposed for analysis. The team plans to fit recovered carcasses with telemetry trackers, allowing them to monitor sturgeon movements under various environmental conditions.

Scott emphasized the importance of understanding the habitats sturgeon occupy, particularly cooler areas that may support their survival. Collaboration with researchers at the University of British Columbia aims to leverage environmental genomics, using DNA and RNA samples to gain insights into sturgeon behavior and stress levels.

While the province has noted several potential contributing factors to sturgeon mortality, including disease and elevated summer water temperatures, it has found no direct evidence linking recent fishing activity to the deaths. A statement from Fisheries and Oceans Canada indicated that water temperatures in the Fraser River surpassed 20°C this summer, with risks increasing for sturgeon at temperatures above 18°C.

Sturgeon populations in British Columbia are protected under federal species-at-risk legislation. The Committee on the Status of Endangered Wildlife in Canada has assessed the lower Fraser population as threatened, although it is not yet formally listed for protection. Specific conservation licenses are required for catch-and-release fishing, and guidelines recommend minimizing stress on the fish during handling.

In 2021, British Columbia initiated a comprehensive plan to manage white sturgeon across the Fraser River basin, involving a steering committee composed of provincial and First Nations representatives, alongside input from the Fisheries Department. As the Tsawwassen First Nation continues its research, the focus remains on understanding and addressing the factors behind the alarming trend of sturgeon deaths.