Gizzard Shad Incident at Bruce A – March 2025

Press Release

Mar 21, 2025

A significant Gizzard Shad event has been ongoing at Bruce A since late January, resulting in large-scale fish impingement at the pumphouses. The shad are attracted to the warm water from Bruce Power’s discharge channels and become trapped in the intake system. This has led to up to 3.5 million to 4.5 million Gizzard Shad being impinged at Bruce A. While Gizzard Shad are naturally sensitive to cold water temperatures and can experience mass die-offs in the wild, this event raises concerns about the impacts of the artificial environment for aquatic life at the Bruce site.

Underwater camera footage has identified large schools of Gizzard Shad approximately 1 km northwest of the Bruce A site. By March 3, numbers had stabilized at approximately 500 fish per day and continue to trend downward. Additionally, two grass carp, an invasive species, have been sighted, and the potential impacts of their presence are being investigated.

The Joint Chiefs and Councils are prioritizing the investigation of potential impacts to aquatic life due to the artificial environment at the Bruce site, and potential strategies to address those impacts. Over the last month, both SON Chiefs, along with members of Council and EO staff, met with federal agencies in Ottawa to discuss how Canada, as our treaty partner and as a regulator, will work with us to strengthen environmental protection.

The Saugeen Ojibway Nation Environment Office has been closely monitoring the situation to assess the immediate and potential long-term environmental impacts, as well as the current mitigation efforts. Large numbers of bald eagles and dead birds along the shoreline have been recorded. The Environment Office will continue to monitor and provide oversight to these efforts, while providing recommendations for mitigation strategies. Bruce Power has committed to share data with SON so that the causes of the event can be better understood and the effectiveness of mitigation measures can be assessed. Efforts to address the situation are being supported by our Aquatic Ecologist, Coastal Waters Monitoring Program and the Energy Department.

Membership will be kept updated as more information becomes available. The data will be reviewed and researched to better understand how to prevent similar events, and discussions with Bruce Power on long-term solutions, including intake protection improvements, will continue. SON has emphasized the need for effective strategies to reduce fish impingement at its source, including possible modifications to intake and recirculation structures.

The SON Joint Council, with the support of the Environment Office, is committed to ensuring that SON’s environmental rights and interests are upheld throughout this process.

ILR5