Salmonid Redd Counts in the Saugeen River
Biotactic has been performing redd counts within the Saugeen River watershed since 2018. Surveys are conducted by trained staff in the spring during the Rainbow Trout spawning period, as well as in the fall during the Chinook Salmon spawning period. Counts are conducted within Otter Creek by wading and within the Saugeen River, upstream of the dam removal, by aerial drone videography. Such surveys are part of a long-term multi-component BACI study designed to measure the benefits conferred by removing the Truax Dam in Walkerton, Ontario for increasing fish biomass and production throughout the watershed. Seasonal count data is used to derive estimates of the amount of biomass production resulting from Salmonid reproduction.
Baseline phases of this study were conducted in Spring and Fall 2018 and Spring 2019 and the Truax Dam was removed in August 2019 as part of a fisheries offset and compensation project. The first post-dam-removal phase of this study was initiated in Fall 2019 and redd counts are scheduled to continue until 2026. To-date the number of Rainbow Trout redds observed in the Saugeen River (SR) and Otter Creek (OC) has increased by 2.1 to 7.2 times in the spring, while the number of Chinook Salmon redds has risen by 1.6 to 2.6 times in the fall since the removal of the Truax Dam. Previously an impounded headpond, spawning habitat can now be found within the newly created riffle-run habitat upstream of the former dam footprint within the Saugeen River, with as many as 31 redds counted from drone surveys conducted of this area alone.
Find additional details regarding the fisheries offset and compensation project here, the radiotelemetry component of this project here, the biomass electrofishing survey component here, and the videographic survey component here.
The most recent annual summary of all project component findings to-date (Summer 2024) can be found here.
A detailed summary of all radiotelemetry findings to 2022 can be found here. All radiotelemetry results were published in the scientific literature March 2024. A full free version of the publication can be found here.