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 through a combination of wading and 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 to-date staff have observed a significant increase in the number of redds produced upstream of the dam footprint. Redd counts are scheduled to continue until 2026.


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.

A summary of all project findings to-date can be found here.

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