1. The Springbank dam structure is not a barrier to fish movement prior to dam closure each year and should remain this way after new gates are constructed.
2. Post-construction attraction efficiency of white sucker, shorthead redhorse and smallmouth bass should be statistically similar to pre-construction conditions. These values (reported as efficiency with 95 % confidence interval in parentheses) are:
90% (70% – 97%) for white sucker
80% (58% - 92%) for shorthead redhorse
95% (76% - 99%) for smallmouth bass
3. Post-construction passage efficiencies of white sucker, shorthead redhorse and smallmouth bass should not be statistically different from values determined under pre-construction conditions in 2006. These values (reported as efficiency with 95 % confidence interval in parentheses) are:
94% (74% - 99%) for white sucker
94% (74% - 99%) for shorthead redhorse
89% (69% - 97%) for smallmouth bass
4. Fish movement should not be delayed to the point where successful migration and reproduction are compromised. Most fish rapidly approached and swam upstream through the dam structure in 2006. The amount of time required for dam passage should not be statistically different between pre-construction and post-construction conditions. The mean time (± standard deviation) required for each species to pass the Springbank dam was:
5.2 ± 7.4 minutes for white sucker
3.5 ± 2.6 minutes for shorthead redhorse
16.7 ± 22.1 minutes for smallmouth bass
5. Post-construction attraction efficiency and passage efficiency should be monitored for a minimum of two years, and maximum 5 years after construction using radio telemetry emulating 2006 baseline data collection methodology. As with all scientific research, the study would benefit from more species, larger sample sizes and a multi-year monitoring program. Additional opportunities to monitor additional species or enhanced sample sizes may become available through partnerships with other agencies that may be interested in other fisheries objectives such as development of a Fisheries Management Plan that will greatly benefit the Thames River.
Four hydraulic gate structures were installed in 2007. The City of London commissioned a study to determine whether fish movement at the Springbank Dam (Thames River, Ontario) had been affected. The purpose of this work was to telemetrically assess fish movement and behaviour at the dam after construction of the new dam gates and to compare post-construction fish-movement data with pre-construction baseline data collected in 2006. Three years of post-construction data were collected.
