Freshwater Fish Populations in Eastern Ontario Benefit from Long Standing Protected Areas

Research has identified numerous conservation benefits attributed to the use of protected areas (PAs), yet the effectiveness of spatial protection in freshwater systems (FPAs) remains unclear. In this thesis, I assessed multiple longstanding (>70 years active) intra-lake FPAs within the Rideau Waterway system (Ontario, Canada) to evaluate their potential conservation value. Initially, these FPAs were established to protect exploited populations of largemouth bass (Micropterus salmoides). However, since their inception, there has been no empirical data collected to evaluate their effectiveness for protecting bass or the broader fish community. To address this, I conducted a series of comparative assessments to evaluate how these FPAs influence largemouth bass space-use dynamics, capture vulnerability, and physiology. I also evaluated potential indirect benefits at the community level through measuring differences in fish community structuring between FPA and non-protected areas. The FPAs evaluated strongly benefitted largemouth bass through increased population densities within the protected area boundaries. These FPAs also indirectly benefitted several non-target fish species by supporting increased population densities and species richness, with evidence of fish spillover occurring into adjacent non-protected waters. Acoustic telemetry data revealed that largemouth bass displayed high occupancy, particularly during the spring-summer seasons, within a designated FPA. This space-use behaviour was repeatable across years, and also positively correlated to fish size, with larger individuals utilizing the FPA more extensively relative to smaller individuals. Beyond serving as a mechanism to benefit fish community structure, FPAs were also found to protect key phenotypes linked to angling vulnerability in largemouth bass, suggesting a potential for FPAs to provide evolutionary-enlightened benefits. The results presented in this dissertation are novel and showcase a host of biological benefits associated with the use of FPAs. Moreover, the consistency in results across all FPAs suggests an effective and transferable resource management tool, which may help to enhance freshwater conservation efforts. As challenges facing freshwater systems continue to mount, the need for effective management strategies has never been greater. As such, the data presented here provides a stronger understanding of how FPAs can offset anthropogenic impacts on freshwater fish communities, which may have far-reaching implications for contemporary fisheries management practices.