Hydrobiologia https://doi.org/10.1007/s10750-020-04371-2 (0123456789().,-volV)( 0123456789().,-volV) PERSPECTIVES ON SUSTAINABLE HYDRO-POWER Review Paper Using an integrative research approach to improve fish migrations in regulated rivers: a case study on Pacific Salmon in the Seton River, Canada Nolan N. Bett . Scott G. Hinch . Arthur L. Bass . Douglas C. Braun . Nicholas J. Burnett . Matthew T. Casselman . Steven J. Cooke . S. Matthew Drenner . Ahmed Gelchu . William L. Harrower . Roxx Ledoux . Andrew G. Lotto . Collin T. Middleton . Vanessa Minke-Martin . David A. Patterson . Wenming Zhang . David Z. Zhu Received: 16 March 2020 / Revised: 15 July 2020 / Accepted: 28 July 2020 Ó Springer Nature Switzerland AG 2020 Abstract Many of the world’s rivers are dammed, allowing for applied research that can advance our altering the physiology, behaviour, ecology and sur- understanding of the biology of migratory fish as well vival of fish. Integrative research has the potential to as our ability to manage them. Through the integration improve our understanding of these impacts and could of multiple research approaches (i.e. biotelemetry, enable environmental managers to develop effective behavioural tests, physiological and molecular analy- solutions for population conservation. Such ses, and hydraulic monitoring), we characterized the approaches, however, are not yet prevalent. We use effects of natal water dilution and dam flow releases on a case study on Pacific salmon (Oncorhynchus spp.) in upstream navigation, passage success and post-pas- British Columbia, Canada, to demonstrate how regu- sage survival of returning adult salmon. Our findings lated rivers may be used as experimental systems, confirmed previously established operational guideli- nes for natal water dilution and informed the adoption of new operational conditions for dam flow releases, Guest editors: Ingeborg P. Helland, Michael Power, Eduardo G. Martins & Knut Alfredsen / Perspectives on the providing an example of the successful application of environmental implications of sustainable hydro-power N. N. Bett (&) Á S. G. Hinch Á A. L. Bass Á N. J. Burnett Á S. J. Cooke D. C. Braun Á N. J. Burnett Á M. T. Casselman Á Fish Ecology and Conservation Physiology Laboratory, S. M. Drenner Á W. L. Harrower Á A. G. Lotto Á Department of Biology and Institute of Environmental and C. T. Middleton Á V. Minke-Martin Interdisciplinary Science, Carleton University, Ottawa, Pacific Salmon Ecology and Conservation Laboratory, ON K1S 5B6, Canada Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada N. J. Burnett Á A. Gelchu e-mail: [email protected] BC Hydro, Vancouver, BC V6B 5R3, Canada D. C. Braun M. T. Casselman InStream Fisheries Research Inc., Vancouver, BC Hydro Environment Water Program, Fish and Aquatic BC V5M 4V8, Canada Issues, 6911 Southpoint Drive, Burnaby, BC V3N 4X8, Canada D. C. Braun Á D. A. Patterson Fisheries and Oceans Canada, Cooperative Resource S. M. Drenner Management Institute, School of Resource and Stillwater Sciences, Los Angeles, CA 90013, USA Environmental Management, Simon Fraser University, Burnaby, BC V5A 1S6, Canada S. M. Drenner Marine Science Institute, University of California Santa Barbara, Santa Barbara, CA 93106, USA 123 Hydrobiologia integrative research to the management of a fisheries The variety and complexity of ecological responses resource in a regulated river. We encourage research- to dams make management-relevant research in reg- ers to consider using an experimental approach that ulated rivers especially challenging (Power et al., integrates multiple research disciplines to inform 1996). The effects of dam infrastructure and operation science-based management action. on river ecosystems can be wide-ranging and are influenced by the geomorphology, environmental Keywords Fish passage Á Fishway Á Regulated conditions and biotic assemblages that are unique to rivers Á Migratory fish Á Freshwater conservation Á each system. Researchers and natural resource man- Integrated approach agers have repeatedly called upon a more integrated approach to address the complex issues facing sustainable freshwater management (Brett, 1957; Naiman et al., 1995; Alcamo et al., 2008), but this Introduction approach is often not put into practice. Traditional approaches that attempt to compartmentalize prob- The number of dams on the world’s largest rivers is lems are outmoded as they fail to yield the level of continuing to rise (Zarfl et al., 2015), and the majority nuanced and integrated understanding that is nee- of large rivers are no longer free-flowing (Grill et al., ded to truly solve complex problems (Dick et al., 2019). This phenomenon is truly global—dams can be 2016). Murchie et al. (2008) conducted a comprehen- found on every continent aside from Antarctica and sive review of articles studying the effects of river are proliferating in many of the world’s most biodi- regulation on fish, and while the authors found verse basins, such as the Amazon, Congo and Mekong consensus that flow modification does indeed influ- (Winemiller et al., 2016). Flow modification can have ence fish and fish habitat, they also identified persistent a significant impact on geomorphology (Petts and limitations to methodological approaches that Gurnell 2005), species abundance and diversity (Bain restricted the conclusions being drawn. In particular, et al., 1988; Bunn & Arthington 2002; Poff & the authors highlighted a lack of integrative Zimmerman 2010) and the behaviour and physiology approaches in fisheries management research (but of aquatic organisms (Dewson et al., 2007; Murchie see Patterson et al., 2016). Connecting research from et al., 2008; Pavlov et al., 2008). As a consequence, different natural science disciplines (for example, flow modification has been identified as a major threat linking behavioural responses that are mediated by to freshwater biodiversity (Dudgeon et al., 2006; complex flow dynamics to physiology or molecular Arthington et al., 2010; Reid et al., 2019) and is likely biology) would allow researchers to not only observe a significant contributor to the accelerated global trends but also identify the mechanisms driving the extinction rates of freshwater fauna over the past trends. Such an approach was encouraged over century (Ricciardi & Rasmussen, 1999; Strayer & 60 years ago, when Brett (1957) asserted that the Dudgeon, 2010). challenges dams pose to fish migrations could only be addressed through integrated research. Here, we review a large-scale, multi-year study that aimed to assess the effects of dam operations on R. Ledoux Pacific salmon (Oncorhynchus spp.) in the Seton St’a´t’imc Eco-Resources Ltd., Lillooet, BC V0K 1V0, Canada River—a tributary of Canada’s Fraser River—and to identify and evaluate operational strategies that would C. T. Middleton mitigate these effects. Previous research in this InStream Fisheries Research Inc, Squamish, river indicated potential negative effects of the dam BC V8B 0E8, Canada on the return migration of adult salmon (Andrew & V. Minke-Martin Geen, 1958; Fretwell, 1989). Through the involve- Pacific Wild Alliance, Victoria, BC V8W 2K1, Canada ment of ecologists, physiologists, hydraulic engineers, natural resource managers and fisheries practitioners W. Zhang Á D. Z. Zhu Department of Civil and Environmental Engineering, from academia, industry, government and First University of Alberta, Edmonton, AB T6G 1H9, Canada Nations, we examined the molecular, behavioural, 123 Hydrobiologia physiological, and population-level responses of Reservoir (of the adjacent Bridge River watershed) migrating adult sockeye salmon (Oncorhynchus and the 18-m tall Seton Dam was built to divert water nerka, Walbaum, 1792) to dam operations. Our exiting Seton Lake to a power canal, which leads to a methods included laboratory analyses, controlled generating station on the bank of the Fraser River. behavioural tests and large-scale management exper- After travelling through the Seton River, returning iments involving the manipulation of dam flow salmon must pass a vertical slot fishway at Seton Dam releases. We applied innovative technologies to these to enter Seton Lake and continue migrating to procedures and in some instances our applications spawning grounds at Gates Creek. were novel to the field of fisheries science. Our In addition to the challenge of dam passage, adult research builds on Brett’s (1957) assertion and salmon migrating through this system encounter demonstrates that integrating research approaches confusing directional cues as a consequence of from several disciplinary perspectives can lead to hydroelectric development (Andrew & Geen, 1958). management actions that are informed by rigorous Water released through the generating station, which science. In addition, our work underscores a potential is impassable to fish, enters the mainstem Fraser River benefit of research in regulated rivers: that the ease in 1 km downstream of the Seton-Fraser confluence which wild fish may be captured from (and studied in) (Fig. 2). Pacific salmon are guided to spawning fishways, in conjunction with the ability to directly grounds primarily by the odour of their natal streams manipulate flow, enables researchers to address fun- and lakes (Hasler & Scholz, 1983; Bett & Hinch, damental scientific questions. We review our approach 2016), and these attractive odours are present in the and findings and lay out the key lessons learned about water passing through the generating station. Salmon integrative