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The effectiveness of catch and release as a conservation practice assumes minimal impacts to released fish. In most cases, angling‐related stressors can be mitigated via changes to angler behavior that reduce fight duration, handling, and air exposure. In some cases, stressors may significantly impact the ability of fish to engage in normal swimming behavior upon release. In these scenarios, it may be beneficial for anglers to assist recovery or retain fish until they are adequately recovered. We investigated the effectiveness of two assisted‐recovery devices at facilitating behavioral recovery in angled Rainbow Trout Oncorhynchus mykiss: (1) retention in a flow box, or (2) retention in a water‐filled cooler. Additionally, we compared the effects of assisted recovery in surface water (24–27°C) or cool water pumped from the hypolimnion (17–19°C). From July to mid‐September 2020, 169 fish were angled from five stocked lakes at Kenauk Nature (Montebello, Quebec). Fish were air exposed for 30 s, for 15 s, or not at all (0 s) and were held in a flow box or a water‐filled cooler for 3 min, while fish in a control group were immediately released. Triaxial acceleration and temperature biologgers were temporarily fixed around the trunk of the fish with Velcro to observe postrelease swimming behavior for 10 min. Rainbow Trout that were held in assisted‐recovery devices regained equilibrium significantly more quickly than those that were immediately released, and fish that were held in 17–19°C water regained equilibrium the most rapidly. In fish that were air exposed for 30 s, individuals that were held in recovery devices exhibited greater swimming activity compared to those that were immediately released. Our study demonstrates that for Rainbow Trout, assisted‐recovery devices can reduce equilibrium impairment, especially when water in the recovery devices is significantly cooler than the relatively warm surface water temperature. Global water temperatures are expected to rise as a result of anthropogenic climate change, and best practices for angling should be adapted to reflect increased thermal stressors for many game fish species. Ensuring that fish are vigorous upon release is imperative for reducing postrelease mortality caused by predation or thermal stress. [ABSTRACT FROM AUTHOR]

Freshwater biodiversity is in a state of crisis. The recent development of a global emergency recovery plan to "bend the curve" for freshwater biodiversity lacks the necessary details for implementation in a regional context. Using Canada as an example, we describe a toolbox intended to equip decision-makers and practitioners with evidence-based tools for addressing threats to freshwater biodiversity. The toolbox includes two rubric-based scoring tools to inform users about the level of the reliability (e.g., transparent methods, critical appraisal) and relevancy to Canadian freshwater systems (e.g., habitat, species) of an evidence synthesis. Those scoring tools were applied to 259 evidence syntheses, also included in the toolbox, across fifty freshwater management actions. Habitat Creation, Invasive Species Removal, and Revegetation were found to have reliable evidence syntheses but there remain several actions for which the syntheses are not robust and where the evidence base is unreliable. We suggest the need for more rigorously conducted empirical tests of freshwater management actions, further evidence synthesis, and clearer conveyance of implications for decision-makers and practitioners. Decision-makers and practitioners should use the two scoring tools on syntheses outside this project and tailor them to their regions. Given the global interest in addressing the freshwater biodiversity crisis and the necessity to engage and empower decision-makers and practitioners on a regional basis, we anticipate this toolbox will serve as a model for regions beyond Canada. Future studies to understand if and how the toolbox is used will be needed to make refinements and ensure it benefits freshwater biodiversity. • Current management of freshwater ecosystems fails to address the global freshwater biodiversity crisis • Evidence syntheses and reviews are a valuable resource to decision-makers and practitioners for informing conservation actions • The toolbox consists of over 250 freshwater management evidence syntheses, scored based on the included appraisal tools • Syntheses demonstrate a poor systematic review conduct but show a strong potential for regional relevance and applicability [ABSTRACT FROM AUTHOR]