Size-selective harvesting associated with commercial and recreational fishing practices has been shown to alter life history traits through a phenomenon known as fishing-induced evolution. This phenomenon may be a result of selection pathways targeting life-history traits directly or indirectly through correlations with behavioral traits. Here, we report on the relationship between individual differences in behavior and capture technique (beach seining versus angling) in wild-caught juvenile bluegill sunfish ( Lepomis macrochirus ). Both fish caught by using a seine net (seined) and fish caught by using a lure (angled) were individually tested under standardized laboratory conditions for their boldness, water-column use, and general activity. Observed inter-individual differences in boldness were strongly correlated with method of capture in the wild. Fish caught by angling were more timid and had fewer ectoparasites than fish caught using a seine net. However, this relationship did not carry over to an experiment in a large outdoor pool with seine-caught, individually tagged wild fish, where bolder individuals were more likely to be angled in open water away from refuges than more timid individuals, based on their previously assessed boldness scores. Our study is both novel and important, as it describes the relationship between capture technique and boldness in a natural population and underscores the potential risk of sampling biases associated with method of animal capture for behavioral, population, and conservation biologists.

Spawning migrations of sturgeon have been affected by the construction of dams, which create barriers to migration and have contributed to the imperilment of sturgeon. Although devices have been installed to facilitate the upstream passage of fish at barriers, they have been generally unsuccessful and not designed for sturgeon. We examined fine-scale movements of adult lake sturgeon Acipenser fulvescens during passage through a vertical slot fishway located on the Richelieu River in Quebec, Canada, to determine passage success, passage duration and inter-individual differences in fishway use. Migratory lake sturgeon (n = 107, range 939 to 1625 mm total length [TL]) were captured immediately downstream of the fishway, tagged with passive integrated transponder (PIT) tags and released into the fishway entrance basin over a period of 2 wk (water temperature 11-20°C). An array of 16 PIT antennas acted as gates to enable quantification of movements within the fishway. Volitional entry into the fishway occurred for most individuals (82.2%), 32 individuals successfully ascended the entire fishway, and overall passage efficiency was 36.4%. Sturgeon exhibited an ability to traverse the fishway quickly (minimum duration of 1.2 h upon entry into the fishway); however, the duration of successful passage events was variable (6.2-75.4 h following release). Neither passage duration nor maximum distance of ascent was correlated with TL or water temperature. Passage behaviour was variable, in some cases resulting in cumulative upstream movements 3 times in excess of fishway length. Passage durations through the 2 turning basins were disproportionately longer compared with other basins; however, the activity of individuals within these and other locations remains unknown and represents an important knowledge gap. Collectively, data from this study contribute to understanding how fishways can be used to facilitate the upstream passage of imperilled sturgeon at dams. KEY WORDS: Acipenseridae • Sturgeon • Fishway • Fish passage • Migration • PIT Resale or republication not permitted without written consent of the publisher Contribution to the Theme Section 'Endangered river fish: threats and conservation options'

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Our understanding of biological criteria to inform fish passage design is limited, partially due to the lack of understanding of biological motivators, cues, and constraints, as well as a lack of biological performance evaluations of structures once they are built. The Vianney-Legendre vertical slot fishway on the Richelieu River, Quebec, Canada, passes large numbers of migrating redhorse (Moxostoma spp.) upriver to spawning grounds each year. We evaluated the physiological capacity and relative swimming ability of three redhorse species (Moxostoma anisurum, Moxostoma carinatum, Moxostoma macrolepidotum; silver, river, and shorthead redhorse, respectively) to determine how these biotic factors relate to variation in fishway passage success and duration. Shorthead redhorse had higher maximum metabolic rates and were faster swimmers than silver and river redhorse at their species-specific peak migration temperatures. Blood lactate and glucose concentrations recovered more quickly for river redhorse than for silver and shorthead redhorse, and river redhorse placed second in terms of metabolic recovery and swim speed. Interestingly, fish sampled from the top of the fishway had nearly identical lactate, glucose, and pH values compared to control fish. Using passive integrated transponders in 2010 and 2012, we observed that passage success and duration were highly variable among redhorse species and were not consistent among years, suggesting that other factors such as water temperature and river flows may modulate passage success. Clearly, additional research is needed to understand how organismal performance, environmental conditions, and other factors (including abundance of conspecifics and other comigrants) interact with fishway features to dictate which fish will be successful and to inform research of future fishways. Our research suggests that there may be an opportunity for a rapid assessment approach where fish chased to exhaustion to determine maximal values of physiological disturbance are compared to fish sampled from the top of the fishway, which could reveal which species (or sizes of fish) are approaching or exceeding their physiological capacity during passage.

Barriers resulting from anthropogenic activities (e.g., hydropower development, irrigation, flood control, low flow augmentation) can prevent the upstream migration of fish, reducing the connectivity of river systems. As a result, great efforts have been devoted to the design and installation of engineered fishways to enable the movement of fishes across barriers. However, the literature is generally devoid of scientific papers dealing with fishway design and effectiveness, making it difficult for those developing such facilities to determine which fishway designs are most appropriate for a given system and target species. One approach for providing information to support future fishway development is through the creation of databases that contain detailed accounts of existing facilities. Described here is the development of an engineered fishway database in Canada (called CanFishPass) intended to serve as a repository for information that has previously been difficult to find. The database includes detailed geo-referenced information such as engineering details, hydraulic characteristics, and biological effectiveness of one general class of fish passage facility (i.e., engineered fishways), as well as photographs and design drawings where available. The database is searchable by species, fishway type, and ecozone, and includes a reference section comprised of both peer-reviewed and ''grey'' literature. It is anticipated that the database will serve as an important resource for future fishway development projects enabling quantitative analyses, while also serving as the first inventory of engineered fishways in Canada. Although our efforts to date have been focused on Canada, the expansion to a global inventory of fishways would enable opportunities to learn directly from facility operations in other regions.

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