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.

In salmonid aquaculture, a variety of technologies have been deployed that attempt to limit a range of environmental impacts associated with net-pen culture. One such technology employs a floating, solid-walled enclosure as the primary culture environment, providing greater potential control over negative interactions with surroundings waters while limiting energy use required for water circulation, thermo-regulation and supplemental oxygen provision. Here, we utilize life cycle assessment to model contributions to a suite of global-scale resource depletion and environmental concerns (including global warming potential, acidification potential, marine eutrophication potential, cumulative energy use, and biotic resource use) of such a technology deployed commercially to rear Chinook salmon in coastal British Columbia, Canada. Results indicate that at full grow-out, feed provisioning and on-site energy use dominate contributions across four of five impact categories assessed. For example, per tonne of salmon harvested, feed contributed approximately 72% to global warming potential, 72% to acidification potential, and accounted for 100% of biotic resource use. However, for both feed and on-site energy use, impacts are heavily influenced by specific sources of inputs; therefore efforts to improve the environmental performance of this technology should focus on reducing these in favor of less impactful alternatives.

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