Studies examining selection and fitness differences between phenotypes are essential for our understanding of evolutionary processes. Although many studies have examined fitness effects of morphological and life-history traits, studies of selection on personality traits are much less common. This has been due, in part, to the fact that personality is not easily characterized into phenotypes. In addition, personality has historically been viewed as highly plastic and therefore less likely to be under the direct influence of selection. However, recent studies suggest that personality is often consistent over biologically meaningful time periods. If personality traits are consistent across development, they have the potential to affect fitness through impacts on survival at the juvenile stage and reproductive success at the adult stage. Thus, personality traits may have a range of effects on fitness, some of which could result in tradeoffs. Further, personality likely determines an individual's vulnerability to human capture and harvest in a variety of contexts, which means human actions could alter the effects of personality on fitness. For example, a fish's personality may affect its vulnerability to capture by recreational angling, which could alter the relationships between personality and survival and reproductive success. Moreover, if personality traits are heritable, angling could result in the evolution of personality traits in angled populations, which could have ecological consequences. Consequently, studies to explain how personality is generated and maintained by evolution are greatly needed. Here, I address the fitness consequences of multiple personality traits across life stages and their heritability in largemouth bass (Micropterus salmoides). Further, I address how angling could alter these fitness effects. To quantify personality and investigate its consistency, bass were observed in the laboratory under experimental behavioral contexts at age-1, age-3, age-4, and age-5. Bass behavior was observed in four contexts: 1) a novel environment, 2) a familiar and safe environment, 3) a social environment (mirror-test), and 4) an environment in which both food and a predator were present. To quantify the fitness effects across life stages of the personality traits uncovered in the experimental behavioral assays, experiments were conducted in outdoor ponds on juvenile survivorship and on adult reproductive success. Further, bass were subjected to one of three angling contexts: 1) a mesocosm context, 2) an outdoor pond context, and 3) an outdoor pond context with casts made directly onto bass nests. Lastly, personality was quantified in two generations of bass to assess personality heritability. The results showed that bass have context-specific personality traits that underlie the expression of behavior in each of the four contexts investigated and that the context-specific traits are sub-modules of a context-general trait, which was identified as boldness. The boldness trait, as well as some of the context-specific traits, were consistent across multiple years and developmental stages. Bolder juvenile bass had significantly lower survivorship than their conspecifics while adult bass that were larger and bolder had significantly higher reproductive success. Additionally, relationships were found between some of the context-specific traits and juvenile survival and reproductive success. Bolder bass were more vulnerable to angling in the mesocosm context and bolder nesting males were more vulnerable to nest angling. Additional relationships were found between some of the context-specific traits and angling vulnerability. Boldness was the only personality trait that was significantly heritable. The results of this dissertation demonstrate for the first time that personality traits that are consistent across development can affect fitness in multiple ways over the course of an individual's lifetime. In some environments, these fitness effects can result in tradeoffs that could maintain within population variation in personality traits. Further, the results indicate that the selective capture of fish by angling can alter the selective landscape acting on personality traits, which could have significant evolutionary and ecological consequences and could affect the quality of fisheries.
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