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Top predators are known to play an important role in the assembly of communities via two mechanisms: (1) by altering the colonization (or emigration) patterns of prey through behavioral habitat selection, and (2) by altering vital rates (e.g. mortality, birth) of prey after colonization. While both these mechanisms act to determine assembly, research has focused on either their combined overall effects (confounding them), or examined them singly. As a result, it remains unclear how these mechanisms act to sequentially shape community structure. In this study, we experimentally disentangle habitat selection and post‐colonization effects of predaceous fish to test their independent and combined influence on the assembly of insect and larval amphibian communities in experimental freshwater habitats. Specifically, we ask, ‘do the behavioral choices of colonists continue to structure aquatic communities even after post‐colonization processes have occurred?’ Like previous studies, we found that colonization was strongly reduced by the presence of fish cues. More importantly, these effects of fish on prey colonization behavior combined independently with post‐colonization processes to determine the overall effect of predators on community assembly. Although habitat selection and predation both reduced abundance and biomass of most taxa in the post‐colonization communities, these factors had qualitatively different effects on aspects of trophic structure. Habitat selection altered the ratio of secondary to primary consumer abundance and biomass, while post‐colonization predation drove strong trophic cascades not observed in response to habitat selection. Our results suggest that behavioral choices regarding habitat selection can have lasting and unique effects on the structure of aquatic communities.

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Social inequality is a trademark of Northwest Coast native societies, and the relationship between social prestige and resource control, particularly resource ownership, is an important research issue on the Northwest Coast. Faunal remains are one potential but as yet underutilized path for examining this relationship. My thesis work takes on this approach through the analysis of fish remains from the Cathlapotle archaeological site (45CL1). Cathlapotle is a large Chinookan village site located on the Lower Columbia River that was extensively excavated in the 1990s. Previous work has established prestige distinctions between houses and house compartments, making it possible to examine the relationship between prestige and the spatial distribution of fish remains. In this study, I examine whether having high prestige afforded its bearers greater access to preferred fish, utilizing comparisons of fish remains at two different levels of social organization, between and within households, to determine which social mechanisms could account for potential differences in access to fish resources. Differential access to these resources within the village could have occurred through household-level ownership of harvesting sites or control over the post-harvesting distribution of food by certain individuals. Previous work in this region on the relationship between faunal remains and prestige has relied heavily on ethnohistoric sources to determine the relative value of taxa. These sources do not provide adequate data to make detailed comparisons between all of the taxa encountered at archaeological sites, so in this study I utilize optimal foraging theory as an alternative means of determining which fish taxa were preferred. Optimal foraging theory provides a universal, quantitative analytical rule for ranking fish that I Thank you so much to Virginia Butler for being an exceptional advisor who pushed me to do my best work. This project would not have been possible without your guidance. I am greatly indebted to everyone whose previous work on Cathlapotle made this project possible. In particular, thank you to Ken Ames for your enthusiasm about my work and many rounds of helpful notes. Thank you to Shelby Anderson for stepping in at the last minute to join my thesis committee and for the insightful comments you provided. I received assistance with my analysis from several people: Virginia Butler completed a portion of the fish identification prior to my work on the project, Kathryn Mohlenhoff measured a portion of the salmon vertebrae, and Emma Bailey and Nathan Jereb helped sort fish remains from the bulk sample matrix. Finally, thank you to my fellow students whose company made the countless hours spent in lab staring at fish bones bearable and to my parents who have given me endless support.