Integration of fisheries ecology with the assessment of microplastic consumption in black bass in the upper Ohio River drainage

This thesis explores the dynamics of microplastic consumption of black bass (smallmouth, Micropterus salmoides, largemouth, M. dolomieu, and spotted bass, M. punctulatus) in the Monongahela and Kanawha River and explores dietary characteristics in the Ohio, Monongahela, and Kanawha River. The first chapter serves as an introduction and synthesis of microplastic consumption, fisheries ecology, and regional information. The second chapter quantifies microplastic consumption in the Monongahela River and explores spatial variation within and between species by pool and seasonal effects. The third chapter consists of exploratory Quasi Poisson modeling of total microplastics in the Point Marion pool, Monongahela River, WV using microplastic shape characteristics, fish population characteristics and dietary metrics. The fourth chapter quantifies microplastic consumption in the Kanawha River and explores annual variation. Comparisons are made between the Monongahela River and the Kanawha River to determine how consumption changes throughout the landscape. The final chapter assesses black bass diet in the Monongahela, Kanawha, and Ohio Rivers. Microplastic consumption has been noted in a wide array of ecosystems but remained unquantified and understudied in freshwater riverine environments and consumption has not been previously explored in the Upper Ohio River drainage. This study is the first to quantify microplastic consumption of black bass in the Monongahela and Kanawha Rivers. Quasi Poisson general linearized models and contrasts were used to determine significant variation within and between species in each river system as well as temporally and spatially. All individuals examined contained microplastic. In the Monongahela River the maximum count was 281 pieces, accumulations that are similar in scale to what has been noted in Great Lake fish. Across pools within species variation expressed few significant differences, but interspecies differences demonstrated a higher number of significant relationships potentially due to differences in behavior aspects (diet and habitat residency) and habitat within pools. Significant changes in seasonal consumption may be linked to changes in availability within the system or behavior and should be further explored. In the Kanawha River, black bass consumed microplastic in lower quantities. Between years intraspecies significant variation was minimal but interspecies variation displayed a higher number of significant relationships. The Monongahela River and Kanawha River displayed a high number of significantly different relationships in microplastic consumption in the three species demonstrating that patterns of consumption can vary within species between river systems. Exploratory modeling of microplastic consumption demonstrated the significance of population characteristics as well as dietary information to understanding consumption. Comparative dietary analysis of the three black bass species in the Ohio, Kanawha and Monongahela River determined that the three black bass species display diet characteristics of the system, potentially influenced by the high turbidity within that environment.