Defense Date

2020

Document Type

Thesis

Degree Name

Master of Science

Department

Environmental Studies

First Advisor

Paul Bukaveckas

Second Advisor

Rachel Mair

Third Advisor

Joseph Wood

Fourth Advisor

James Vonesh

Abstract

Abstract

The main objective of this study was to determine whether introduced freshwater mussels (Alewife floater, Utterbackiana implicata) can survive and grow in urban streams in the James River watershed. A secondary objective was to assess differences in U. implicata survival and growth of in the context of differing water quality and food resource conditions among three urban sites and three rural sites. Results from this study show large differences in growth and survivorship of mussels across sites. Higher survivorship was observed among mussels stocked into rural streams (35% and 44%) in comparison to urban streams (3%, 6% and 14%). High mortality in urban streams was largely due to washout and burial of mussels. These findings suggest that the “flashy” hydrology typically associated with urban streams is a significant impediment to successful introduction at these sites. High growth rates were observed in one of the rural streams (Herring Creek: 57 mg/d), whereas growth rates were less than 15 mg/d at all other sites. Food resource metrics showed statistically significant differences among sites with higher values of TSS, particle density, organic matter content and chlorophyll-a content at rural sites relative to urban sites. These findings suggest that rural sites had more favorable food resources than rural streams, though we did not find that food metrics were a significant predictor of variation in growth rates among sites. We did not find that water quality metrics (temperature, dissolved oxygen) were a significant predictor of variation in mussel growth rates. Overall, these findings suggest that hydrologic conditions in urban streams pose a significant challenge to the successful reintroduction on native mussels.

Rights

© The Author

Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission

8-7-2020

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