Graduate Students
There are opportunities to participate in research projects related to the ecology of tidal freshwater rivers and other topics. If you have an interest, please contact me and visit the graduate program web page for the VCU Center for Environmental Studies or the graduate program web page for the Integrated Life Sciences PhD Program.
Recent Students and their Projects:
Samantha Rogers (PhD 2023 Integrated Life Sciences) – Samantha’s project focused on aquatic insect emergence from the tidal freshwater segment of the James Estuary. Emergent aquatic insects (dragonflies, midges, etc.) are an important food resource for riparian consumers including birds, bats and spiders. Prior studies have documented large-scale emergence of aquatic insects, such as mayflies from the Mississippi River, but we knew of no prior studies on tidal rivers. Samantha deployed emergence traps in multiple locations of the James and found high rates of emergence, exceeding those typically reported for lakes and streams. Because these insects feed on algae during their aquatic stage, they were found to have higher lipid content in comparison to terrestrial insects. Related work carried out by Samantha and her co-advisor (Lesley Bulluck) showed that warbler nestlings fed a higher proportion of aquatic prey outperformed nestlings provisioned with terrestrial prey. By combining this work with Lesley’s long-term study of Prothonotary warblers, we hope to learn more about aquatic food subsidies to riparian food webs.
Rachel Henderson (MS 2021 Environmental Studies) – Rachel’s project focused on the factors influencing water clarity in upper estuarine segments of the James and York. We found that inorganic suspended particulate matter was the primary agent causing poor water clarity in these estuaries. For the sub-estuaries of the York (Pamunkey and Mattaponi), dissolved color originating from wetland sources was also an important factor. Long-term data suggest that water clarity is improving but has not yet reached the point where the growth of submerged aquatic vegetation would dominate over phytoplankton. A paper based on our research is currently in review at Estuaries & Coasts.
Jack Ryan (MS 2020 Environmental Studies) – Jack’s project investigates the feasibility of restoring endangered freshwater mussels to urban streams. Mussels have the potential to provide important ecosystem services by filtering water, removing sediment and other particulates, and promoting in-stream denitrification. Recent advances in mussel propagation allow the possibility of restoring them to habitats where they likely once occurred, but have been extirpated due to poor water quality conditions. Jack placed mussels in cages in three urban streams, two non-urban streams to assess their growth, survivorship and physiological status. This project is being done in collaboration with Rachel Mair at the Harrison Lake National Fish Hatchery .
Joe Famularo (MS 2019 Biology) – Joe’s project focused on nutrient limitation of urban and non-urban streams in central Virginia. Urban streams exhibit higher nitrogen concentrations in comparison to nearby forested streams and therefore we expected that they would respond more strongly to additions of phosphorus. We were surprised to find that there were no consistent differences in nitrogen vs. phosphorus limitation among these streams. We did find that urban streams provide a high level of biogeochemical functioning in removing N and P and preventing their downstream transport.
Rikki Lucas (MS 2019 Biology) – Rikki’s project focused on the hydrologic and geomorphological properties of urban streams. This work was conducted as part of our urban stream monitoring project for the City of Richmond. Although the Urban Stream Syndrome predicts poor hydrologic functioning of these streams, we found that urban streams were quite variable in their capacity to store water for short periods of time. Results from this study will be useful for interpreting differences in water quality among these streams, and may help to inform stream restoration efforts. We are grateful to our colleagues at the USGS Richmond office for their technical advice on this project.