Blog Education OSCAR

Katie Russels Wins Student Excellence Award

Undergraduate Katie Russell conducted research on river herring with Dr. de Mutsert. She presented at the GMU Spring 2020 Symposium, where she was also award the OSCAR Student Excellence Award.


Ben Rhoades Wins Student Excellence Award

Advised by Dr. Amy Fowler and Dr. Dann Sklarew, ESP undergraduate Ben Rhoades won the 2020 OSCAR Student Excellence Award for his research on microplastics in the Potomac.


Graduate Student Awarded Boren Fellowship

Dr. Kim de Mutsert’s Graduate student, Sara Marriott, has been awarded a Boren fellowship, which will allow her to include fieldwork in the Philippines as part of her dissertation research.

From Sara:

“Boren Awards are made up of three parts, Language, Culture and Service. Through this fellowship, I will have the opportunity to travel to the Philippines for six months to study Tagalog and conduct research. My Ph.D. research is on social-ecological systems in small-scale fishery management in the Philippines, in which part of my research will be interviewing fishers and community members to better understand how community-based management practices work. Small-scale fisheries make up a large portion of unreported or under-regulated fishing and researching ways to make this sector more sustainable is important for both ecosystems and livelihoods of fishers. Finally, upon graduation, Boren Fellows are required to spend a year of service in the federal government, bringing their experiences and knowledge gained from the fellowship into US policy. This fellowship excites me because I hold stakeholder engagement as a core tenant. It is easy to just look at the numbers of fish biomass to determine impact, but in doing that I believe that you miss a large portion of the story of how and why different management/governance structures are or are not working. Having the opportunity to live in my study area working directly with fishers for six months is a dream come true in addition to enhancing my research outcomes.”

Congratulations Sara, we can’t wait to see where this takes you!

Blog In the News

35-Year Study of Gunston Cove Published

For 35 years, Dr. Chris Jones has sampled Gunston Cove, a tributary to the Potomac. He has recently published a long-term study, tracking the ecosystem’s recovery. The results of his research indicate that submerged aquatic vegetation (SAV) have returned (previously, there was none) as a result of increased water clarity. SAV provide important habitats for fish and invertebrates in the Potomac River. While there is still a long-way to go, this study demonstrates that it is possible to recover ecosystems that have been damaged by pollution. You can read Recovery of a Tidal Freshwater Embayment from Eutrophication: a Multidecadal Study here.


Effective management of eutrophication in tidal ecosystems requires a thorough understanding of the dynamics of their responses to decreases in nutrient loading. We analyze a 34-year dataset on a shallow embayment of the tidal freshwater Potomac River, Gunston Cove, for long-term responses of ambient nutrient levels, light transparency measures, phytoplankton biomass, and coverage of submersed aquatic vegetation (SAV) to decreased nutrient loading. Point source loading of phosphorus, the nutrient most limiting primary production in this system, was greatly curtailed coincident with the study onset (1983/84) exhibiting a sharp decrease of 95% from peak loading levels. However, water column total phosphorus decreased much more slowly and gradually. Phytoplankton chlorophyll a did not show a distinctive decrease until 2000 and SAV responded strongly beginning in 2004. The habitat suitability model for SAV developed by Chesapeake Bay researchers was able to explain the recovery of SAV coverage based on data on light transparency and basin morphometry collected in this study. The study results were consistent with the alternative stable state theory with a sharp transition from a phytoplankton-dominated “turbid water” state to an SAV-dominated “clear water” state in a 2-year period from 2003 to 2005. The system eventually responded to nutrient load reductions, but the nonlinear and incomplete nature of this recovery and the two-decade delay illustrate the complexities of managing these systems.

Blog Education

What Kind of Research Can GMU Students Do?

What kind of research opportunities are open to George Mason undergraduates? Hear from Keith, a student encouraged to apply for a Research Experience for Undergraduates (REU) by Dr. Cindy Smith. Hear him talk about what it was like to research fisheries with the Gulf of Maine Institute (

Blog In the News

Student Accomplishments

Congratulations to the students of Dr. Kim De Mutsert on the following accolades:

Students and Dr. De Mutsert at the ecopath conference
L-R: Casey Pehrson, Dr. Kristy Lewis (University of Central Florida), Dr. Kim de Mutsert, Sara Marriott, and Sammie Alexander.

Sara Marriott was awarded a prestigious SESYNC Graduate Pursuit Fellowship, which is an an 18-month fellowship in which she is part of an interdisciplinary team that will be researching “A socio-environmental approach to improve offshore aquaculture and policy: Gulf of Mexico case study.” It supports travel and meetings to conduct research, provides access to SESYNC workshops and resources, as well as a stipend/honorarium of $2,000.

Sammie Alexander received a $5,000 program development award from Virginia Sea Grant for her project: “Assessment of fish passage use and success in facilitating movement of regionally vulnerable and invasive fish species in northern Virginia portion of the Potomac River.” This is the second award she has received from VA Sea Grant.

Kate Russel with her winning poster

Casey Pehrson was awarded the Robert D. Ross Graduate Scholarship in fisheries and related aquatic sciences from the Virginia Chapter of the American Fisheries Society. She received the second place award, which comes with a $250 check.

Katie Russell won the best undergraduate poster award at the Virginia Chapter of the Wildlife Society Conference that was held this week.


New Tools, New Techniques, New Technology

Dhanush and Tom processing samples in the lab

I am very excited to share what our lab has been working on for the 2019 Summer Impact Research Project: Microbial Communities as Indicators of Ecological Health. Dhanush Banka (a student from Thomas Jefferson High School for Science and Technology) and I have been working in Dr. Salerno’s lab at the Potomac Science Center, George Mason’s research center on the Occoquan River. Our environmental samples have been collected by Dr. van Aken’s lab, where fellow OSCAR student Nick Mills is working on the sediment samples. My focus is on the water samples taken from Cameron Run and Hunting Creek in Alexandria, VA as part of the environmental monitoring project that GMU does in association with Alexandria Renew Enterprises, the local wastewater processor for that area.

This is the first year that water samples are being surveyed to determine the microbial population. We have learned how to perform DNA extractions from the samples, how to quantify our results using two different methods, and also how to amplify the DNA in preparation for submitting the samples for DNA sequencing. We’ve been waiting patiently for the sequencing data, which will allow us to identify not only the types of bacteria present, but also the relative abundances to be able to get an idea of the composition of the microbial community. We’re correlating those results with rainfall, water flow, river height, and temperature data to build a profile and possibly model how changes in the environment will affect the microbial community. Since Cameron Run parallels the Capital Beltway and Hunting Creek adjoins Alexandria, the water samples are from an urban environment, and we expect the composition of the microbial community to reflect that.

Preparing for a DNA Extraction in the lab

As with most things regarding our environment, we don’t know where we’re going if we don’t know where we’ve been. Without some initial information, surveys, or records, we don’t know what affect our changing climate or other anthropogenic activities are making in our own environment. The unseen microbial community far outnumbers all of the life that we can see, and because it grows so much more quickly than other visible organisms the microbial community is the ‘pulse’ of the environment. Our ability to identify microbial families through the use of environmental DNA is a breakthrough, a new tool that we’re only beginning to learn how to use. We now have the genetic tools available to discover far more detail about the world around us than we have ever had in our history. As an older, non-traditional student, I’m excited to be part of this research, even as an undergraduate student. These new tools, this new technology, and these new techniques are what inspired me to pursue a degree in biology. That’s what I wanted to learn and that’s why I’m at George Mason University where I am part of a team using these tools to conduct real field research in my own community.


2019 OSCAR Student Summer Impact Project

By: Jeremy Williams

This a male Banded Killifish (Fundulus diaphanous). This picture was taken during my first day sampling in Gunston Cove.

Life in the aquatic environment has always had my interest since I was young. It’s just something about life under water that fascinates me. My OSCAR research project this summer has been a phenomenal experience so far. Learning about fish communities and assemblages has shown me a different perspective of life. I never really knew how dynamic and complex a fish’s life could be until I came here. Now, I have developed appreciation, care, and respect for all fishes. In addition to studying about fishes, I also learned how to identify fish on the adult, juvenile, and larval level. I believe that identifying fish can be rewarding because it can get difficult trying find the intricate details to identify each fish at different stages of their lives. Also, being able to go out on the boat every week and seeing the natural scenery of both sample sites is something that the “Average Joe” doesn’t get to see every day.

Our first week at PSC, Ben and I dissected a Remora AKA “Shark Sucker” in Dr. de Mutsert’s fish lab.

Being around other people that are passionate about science and love it just as I do makes me feel right at home. Coming to work and being able to sit in the lab to doing science every day is feeling that I cannot explain. I love every second of arriving to the Potomac Science Center and looking out the window to see that awesome view of the Potomac River. Furthermore, the people in the building are all friendly and are willing to help anyway they can. This might seem small but having key card access to your lab is so awesome! It makes you feel like you are entering in a TOP SECRET room, but it’s just your lab. All this fun and excitement comes with hard work as well. I have taken pride in my research and study and cannot wait to present my project findings at the poster presentation to show what I’ve been working on this entire summer. If I could give advice to future student researchers, it would be to apply to not only just OSCAR internships but to any internship. I guarantee that it will be an experience you will never forget.

In the midst of all this happiness and joy, the entire room smells like fishes!

Undergraduate DMV Microplastics Study

By: Ben Rhoades

I can see plastic everywhere now– and not just the water bottles on the side of the trail or the plastic bags in branches, but the tab you pull off of a disposable squirt bottle and the tiny corner torn off of a granola bar. The most visually impactful part of this summer has been picking through fully processed microplastic samples as we work to quantify just how much plastic pollution is present in the Potomac River and the streams that feed into it.

Microplastics are pieces of plastic, either fragmented or intentionally produced, that are between 5mm and 0.3mm in diameter and are the center of increased media and academic attention. My lab partner and I have spent this summer studying these small bits of plastic in local waterways hoping to build off of the work of Mason PhD student Doreen Peters and the published work of Yonkos et al. (2015) who reported on microplastic in the Chesapeake Bay. Despite the work of both scientists, no data has been published on the presence, abundance, or concentration of microplastics in the Potomac River. This is where Han and I enter the scene.

Most microplastics research focuses on those plastics found floating at the surface of aquatic environments using a buoyant net named after its look-alike a Manta Ray. Using one of these Manta nets housed at the Potomac Science center, we’ve sampled Hunting Creek in Alexandria, VA; Gunston Cove in Woodbridge, VA; and the Anacostia River in Washington, DC. However, we also have used a novel stream sampling approach that uses a round-mouthed net anchored to either side of a stream and left for an hour to passively collect microplastics. Our lab’s principle investigator, Dr. Foster, and I sampled Accotink Creek, Cameron Run, and the Northeast Branch of the Anacostia River using our self-engineered technique. Finally, in an attempt to see if there is movement of microplastics into the food web, we extracted and analyzed the digestive tracts of four catfish.

Manta net collecting plastic near National Harbor, DC

Through this project, I hope to have some idea of an ideal sampling method that is representative of the who ecosystem a researcher is investigating, whether it is surface water sampling, sediment sampling, or fish-gut analysis. Also, am testing whether these sites differ in each of those sampling methods, and if so, what contributes to those differences. We have just finished our sample processing, which involved hours of drying samples, chemical digestion, picking at and counting plastics under a microscope, and finally I will have a chance to crunch our numbers and test these hypotheses.

Looking back, I thought I would know what to expect with this summer: sampling, processing, analysis, etc, however, I’ve learned that each research experience is unique and rewarding in its own way. First of all, becoming familiar a with a completely new and ever-growing field of literature has been an exciting challenge. Also, working with old and new faces in the lab and in the field, I have learned that all PIs and lab partners are different and that relationships and expectations are always… plastic.


My Research, In a Snail Shell

By: Grace Loonam

Photo taken at Hopyard Landing, a site on the Rappahannock River. This sample was taken in twenty minutes, with a total of 272 invasive and 90 native snails being collected during this time.

This summer, I have been working on a Summer Team Impact Project at the Potomac Science Center in Woodbridge, Virginia. I have been studying an invasive species of snails―termed mystery snails―and by collecting samples of these invaders and their native counterparts, I aim to learn more about the mystery snails as a whole, as well as how their parasitology differs from that of the snails that are native to this region. This research is important because both invasive species and parasites threaten the biodiversity of an ecosystem, and biodiversity is important for ensuring that the ecosystem can withstand stressors and catastrophic events that would otherwise destabilize the ecological balance. The overarching project is focused on aquatic communities as bioindicators of change, and although the other members of my team specifically focus on the Potomac River for their research, I also sample from other rivers in the Northern Virginia area.

It’s been very exciting to take part in research that allows me to experience lab-based research as well as fieldwork. The amount that I’ve learned in both settings is unreal (pro-tip: it’s a lot easier to find and collect snails at low tide), and the following picture was taken of me while collecting snails from a site on the Rappahannock for the second time, as we could hardly find anything the first time around.